Accelerating Innovation in Alberta


U of Alberta 140618-emerald-awards-ualberta-sign-teaserUAlberta partnership with TEC Edmonton, Innovate Calgary receives federal funding to help grow promising startups. By TEC Edmonton Staff on June 24, 2014 (Edmonton)

A partnership of the University of Alberta, TEC Edmonton and Innovate Calgary has been selected by the Canadian Accelerator and Incubator Program to help business accelerators and incubators deliver their services to promising Canadian firms.

TEC Edmonton, Edmonton’s leading business incubator and accelerator, will offer additional business services to health-based startup companies, including new companies spun off from medical research at the U of A. Innovate Calgary, TEC Edmonton’s counterpart in Calgary, will focus its funding on energy-related high-tech startups.

With the U of A, the two business incubator/accelerators will also put the new funding to work by linking investment-ready new companies to existing investor networks focused on new, made-in-Alberta technologies.

U of Alberta 140618-emerald-awards-ualberta-sign-teaser

“This is fantastic news,” said Lorne Babiuk, vice-president (research) at the U of A. “It’s another example of how the University of Alberta continues to transfer its knowledge, discoveries and technologies into the community via commercialization to benefit society, the economy and Canada as a whole. We are delighted to be partnering with Innovate Calgary and TEC Edmonton, which are Alberta’s largest and most successful incubators, and among the best in the country. I thank the Government of Canada for their support and for this valuable program.” “CAIP funding allows us and our partners to enhance and expand our services supporting the innovation community and Alberta’s overall economic prosperity,” said Peter Garrett, president of Innovate Calgary.

“With our shareholders the University of Calgary, the Calgary Chamber and the City of Calgary, Innovate Calgary is committed to accelerating the growth of early-stage companies and entrepreneurs.” “TEC Edmonton is a true community partnership,” said TEC Edmonton CEO Chris Lumb. “We were created by the University of Alberta and the City of Edmonton (through the Edmonton Economic Development Corporation) with strong support from the regional entrepreneurial community, technology investors, the Province of Alberta, the Canadian government and hundreds of volunteers.

With such support, TEC Edmonton has grown into one of Canada’s best tech accelerators. “This new federal funding strengthens TEC Edmonton and Innovate Calgary’s ability to help grow great new companies and to further commercialize research at Alberta’s post-secondary institutions.”

– See more at: http://uofa.ualberta.ca/news-and-events/newsarticles/2014/june/accelerating-innovation-in-alberta#sthash.whh0XCx4.dpuf

Why IBM and Intel Are Chasing the $100B Opportunity in Nanophotonics


Printing Graphene ChipsPeter De Dobbelaere, PhD has spent nearly two decades at the intersection of optics and electronics. He is currently Vice President of Engineering at Luxtera – a market leader in Silicon Photonics (Full disclosure: my venture firm Lux Capital is an equity investor in Luxtera). We sat down for an exclusive interview to understand the state of the industry.

Nanophotonics sounds complex. How would you explain this technology to someone you met in the supermarket?

The idea behind Nanophotonics (or Silicon Photonics) is actually quite simple: take the world’s fastest communication technology (light), and build it directly into semiconductor chips using well-known and massively scalable production processes.

The goal is to take the same optics functions that have traditionally been done with esoteric and expensive parts and processes and bring them into a regular chip fabrication facility. This allows you to build off of the existing multibillion-dollar investments made by the semiconductor industry, instead of having to create a new manufacturing line for every new product. It also allows for integration with other computer circuits – combining many valuable functions into one small package.

These manufacturing platforms and broad scale integration are the same key drivers that have enabled the industry to produce low cost iPhones, tablets, and laptop PCs, as well as the millions of servers, switches, and routers that power the Internet. As we build the next generations of servers and connect them together, we need a technology like Silicon Photonics to leverage that same infrastructure to meet the incredible demand for high-speed data throughput at an acceptable cost.

IBM recently made a big announcement in this space. What are they working on?

This is an area IBM cares about because the rapid expansion of bandwidth in datacenters is creating many challenges that Silicon Photonics are likely to play a fundamental role in addressing. While the press release did not provide too many specific details, IBM did announce an important accomplishment in successfully integrating photonics on standard CMOS circuits. This is equivalent to a milestone Luxtera hit over four years ago, prior to entering full production with our technology.

How does Luxtera’s technology differ from IBM’s?

