A Step Closer for Clean Fuel: New Catalyst (Carbon-Based Nanocomposites) for Hydrogen Production


Flask in scientist handCarbon-based nanocomposite with embedded metal ions yields impressive performance as catalyst for electrolysis of water to generate hydrogen

A nanostructured composite material developed at UC Santa Cruz has shown impressive performance as a catalyst for the electrochemical splitting of water to produce hydrogen. An efficient, low-cost catalyst is essential for realizing the promise of hydrogen as a clean, environmentally friendly fuel.

Researchers led by Shaowei Chen, professor of chemistry and biochemistry at UC Santa Cruz, have been investigating the use of carbon-based nanostructured materials as catalysts for the reaction that generates hydrogen from water. In one recent study, they obtained good results by incorporating ruthenium ions into a sheet-like nanostructure composed of carbon nitride. Performance was further improved by combining the ruthenium-doped carbon nitride with graphene, a sheet-like form of carbon, to form a layered composite.

“The bonding chemistry of ruthenium with nitrogen in these nanostructured materials plays a key role in the high catalytic performance,” Chen said. “We also showed that the stability of the catalyst is very good.”

The new findings were published in ChemSusChem, a top journal covering sustainable chemistry and energy materials, and the paper is featured on the cover of the January 10 issue. First author Yi Peng, a graduate student in Chen’s lab, led the study and designed the cover image.

Hydrogen has long been attractive as a clean and renewable fuel. A hydrogen fuel cell powering an electric vehicle, for example, emits only water vapor. Currently, however, hydrogen production still depends heavily on fossil fuels (mostly using steam to extract it from natural gas). Finding a low-cost, efficient way to extract hydrogen from water through electrolysis would be a major breakthrough. Electricity from renewable sources such as solar and wind power, which can be intermittent and unreliable, could then be easily stored and distributed as hydrogen fuel.Figs-2A-and-2B

Polymer electrolyte membrane (PEM) water electrolysis cell Figure 2B (right): Schematic of an electrochemical energy producer. PEM hydrogen /oxygen fuel …

Currently, the most efficient catalysts for the electrochemical reaction that generates hydrogen from water are based on platinum, which is scarce and expensive. Carbon-based materials have shown promise, but their performance has not come close to that of platinum-based catalysts.

In the new composite material developed by Chen’s lab, the ruthenium ions embedded in the carbon nitride nanosheets change the distribution of electrons in the matrix, creating more active sites for the binding of protons to generate hydrogen. Adding graphene to the structure further enhances the redistribution of electrons.

water-splitting 2

 

“The graphene forms a sandwich structure with the carbon nitride nanosheets and results in further redistribution of electrons. This gives us greater proton reduction efficiencies,” Chen said.

The electrocatalytic performance of the composite was comparable to that of commercial platinum catalysts, the authors reported. Chen noted, however, that researchers still have a long way to go to achieve cheap and efficient hydrogen production.

In addition to Peng and Chen, coauthors of the study include Wanzhang Pan and Jia-En Liu at UC Santa Cruz and Nan Wang at South China University of Technology. This work was supported by the National Science Foundation and the NASA-funded Merced Nanomaterials Center for Energy and Sensing.

Story Source:

Materials provided by University of California – Santa Cruz. Original written by Tim Stephens. Note: Content may be edited for style and length.


Journal Reference:

  1. Yi Peng, Wanzhang Pan, Nan Wang, Jia-En Lu, Shaowei Chen. Ruthenium Ion-Complexed Graphitic Carbon Nitride Nanosheets Supported on Reduced Graphene Oxide as High-Performance Catalysts for Electrochemical Hydrogen EvolutionChemSusChem, 2018; 11 (1): 130 DOI: 10.1002/cssc.201701880
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Rice University Study Boosts Hope for Cheaper Fuel Cells


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Rice researchers show how to optimize nanomaterials for fuel-cell cathodes

Nitrogen-doped carbon nanotubes or modified graphene nanoribbons may be suitable replacements for platinum for fast oxygen reduction, the key reaction in fuel cells that transform chemical energy into electricity, according to Rice University researchers.

The findings are from computer simulations by Rice scientists who set out to see how carbon nanomaterials can be improved for fuel-cell cathodes. Their study reveals the atom-level mechanisms by which doped nanomaterials catalyze oxygen reduction reactions (ORR).

The research appears in the Royal Society of Chemistry journal Nanoscale.

Theoretical physicist Boris Yakobson and his Rice colleagues are among many looking for a way to speed up ORR for fuel cells, which were discovered in the 19th century but not widely used until the latter part of the 20th. They have since powered transportation modes ranging from cars and buses to spacecraft.

The Rice researchers, including lead author and former postdoctoral associate Xiaolong Zou and graduate student Luqing Wang, used computer simulations to discover why graphene nanoribbons and carbon nanotubes modified with nitrogen and/or boron, long studied as a substitute for expensive platinum, are so sluggish and how they can be improved.

Doping, or chemically modifying, conductive nanotubes or nanoribbons changes their chemical bonding characteristics. They can then be used as cathodes in proton-exchange membrane fuel cells. In a simple fuel cell, anodes draw in hydrogen fuel and separate it into protons and electrons. While the negative electrons flow out as usable current, the positive protons are drawn to the cathode, where they recombine with returning electrons and oxygen to produce water.

The models showed that thinner carbon nanotubes with a relatively high concentration of nitrogen would perform best, as oxygen atoms readily bond to the carbon atom nearest the nitrogen. Nanotubes have an advantage over nanoribbons because of their curvature, which distorts chemical bonds around their circumference and leads to easier binding, the researchers found.