In some aspects, the technology announced by IBM is similar to what Luxtera announced in 2008 – it is based on a standard 200mm CMOS process in a commercial fabrication facility. It is likely that this technology, like Luxtera’s, can be used to build optical transceiver chips operating in the 10Gb data rate.

Printing Graphene Chips

What is unclear is how IBM plans to build actual products. In addition to the Silicon Photonics processes and chip design, Luxtera has developed a suitable light source and cost effective methods to get light in and out of the chips and how to package these cost effectively in a product. IBM also talks about using multiple wavelengths (WDM) of light in their devices. This is an approach we demonstrated in 2007, but through extensive work in commercializing the technology to meet customer needs, we’ve focused on more low-power and cost-effective solutions using a single-wavelength laser for multiple channels. To enhance bandwidth further, the single-wavelength approach is extensible through the use of advanced modulation similar to what the industry has used for electrical interconnect to keep costs down as bandwidth increases.

IBM announced chips made on a 90-nanometer process – what does that mean?

90-nanometers refers to the feature size for the design process they are using. In simple terms, smaller is usually better (our continued ability to shrink our circuits have helped give rise to Moore’s Law – doubling chip performance every 18 months). 90nm is far from our latest technology node – the industry is already working on 14nm processes.

In 2008, Luxtera also produced a fully-integrated device on a similar process, but we deemed these “older transistors” too slow for next generation applications that require 25Gb speed. So instead of trying to chase Moore’s law, we believe the industry will evolve to use a hybrid approach – integrating the latest transistors from any factory with Silicon Photonics. This approach is similar to trends we see in high-volume wireless chipsets, allowing increased flexibility to designers. It is doubtful that fully-integrated 90nm chips will enable power efficient operation at the data rates the industry is demanding.

 

What are the latest developments inside Luxtera?

Luxtera has been making critical progress in both R&D and volume production; we recently began sampling the industry’s 1st 100Gb chipset. Additionally, we announced that we shipped over 1 million 10Gb channels. We continue volume production today of our 40Gb and 56Gb products, and will end the year having shipped over 2 million total channels and amassed a mountain of production data. This experience is enabling a platform capable of delivering tens of millions of devices a year.

Where are so many devices being used?

Many system-makers are beginning to replace the interfaces that traditionally used copper wires with optical fibers. One good example are the backplanes for servers and switches within data centers – our chips are enabling the transition from copper to fiber optics and are slated to drive those fibers.

We are also seeing that Luxtera’s Silicon Photonics technology platform is going to play a pivotal role in the adoption of 100Gb speeds in the data center. A key issue here is interconnecting the countless servers that make up the cloud. The architectures favored by these installations require connections that span 100-500 meters. As you push the data rate to 100Gb, the industry has found that legacy technologies such as copper traces and multimode fiber are unable to deliver. This is helping to catalyze significant demand for our 100Gb products.

What about Intel’s efforts in this area?

Both IBM and Intel have done outstanding work in silicon photonics. As clear leaders in semiconductors, they recognize the need to move Silicon Photonics from R&D towards production.  Both companies are playing with different designs and architectures. We believe that these companies will run into similar constraints as we did when we brought this technology through commercialization.

When do you see a broad transition to Silicon Photonics taking place?

This is a very exciting place to be right now. Marquee system vendors are starting to demand this technology (as evidenced by Cisco’s recent acquisition of Silicon Photonics startup Lightwire). I don’t have any crystal ball, but I fully expect Silicon Photonics and Luxtera to be playing a significant role in the datacenter, mobile data and cloud data expansion in the next few years.

Nanoparticles Stagger Delivery of Two Drugs: Knock Out Aggressive Cancer Tumors


 

Nano Cancer id36068Chemotherapy timing is key to success: Nanoparticles that stagger delivery of two drugs knock out aggressive tumors in mice.

Cambridge, MA | Posted on May 8th, 2014

 

Abstract:


MIT researchers have devised a novel cancer treatment that destroys tumor cells by first disarming their defenses, then hitting them with a lethal dose of DNA damage.

In studies with mice, the research team showed that this one-two punch, which relies on a nanoparticle that carries two drugs and releases them at different times, dramatically shrinks lung and breast tumors. The MIT team, led by Michael Yaffe, the David H. Koch Professor in Science, and Paula Hammond, the David H. Koch Professor in Engineering, describe the findings in the May 8 online edition of Science Signaling.