Rice logo_rice3The tricky bit is making a catalyst that is neither too strong nor too weak as it bonds with oxygen. The curve of the nanotube provides a way to tune the nanotubes’ binding energy, according to the researchers, who determined that “ultrathin” nanotubes with a radius between 7 and 10 angstroms would be ideal. (An angstrom is one ten-billionth of a meter; for comparison, a typical atom is about 1 angstrom in diameter.)

They also showed co-doping graphene nanoribbons with nitrogen and boron enhances the oxygen-absorbing abilities of ribbons with zigzag edges. In this case, oxygen finds a double-bonding opportunity. First, they attach directly to positively charged boron-doped sites. Second, they’re drawn by carbon atoms with high spin charge, which interacts with the oxygen atoms’ spin-polarized electron orbitals. While the spin effect enhances adsorption, the binding energy remains weak, also achieving a balance that allows for good catalytic performance.

The researchers showed the same catalytic principles held true, but to lesser effect, for nanoribbons with armchair edges.

“While doped nanotubes show good promise, the best performance can probably be achieved at the nanoribbon zigzag edges where nitrogen substitution can expose the so-called pyridinic nitrogen, which has known catalytic activity,” Yakobson said.

“If arranged in a foam-like configuration, such material can approach the efficiency of platinum,” Wang said. “If price is a consideration, it would certainly be competitive.”

Zou is now an assistant professor at Tsinghua-Berkeley Shenzhen Institute in Shenzhen City, China. Yakobson is the Karl F. Hasselmann Professor of Materials Science and NanoEngineering and a professor of chemistry.

The research was supported by the Robert Welch Foundation, the Army Research Office, the Development and Reform Commission of Shenzhen Municipality, the Youth 1000-Talent Program of China and Tsinghua-Berkeley Shenzhen Institute.

Nikola Motors – Daimler – Toyota Challenge Tesla’s Metrics for the ‘Long-Haul’ – Will the Best Zero-Emissions Semi (Trucks) Run on Fuel Cells? Next-Gen Batteries? Both?


Toyota’s Project Portal and … a possibly “game-changing” semi from upstart Nikola Motors might prove FCEVs are the winning tech for the long-haul industry.

Last month, Tesla CEO Elon Musk rode onto the dais at Tesla’s design studio in Hawthorne, California aboard a futuristic semi truck.

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He exited the vehicle, collar popped, to introduce what looked to be a sleeker version of the colossal, decidedly unsexy commercial vehicles that rumble endlessly across America—and received the type of hysterical fanfare usually reserved for the Beyonces and Biebers of the world.

This marked one of the most anticipated, and curious, new-vehicle reveals of 2017: the Tesla Semi, a battery-electric-powered long-haul truck.

Tesla-Semi-truck-nikola-one

In his signature #humblebrag tone, Musk ticked off the Class 8 truck’s impressive capabilities: It can tow 80,000 pounds, the most allowed on US highways, for a range of 500 miles.

It has aerodynamics better than a Bugatti Chiron, a unique central seating position, and comes standard with enhanced AutoPilot, meaning it should never jackknife.

Also: it’s guaranteed not to break down for one million miles; it has a shatterproof windshield; and it implements a kinetic-energy-recovery system (KERS) in such a way that it will never need brake pads – in short WOW!

Plus, with a motor on each of the four rear wheels, it can rocket from 0-60 mph in five seconds flat—one-third the time of the average diesel semi.

Even fully loaded, that number increases to a scant 20 seconds, or a full minute faster than its smog-belching contemporaries. When towing up a five-percent grade, the Tesla can reach speeds of 65 mph, which is 20 mph faster than a diesel.

Taken in aggregate, these features and numbers would greatly benefit a trucker’s route in both speed and cost savings. They are eye-popping metrics; almost unbelievable. Which is perhaps why some are having a hard time believing them.

More important than what Musk said during his November announcement was what he didn’t say. For instance, there was no mention at all about the battery pack that will power the Tesla Semi to these magical thresholds. There was no mention of total weight or cost, which are arguably the two most important variables for long-haul shippers.

In terms of charging these unknown batteries, Musk promised a 400-mile recharge in the course of about 30 minutes. Based on recent estimates in Bloomberg New Energy Finance, hitting those numbers would require a charging system ten times more powerful than Tesla’s own Superchargers—currently the fastest consumer charging network in the world.

The cost building stations that could hit those figures would be profound, as would be the potential stress on the electrical system from multiple trucks charging simultaneously.

Bloomberg estimated that in order to fulfill Musk’s promises the truck would require a battery capacity between 600 and 1,000 kilowatt-hours.

Assuming a down-the-middle number of 800 kWh, that would necessitate a battery of more than 10,000 pounds, with a likely price tag north of $100,000. Musk also claims the Semi will be 20 percent less expensive than a diesel truck per mile—but that is with customers only paying $0.07/kWh.

Experts estimate that Tesla will have to pay, on average, a minimum of $0.40/kWh* for “green” electricity—meaning the company would have to heavily subsidize charging costs for fleets of trucks sucking down terawatts of electricity.

So, in order to hit Musk’s stated targets, Tesla will require batteries that don’t, as far as anyone knows, exist; charging capability faster than anything on the planet; and rates far below current market value.

 

“I don’t understand how that works,” electric vehicle analyst Salim Morsy told Bloomberg. “I really don’t.” Investor’s Business Daily dubbed Musk’s claims “monuments of envelope pushing.”

“The biggest concern that I have is that this is a typical Elon Musk ‘shiny object’ announcement to prop up Tesla’s stock price and distract from all of the issues he is having with Model 3 production,” an engineer associated with the hydrogen industry, who asked to remain anonymous, told us, referencing recent production delays and Tesla’s loss of over $1.3 billion year-to-date.

“I don’t mean to be negative; I do believe in battery technology and its merits, and I also believe that we will continue to see significant improvements in battery cost and performance during the coming decades.

But as a scientist and engineer I have always found Elon Musk’s lack of scientific accuracy and ability to overstate and exaggerate truth, and get away with it, very annoying and disingenuous.”

Tesla did not respond to requests to clarify these apparent discrepancies for this article.

The Truth About EV Trucks

Musk is not alone in the world of heavy-duty battery-electric trucks. VW recently announced a $1.7 billion investment towards developing electric powertrains for trucks and buses. Daimler, the world’s largest truck maker, unveiled an all-electric heavy-duty concept dubbed the E-FUSO Vision ONE at the Tokyo Motor Show, in late October. Daimler’s Class 8 truck promises a significantly more modest 220-mile range, with a payload 1.8 tons less than its diesel counterpart, and utilizing a 300 kWh battery pack. On paper, these figures make the E-FUSO Vision ONE more plausible than the Tesla Semi.

Project Portal Toyota maxresdefault

Of course Musk, a man who has promised to colonize Mars and builds spaceships to commute to the International Space Station, has never been known for making anything less than bold announcements.

But shorter-range BEV trucks do have a place in the transportation ecosystem. This is known as “last mile” and “short haul,” where deliveries are made inter-city, or within 100 miles. In such a capacity, the Tesla Semi could be greatly successful.

The semi truck business is a $30-billion-per-year industry in the United States alone, so there’s plenty of money to go around. But the Semi’s utility in true long-haul applications remains questionable.

Toyota’s Project Portal

 

Project Portal, a Real-World Zero-Emission Semi

Toyota has logged more than 4,000 development miles in a zero-emission Class 8 truck pulling drayage-rated cargo. This proof-of-concept semi, dubbed Project Portal, boasts 670 horsepower, 1,325 lb-ft of torque, and a 200-mile range. Rather than being powered strictly by battery pack—in this case, a comparatively small, 12kWh unit—Project Portal also utilizes twin fuel cell stacks plumbed from the Toyota Mirai consumer vehicle.

Project Portal II maxresdefault (2)

Project Portal has been moving goods around the Port of Los Angeles since April, and on October 23 expanded its routes to distribution warehouses and nearby rail yards. The idea is to collect data while the truck performs real-world drayage duties, its itineraries increasing as the study progresses.

Like the Tesla Semi, Project Portal also boasts impressive acceleration versus a traditional diesel truck: 8.9 seconds to travel 1/8th of a mile versus 14.6 seconds. Unlike the Tesla Semi, however, it’s already at work in the real world, even moving supplies and auto parts for Toyota throughout Southern California. Its numbers are verifiable.

In order to supply the Project Portal truck, as well as a growing fleet of FCEV semis as the project scales in size, Toyota announced last week that it would build the world’s first megawatt-scale hydrogen power station at the Port of Long Beach.

The power plant will generate 2.35 megawatts of electricity and 1.2 tons of hydrogen each day, enough to supply power and fuel to 2,350 homes and 1,500 FCEVs, respectively. Moreover, the Tri-Gen plant will generate so-called “green hydrogen” because it will be powered by 100-percent renewable sources, like local farm bio-waste. (Currently, most hydrogen is created via “cracking” natural gas, meaning splitting the CH4 into two H2 molecules and a free carbon atom.) Toyota could then claim the Project Portal trucks to be zero-emission from well-to-wheel.

Nikola Motors Arrives on the Scene With Bold Claims

 

A recent surprise player in the FCEV semi game is Utah-based Nikola Motors, makers of an announced Class 8 truck dubbed the Nikola One, a 320 kWh-powered tractor-trailer that will reportedly generate over 1,000-hp and 2,000 lb-ft of torque. Nikola Motors has also set the formidable goal of building a proprietary refueling station network across America, with over 700 planned H2 stations to be constructed in the next 10 years. As ambitious as that sounds, Nikola has an innovative business plan to scale up its stations. 

Nikola I Trevor-Milton-Nikola-Motor-CEO-on-truck

Nikola Motors CEO Trevor Milton

“We’re selling to fleets that run the same route every day,” says Nikola Motors CEO Trevor Milton. “So they’ll put an order in for 500 trucks, and we’ll build the stations before they come online.” A medium-size station will be constructed on each end of the route, allowing Nikola to establish flagship stations in each of those two terminal cities. With a range between 500 and 1,200 miles, depending on terrain, for their Nikola One, these stations can be quite far apart. Nikola plans to start with 16 stations located in the Midwest and East Coast, to be completed by 2019, at a cost of about $10 million apiece. Initially, there will be four test trucks running in 2018, with a planned 250 by 2019, and a total of 750 by 2020. Nikola plans to hit full production in 2021.

Rather than through a traditional lease, Nikola’s business model will be to charge customers solely on a per-mile basis. Nikola estimates the cost of a diesel semi runs between $1 to $1.25 per mile—this includes fuel, lease, tires, warranty, service, maintenance, etc.—though Milton says that with the Nikola One a driver is paying “anywhere between 20 to 40 percent less than that.”

“You don’t have to wait for 3 years to get your money back—you get your money back starting from day one,” Milton says.

While customers pay per mile (from $0.85 per mile for cheaper models up to $1.00/mile for the most expensive) all other costs of running the truck save insurance—from wipers and tires to all maintenance and fuel—are covered by Nikola Motors.

“That’s the golden egg,” Milton says. “How do you provide something that has no emission, that has better performance at less cost? And that’s what we’ve been able to do,” he says. “You won’t even be able to buy a diesel in 10 years because you’re going to be losing over a zero-emission vehicle.”

With over 8,000 trucks reserved in their first month of unveiling, Milton has no doubt they will have the necessary customers to fill out the initial 750 truck order, and more. “We’re on track, probably, to being more than 10-15 years booked out once we hit the assembly line,” he says. “We have more customers than we know what to do with.”

As far as Tesla’s news, Milton believes the Semi will be successful for short-haul work, estimating the truck’s real-world range will probably be around 350 miles—not nearly long enough for long-haul purposes.

“Their battery alone will weigh more than our entire truck,” he says, estimating the Semi’s lithium-ion pack will weigh about 15,000 pounds.

“We don’t really see them as a competitor on our end, just because our truck can outperform their truck in every category, every time, in every situation,” Milton says. “And [Nikola One can do] it two to three times further than they can, at a 10,000-pound weight difference. But it’s good that they’re coming in teaching people that electric can work, because we need all the help we can get in the industry to prove electric trucks work.”

Competitors or colleagues, Musk and Milton share a capacity for eyebrow-raising claims. When we first spoke with Milton in the spring for a longer feature on this site about the current state of the global hydrogen industry, he claimed he would require every Nikola station to produce 100 percent of its hydrogen via renewables like solar energy—a stipulation that would make the Nikola One, like Project Portal trucks fueled by the Tri-Gen bio-waste-powered plant, truly zero-emission from wheel to well.

“We will produce all the H2 on every one of our stations onsite via electrolysis,” Milton said at the time.

The math didn’t appear to add up. Using National Renewable Energy Laboratory (NREL) algorithms of energy production via solar cells, we deduced the lowest-capacity stations, at 12,500 kgs, would require a 540-acre solar farm to produce the necessary H2. We followed up with Nikola for clarification, and the company responded that, according to their calculations, they would each require “just over 218 acres.” Even with this considerable reduction, the idea that 700-plus stations across America would each be connected to a 218-acre solar fields seemed highly unlikely.

When we spoke more recently, Milton had softened his stance.

“I’ve definitely lessened on that, but it’s more of a philosophy, not as an actual message,” he said. “We have to take energy from the grid, but the way we get that energy is guaranteed that it’s zero-emission. We just don’t want a gigantic diesel plant powering our hydrogen.”

Instead, Milton now says, one-third of Nikola’s energy will be produced on-site, while the remainder will be bought from other green sources, whether that means from renewables, from power plants at excess capacity, or the grid via guaranteed zero-emission sources.

“There are multiple ways we’ll be buying and getting energy into our hydrogen production, but it’s not one-size-fits-all, that’s for sure. And if we made it sound like that, we apologize; we were mainly just trying to educate people that we are going to mandate that almost all of our energy is zero-emission from production to consumption.

“We’re evolving every month, as we get all these orders going in. We’re learning. There’s little things we’re tweaking, but ultimately our overall philosophy is it’s our duty and our goal to get rid of all the diesels and all the emissions on the road. And we’ll get there soon, it’ll just take some time.”

Regardless of the historical challenges inherent to starting any automotive brand, some people are hopeful about Nikola’s future.

“Building up a hydrogen eco-system entails many—and very different—elements,” says Yorgo Chatzimarkakis, Secretary General of the hydrogen-advocacy group Hydrogen Europe. After invoking the myriad doubts that Elon Musk faced when launching Tesla, he continues. “Some areas of a hydrogen-based economy need visionaries who have ambitions that do not seem plausible at the moment but are doable, and absolutely make sense in the long run.”

The Realities of a Zero-Emission Future

The point here isn’t to denigrate Tesla specifically, or BEVs in general. In order to achieve a zero emission transportation future—the goal of an increasing number of nations worldwide—many think that we should not have to choose between BEVs and FCEVs. Each has its clear advantages. 

As we’ve outlined in detail before, a zero-emission future will likely require the right solution for specific applications. Battery-electric power excels in smaller vehicles and for shorter ranges, while FCEVs are better suited for heavy-duty jobs that demand intense energy consumption and longer ranges. It need not be a zero-sum game.

Musk has accomplished enough already to warrant the benefit of the doubt for his bold Semi claims. Just this summer, he made a bet on Twitter that he could install a 100-megawatt battery storage facility in the South Australian outback within 100 days—or it would be free. Many doubted the billionaire futurist’s wager, but sure enough, by December 1 the facility was online and functional. During his comet-streak career he has made a habit of unflinching claims doubted by the masses, and has often enough enjoyed the last laugh.

However, Musk also has a history of disparaging hydrogen and FCEVs as legitimate transportation alternatives, calling them “incredibly dumb” and “bullshit.” This position is not only erroneous and misleading, but also dangerous and counterproductive to the same zero-emission future that he repeatedly touts. As the founder and CEO of the most valuable BEV company in the world by far—in fact, Wall Street considers Tesla the most valuable American automaker, having surpassed General Motors in April—it benefits him tremendously if that future is strictly BEV-powered.

The potential problem with Musk’s Semi assertions wouldn’t be that they’re possible embellishments about the capabilities of a BEV truck—he certainly wouldn’t be the first CEO to promise the impossible to prop up stock value—as much as their potential to salt the earth for FCEV semi truck growth. Claiming that BEV semis are a better solution than FCEVs would be fine on a barstool or in a vacuum, but the incredible power of Musk’s voice in the tech and transportation markets could devalue the viability of Class 8 vehicles powered by fuel cells.

Case in point: Bloomberg reported that immediately after Musk’s Tesla Semi announcement, share prices of truck and truck component makers dropped. They recovered when analysts had time to sift through the available information, but Musk potentially hobbling a critical cog of a zero-emission future runs contrary to his stated goals of saving the planet.

In the end, if Tesla, Daimler, Toyota and Nikola can get their respective FCEV and BEV semis off the ground, the impact would be tectonic. Using average estimates, every single alternative-powertrain truck replacing a similar ICE-powered vehicle would remove about 173 tons of CO2 emissions each year. Scale that to a fleet of 1,000, or 100,000, or a million trucks, and the impact on the climate and air quality would be profound. Musk should be free to do what he needs to in order to ensure his company succeeds, except when it values Tesla’s bottom line over that of the planet.

*Note: This article was updated to reflect that the stated price of $0.40/kWh is specifically for so-called “green” electricity harnessed from renewable or zero-emission sources.

UCLA: Solar supercapacitor creates electricity and hydrogen fuel on the cheap


Hydrogen-powered vehicles are slowly hitting the streets, but although it’s a clean and plentiful fuel source, a lack of infrastructure for mass producing, distributing and storing hydrogen is still a major roadblock.

But new work out of the University of California, Los Angeles (UCLA) could help lower the barrier to entry for consumers, with a device that uses sunlight to produce both hydrogen and electricity.

The UCLA device is a hybrid unit that combines a supercapacitor with a hydrogen fuel cell, and runs the whole shebang on solar power.

Along with the usual positive and negative electrodes, the device has a third electrode that can either store energy electrically or use it to split water into its constituent hydrogen and oxygen atoms – a process called water electrolysis.

To make the electrodes as efficient as possible, the team maximized the amount of surface area that comes into contact with water, right down to the nanoscale. That increases the amount of hydrogen the system can produce, as well as how much energy the supercapacitor can store.

“People need fuel to run their vehicles and electricity to run their devices,” says Richard Kaner, senior author of the study. “Now you can make both fuel and electricity with a single device.”

Hydrogen itself may be clean, but producing it on a commercial scale might not be. It’s often created by converting natural gas, which not only results in a lot of carbon dioxide emissions but can be costly.

Using renewable sources like solar can help solve both of those problems at once. And it helps that the UCLA device uses materials like nickel, iron and cobalt, which are much more abundant than the precious metals like platinum that are currently used to produce hydrogen.

“Hydrogen is a great fuel for vehicles: It is the cleanest fuel known, it’s cheap and it puts no pollutants into the air – just water,” says Kaner. “And this could dramatically lower the cost of hydrogen cars.”

The new system could also help solve some of the infrastructure woes as well. Hydrogen vehicles can’t really take off until consumers can easily find places to fill up, and while strides are being made in that department, with the UCLA device users can hook into the sun almost anywhere to produce their own fuel, which could be particularly handy for those living in rural or remote areas.

As an added bonus, the supercapacitor part of the system can chemically store the harvested solar energy as hydrogen. Doing so could help bolster energy storage for the grid. Although the current device is palm-sized, the researchers say that it should be relatively easy to scale up for those applications.

The research was published in the journal Energy Storage Materials.

Source: UCLA

The Fuel Tank of Tomorrow – A Super Capacitor? +YouTube Video


 

KiloWatt Labs CEO Omer Ghani explains in the above interview, filmed at the IDTechEX Show!, that his company has overcome these challenges and has begun shipping large-scale, super capacitor-based energy storage solutions for applications such as microgrid, renewable, utility and mobility. He indicates their solution is a cost-competitive replacement for traditional battery approaches,

 

New Efficient, Low-Temperature Catalyst for Converting Water and CO to Hydrogen Gas and CO2


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Brookhaven Lab chemists Ping Liu and José Rodriguez helped to characterize structural and mechanistic details of a new low-temperature catalyst for producing high-purity hydrogen gas from water and carbon monoxide.

Low-temperature “water gas shift” reaction produces high levels of pure hydrogen for potential applications, including fuel cells

UPTON, NY—Scientists have developed a new low-temperature catalyst for producing high-purity hydrogen gas while simultaneously using up carbon monoxide (CO). The discovery—described in a paper set to publish online in the Journal Science — could improve the performance of fuel cells that run on hydrogen fuel but can be poisoned by CO.

“This catalyst produces a purer form of hydrogen to feed into the fuel cell,” said José Rodriguez, a chemist at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory. Rodriguez and colleagues in Brookhaven’s Chemistry Division—Ping Liu and Wenqian Xu—were among the team of scientists who helped to characterize the structural and mechanistic details of the catalyst, which was synthesized and tested by collaborators at Peking University in an effort led by Chemistry Professor Ding Ma.

“This catalyst produces a purer form of hydrogen to feed into fuel cells.”

— José Rodriguez

Because the catalyst operates at low temperature and low pressure to convert water (H2O) and carbon monoxide (CO) to hydrogen gas (H2) and carbon dioxide (CO2), it could also lower the cost of running this so-called “water gas shift” reaction.

“With low temperature and pressure, the energy consumption will be lower and the experimental setup will be less expensive and easier to use in small settings, like fuel cells for cars,” Rodriguez said.

The gold-carbide connection

The catalyst consists of clusters of gold nanoparticles layered on a molybdenum-carbide substrate. This chemical combination is quite different from the oxide-based catalysts used to power the water gas shift reaction in large-scale industrial hydrogen production facilities.

“Carbides are more chemically reactive than oxides,” said Rodriguez, “and the gold-carbide interface has good properties for the water gas shift reaction; it interacts better with water than pure metals.”

operando x-ray diffraction studies of the gold-molybdenum-carbide catalyst over a range of temperatuClick on the image to download a high-resolution version.Wenqian Xu and José Rodriguez of Brookhaven Lab and Siyu Yao, then a student at Peking University but now a postdoctoral research fellow at Brookhaven, conducted operando x-ray diffraction studies of the gold-molybdenum-carbide catalyst over a range of temperatures (423 Kelvin to 623K) at the National Synchrotron Light Source (NSLS) at Brookhaven Lab. The study revealed that at temperatures above 500K, molybdenum-carbide transforms to molybdenum oxide, with a reduction in catalytic activity.

 

“The group at Peking University discovered a new synthetic method, and that was a real breakthrough,” Rodriguez said. “They found a way to get a specific phase—or configuration of the atoms—that is highly active for this reaction.”

Brookhaven scientists played a key role in deciphering the reasons for the high catalytic activity of this configuration. Rodriguez, Wenqian Xu, and Siyu Yao (then a student at Peking University but now a postdoctoral research fellow at Brookhaven) conducted structural studies using x-ray diffraction at the National Synchrotron Light Source (NSLS) while the catalyst was operating under industrial or technical conditions. These operandoexperiments revealed crucial details about how the structure changed under different operating conditions, including at different temperatures.

With those structural details in hand, Zhijun Zuo, a visiting professor at Brookhaven from Taiyuan University of Technology, China, and Brookhaven chemist Ping Liu helped to develop models and a theoretical framework to explain why the catalyst works the way it does, using computational resources at Brookhaven’s Center for Functional Nanomaterials (CFN).

“We modeled different interfaces of gold and molybdenum carbide and studied the reaction mechanism to identify exactly where the reactions take place—the active sites where atoms are binding, and how bonds are breaking and reforming,” she said.

Additional studies at Oak Ridge National Laboratory’s Center for Nanophase Materials Sciences (CNMS), the Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory, and two synchrotron research facilities in China added to the scientists’ understanding.

“This is a multipart complex reaction,” said Liu, but she noted one essential factor: “The interaction between the gold and the carbide substrate is very important. Gold usually bonds things very weakly. With this synthesis method we get stronger adherence of gold to molybdenum carbide in a controlled way.”

That configuration stabilizes the key intermediate that forms as the reaction proceeds, and the stability of that intermediate determines the rate of hydrogen production, she said.

The Brookhaven team will continue to study this and other carbide catalysts with new capabilities at the National Synchrotron Light Source II (NSLS-II), a new facility that opened at Brookhaven Lab in 2014, replacing NSLS and producing x-rays that are 10,000 times brighter. With these brighter x-rays, the scientists hope to capture more details of the chemistry in action, including details of the intermediates that form throughout the reaction process to validate the theoretical predictions made in this study.

The work at Brookhaven Lab was funded by the U.S. DOE Office of Science.

Additional funders for the overall research project include: the National Basic Research Program of China, the Chinese Academy of Sciences, National Natural Science Foundation of China, Fundamental Research Funds for the Central Universities of China, and the U.S. National Science Foundation.

NSLS, NSLS-II, CFN, CNMS, and ALS are all DOE Office of Science User Facilities.

Brookhaven National Laboratory is supported by the Office of Science of the U.S. Department of Energy.  The Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time.  For more information, please visit science.energy.gov.

A Hydrogen Fuel-Powered Truck hits the Road, emitting only Water Vapor!


Hydrogen Truck Project-Portal-Toyota-fuel-cell-truck-full-grilleA concept truck by Toyota is powered by hydrogen fuel cells and emits nothing but water vapor. Photo Credit: Toyota

 

Vehicles powered by alternatives to fossil fuel are on the roll. Literally. The Japanese automaker Toyota is rolling out a new line of vehicles powered by hydrogen fuel cells. A concept version of a long-haul truck with the car manufacturer’s new hydrogen-based engine in it will set out with a full load of cargo from Los Angeles and make its way to Long Beach.

“If you see a big-rig driving around the Ports of Los Angeles and Long Beach that seems oddly quiet and quick, do not be alarmed! It’s just the future,” Toyota quips in a statement issued to the press. The trial is part of the Japanese company’s feasibility studies for its brand-new “Project Portal” – a hydrogen fuel cell systemdesigned for heavy-duty trucks. Toyota touts its Project Portal as the next step in its development of zero-emission fuel cell technology for industrial uses.

“[The trial’s] localized, frequent route patterns are designed to test the demanding drayage duty-cycle capabilities of the fuel cell system while capturing real world performance data,” Toyota explains  of its upcoming test runs. “As the study progresses, longer haul routes will be introduced.”

Toyota’s heavy-duty concept truck boasts a beast of an engine with more than 670 horsepower and 1,325 pound feet of torque thanks to a pair of Mirai fuel cell stacks and a relatively small 12kWh battery. The truck’s gross weight capacity is over 36,000kg while its projected driving range is more than 320km per fill under normal drayage conditions.

Comparable long-haul trucks, if powered by gasoline, emit plenty of CO2. Not this new one, though. “The zero-emission class 8 truck proof of concept has completed more than 4,000 successful development miles, while progressively pulling drayage rated cargo weight, and emitting nothing but water vapor,” the company explains.

You’ve read that right: the truck will emit water vapor and nothing else. This means that the technology, once it is put into use on a wider scale, can help us reduce our CO2 emissions in an effort to mitigate the effects of climate change.

NREL: Demonstrating and Advancing Benefits of Hydrogen Technology



by Bryan S. Pivovar, Ph.D, H2@Scale Lead/Group Manager, Chemistry and Nanosciences Center, National Renewable Energy Laboratory

Over the past several decades, technological advancements and cost reductions have dramatically changed the economic potential of hydrogen in our energy system. 
Fuel cell electric vehicles are now available for commercial sale and hydrogen stations are open to the public (more than 2,000 fuel cell vehicles are on the road and more than 30 fueling stations are open to the public in California). 

Low-cost wind and solar power are quickly changing the power generation landscape and creating a need for technologies that enhance the flexibility of the grid in the mid- to long-term.

The vision of a clean, sustainable energy system with hydrogen serving as the critical centerpiece is the focus of H2@Scale, a major initiative involving multiple U.S. Department of Energy (DOE) program offices, led by DOE’s Fuel Cell Technologies Office in the Office of Energy Efficiency and Renewable Energy, and 14 DOE national laboratories. 

H2@Scale expands the focus of hydrogen technologies beyond power generation and transportation, to grid services and industrial processes that use hydrogen.

The Energy Systems Integration Facility (ESIF) at the National Renewable Energy Laboratory (NREL) serves as a world-class, sophisticated testbed to evaluate and advance the H2@Scale concept. 

The ESIF is a DOE user facility interacting with multiple industrial stakeholders to accelerate the adoption of clean energy, including hydrogen-based technologies. Many of the barriers for making the H2@Scale vision a reality are being addressed today within ESIF by NREL researchers along with other industrial and national laboratory collaborators. 

The unique testbed capabilities at NREL and collaborating national labs are now available for use by industry and several partnerships are currently in development.
Within the ESIF, NREL researchers use electrons and water to produce hydrogen at rates of up to 100 kg/day (enough to fuel ~6,000 miles of travel in today’s fuel cell electric vehicles or more than 20 cars) with plans to expand capacity to four times this level. 

The hydrogen produced is compressed and stored in the 350 kg of on-site storage available at pressures as high as 12,500 psi. The hydrogen is used in multiple applications at the ESIF, including fueling fuel cell electric vehicles, testing and validating hydrogen infrastructure components and systems, producing renewable natural gas (through biological reaction with carbon dioxide), and as a feedstock for fuel cell power generation and research and development efforts.

To accelerate the H2@Scale concept, the cost, performance, and durability of hydrogen production, infrastructure (distribution and storage), and end use technologies need to be improved. NREL researchers, along with other labs, are actively demonstrating and advancing hydrogen technology in a number of areas including low-temperature electrolysis, biological production of renewable natural gas, and infrastructure.

Renewable hydrogen via low-temperature electrolysis




Today’s small-scale electrolysis systems are capable of producing several kilograms (kg) of hydrogen per day, but can cost as much as $10 per watt. At larger scale, megawatt (MW) systems producing more than 400 kg per day can cost under $2 per watt. However, for low-temperature electrolyzer systems to compete with the established steam methane reforming process for hydrogen production, the capital cost needs to be reduced to far below $1 per watt.

NREL has ongoing collaborations with Idaho National Laboratory (INL) to demonstrate control of a 250-kW electrolyzer system in a real-time grid simulation using a hardware-in-the-loop (HIL)-based approach to verify the performance of electrolyzer systems in providing grid support. HIL couples modeling and hardware in real-time simulations to better understand the performance of complex systems. 

The electrolyzer system, a building block for megawatt-scale deployment, was remotely controlled based on simulations of signals from a power grid. NREL and INL engineers demonstrated the ability of an electrolyzer to respond to grid signals in sub-seconds, making electrolyzers a viable candidate for “demand response” technologies that help control frequency and voltage on the grid by adjusting their power intake based on grid signals. 

A key enabler of low-cost electrolysis will be for electrolyzer technologies to respond dynamically to grid signals, such that they access low-cost power when available. The potential performance and durability implications of such dynamic operation are being elucidated in ongoing tests. Such experiments are essential to assess the potential for electrolyzers to support grid resiliency and to identify remaining R&D needs toward this value proposition.
NREL’s scientists are developing and exploring new materials for electrolysis systems, including advanced catalysts based on nanowire architecture and alkaline membranes, and approaches for integrating these materials into low-cost, durable membrane electrode assemblies.  

Graphene-wrapped nanocrystals may open door toward next-gen fuel cells



Ultra-Thin  oxide layer (oxygen atoms shown in red) coating graphene-wrapped magnesium nanoparticles (orange) still allows in hydrogen atoms (blue) for hydrogen storage applications

Researchers at the Department of Energy’s Lawrence Berkeley National Laboratory have developed a mix of metal nanocrystals wrapped in graphene that may open the door to the creation of a new type of fuel cell by enabling enhanced hydrogen storage properties.

Graphene-Wrapped Nanocrystals Make Inroads Toward Next-Gen Fuel Cells



Ultra-thin oxide layer (oxygen atoms shown in red) coating graphene-wrapped magnesium nanoparticles (orange) still allows in hydrogen atoms (blue) for hydrogen storage applications

The team studied how graphene can be used as both selective shielding, as well as a performance increasing factor in terms of hydrogen storage. 

The study drew upon a range of Lab expertise and capabilities to synthesize and coat the magnesium crystals, which measure only 3-4 nanometers (billionths of a meter) across; study their nanoscale chemical composition with X-rays; and develop computer simulations and supporting theories to better understand how the crystals and their carbon coating function together.

Reduced graphene oxide (or rGO) has nanoscale holes that permit hydrogen to pass through while keeping larger molecules away. This carbon wrapping was intended to prevent the magnesium – which is used as a hydrogen storage material – from reacting with its environment, including oxygen, water vapor and carbon dioxide. 

Such exposures could produce a thick coating of oxidation that would prevent the incoming hydrogen from accessing the magnesium surfaces. 

The study, however, suggests that an atomically thin layer of oxidation did form on the crystals during their preparation. Surprisingly, this oxide layer doesn’t seem to degrade the material’s performance.

The study’s lead author stated “Most people would suspect that the oxide layer is bad news for hydrogen storage, which it turns out may not be true in this case. Without this oxide layer, the reduced graphene oxide would have a fairly weak interaction with the magnesium, but with the oxide layer the carbon-magnesium binding seems to be stronger. 

That’s a benefit that ultimately enhances the protection provided by the carbon coating. There doesn’t seem to be any downside”.

The researchers noted that the current generation of hydrogen-fueled vehicles power their fuel cell engines using compressed hydrogen gas. “This requires bulky, heavy cylindrical tanks that limit the driving efficiency of such cars”, and the nanocrystals offer one possibility for eliminating these bulky tanks by storing hydrogen within other materials.

More Durable – Less Expensive Fuel Cells Speeds the Commercialization of FC Vehicles – U. of Delaware


vehicles-cars-hydrogen-fuel-cellResearchers have developed a new technology that could speed up the commercialization of fuel cell vehicles

Summary: A new technology has been created that could make fuel cells cheaper and more durable. Hydrogen-powered fuel cells are a green alternative to internal combustion engines because they produce power through electro-chemical reactions, leaving no pollution behind. Platinum is the most common catalyst in the type of fuel cells used in vehicles, but it’s expensive. The UD team used a novel method to come up with a less expensive catalyst.

A team of engineers at the University of Delaware has developed a technology that could make fuel cells cheaper and more durable, a breakthrough that could speed up the commercialization of fuel cell vehicles.

They describe their results in a paper published in Nature Communications.

Hydrogen-powered fuel cells are a green alternative to internal combustion engines because they produce power through electrochemical reactions, leaving no pollution behind.

Materials called catalysts spur these electro-chemical reactions. Platinum is the most common catalyst in the type of fuel cells used in vehicles.F Cell Car images

However, platinum is expensive — as anyone who’s shopped for jewelry knows. The metal costs around $30,000 per kilogram.

Instead, the UD team made a catalyst of tungsten carbide, which goes for around $150 per kilogram. They produced tungsten carbide nanoparticles in a novel way, much smaller and more scalable than previous methods.

“The material is typically made at very high temperatures, about 1,500 Celsius, and at these temperatures, it grows big and has little surface area for chemistry to take place on,” said Dionisios Vlachos, director of UD’s Catalysis Center for Energy Innovation.. “Our approach is one of the first to make nanoscale material of high surface area that can be commercially relevant for catalysis.”

The researchers made tungsten carbide nanoparticles using a series of steps including hydrothermal treatment, separation, reduction, carburization and more.

“We can isolate the individual tungsten carbide nanoparticles during the process and make a very uniform distribution of particle size,” said Weiqing Zheng, a research associate at the Catalysis Center for Energy Innovation.

Next, the researchers incorporated the tungsten carbide nanoparticles into the membrane of a fuel cell. Automotive fuel cells, known as proton exchange membrane fuel cells (PEMFCs), contain a polymeric membrane. This membrane separates the cathode from the anode, which splits hydrogen (H2) into ions (protons) and delivers them to the cathode, which puts out current.

The plastic-like membrane wears down over time, especially if it undergoes too many wet/dry cycles, which can happen easily as water and heat are produced during the electrochemical reactions in fuel cells.

When tungsten carbide is incorporated into the fuel cell membrane, it humidifies the membrane at a level that optimizes performance.

“The tungsten carbide catalyst improves the water management of fuel cells and reduces the burden of the humidification system,” said Liang Wang, an associate scientist in the Department of Mechanical Engineering.

The team also found that tungsten carbide captures damaging free radicals before they can degrade the fuel cell membrane. As a result, membranes with tungsten carbide nanoparticles last longer than traditional ones.

“The low-cost catalyst we have developed can be incorporated within the membrane to improve performance and power density,” said . “As a result, the physical size of the fuel cell stack can be reduced for the same power, making it lighter and cheaper. Furthermore, our catalyst is able to deliver higher performance without sacrificing durability, which is a big improvement over similar efforts by other groups.”

The UD research team used innovative methods to test the durability of a fuel cell made with tungsten carbide. They used a scanning electron microscope and focused ion beam to obtain thin-slice images of the membrane, which they analyzed with software, rebuilding the three-dimensional structure of the membranes to determine fuel cell longevity.

The group has applied for a patent and hopes to commercialize their technology.

“This is a very good example of how different groups across departments can collaborate,” Zheng said.

Story Source:

Materials

provided by University of DelawareNote: Content may be edited for style and length.


Journal Reference:

  1. Weiqing Zheng, Liang Wang, Fei Deng, Stephen A. Giles, Ajay K. Prasad, Suresh G. Advani, Yushan Yan, Dionisios G. Vlachos. Durable and self-hydrating tungsten carbide-based composite polymer electrolyte membrane fuel cellsNature Communications, 2017; 8 (1) DOI: 10.1038/s41467-017-00507-6