“I think it’s a harbinger of what nanomedicine can do for us in the future,” says Hammond, who is a member of MIT’s Koch Institute for Integrative Cancer Research. “We’re moving from the simplest model of the nanoparticle — just getting the drug in there and targeting it — to having smart nanoparticles that deliver drug combinations in the way that you need to really attack the tumor.”

BioGraphene-320

Doctors routinely give cancer patients two or more different chemotherapy drugs in hopes that a multipronged attack will be more successful than a single drug. While many studies have identified drugs that work well together, a 2012 paper from Yaffe’s lab was the first to show that the timing of drug administration can dramatically influence the outcome.

In that study, Yaffe and former MIT postdoc Michael Lee found they could weaken cancer cells by administering the drug erlotinib, which shuts down one of the pathways that promote uncontrolled tumor growth. These pretreated tumor cells were much more susceptible to treatment with a DNA-damaging drug called doxorubicin than cells given the two drugs simultaneously.

“It’s like rewiring a circuit,” says Yaffe, who is also a member of the Koch Institute. “When you give the first drug, the wires’ connections get switched around so that the second drug works in a much more effective way.”

Erlotinib, which targets a protein called the epidermal growth factor (EGF) receptor, found on tumor cell surfaces, has been approved by the Food and Drug Administration to treat pancreatic cancer and some types of lung cancer. Doxorubicin is used to treat many cancers, including leukemia, lymphoma, and bladder, breast, lung, and ovarian tumors.

Staggering these drugs proved particularly powerful against a type of breast cancer cell known as triple-negative, which doesn’t have overactive estrogen, progesterone, or HER2 receptors. Triple-negative tumors, which account for about 16 percent of breast cancer cases, are much more aggressive than other types and tend to strike younger women.

That was an exciting finding, Yaffe says. “The problem was,” he adds, “how do you translate that into something you can actually give a cancer patient?”

From lab result to drug delivery

To approach this problem, Yaffe teamed up with Hammond, a chemical engineer who has previously designed several types of nanoparticles that can carry two drugs at once. For this project, Hammond and her graduate student, Stephen Morton, devised dozens of candidate particles. The most effective were a type of particle called liposomes — spherical droplets surrounded by a fatty outer shell.

The MIT team designed their liposomes to carry doxorubicin inside the particle’s core, with erlotinib embedded in the outer layer. The particles are coated with a polymer called PEG, which protects them from being broken down in the body or filtered out by the liver and kidneys. Another tag, folate, helps direct the particles to tumor cells, which express high quantities of folate receptors.

Once the particles reach a tumor and are taken up by cells, the particles start to break down. Erlotinib, carried in the outer shell, is released first, but doxorubicin release is delayed and takes more time to seep into cells, giving erlotinib time to weaken the cells’ defenses. “There’s a lag of somewhere between four and 24 hours between when erlotinib peaks in its effectiveness and the doxorubicin peaks in its effectiveness,” Yaffe says.

The researchers tested the particles in mice implanted with two types of human tumors: triple-negative breast tumors and non-small-cell lung tumors. Both types shrank significantly. Furthermore, packaging the two drugs in liposome nanoparticles made them much more effective than the traditional forms of the drugs, even when those drugs were given in a time-staggered order.

As a next step before possible clinical trials in human patients, the researchers are now testing the particles in mice that are genetically programmed to develop tumors on their own, instead of having human tumor cells implanted in them.

The researchers believe that time-staggered delivery could also improve other types of chemotherapy. They have devised several combinations involving cisplatin, a commonly used DNA-damaging drug, and are working on other combinations to treat prostate, head and neck, and ovarian cancers. At the same time, Hammond’s lab is working on more complex nanoparticles that would allow for more precise loading of the drugs and fine-tuning of their staggered release.

“With a nanoparticle delivery platform that allows us to control the relative rates of release and the relative amounts of loading, we can put these systems together in a smart way that allows them to be as effective as possible,” Hammond says.

Morton and Lee are the lead authors of the Science Signaling paper. Postdocs Zhou Deng, Erik Dreaden, and Kevin Shopsowitz, visiting student Elise Siouve, and graduate student Nisarg Shah also contributed to the research. The work was funded by the National Institutes of Health, the Center for Cancer Nanotechnology Excellence, and a Breast Cancer Alliance Exceptional Project Grant.

Written by Anne Trafton, MIT News Office

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Copyright © Massachusetts Institute of Technology

Nanotechnology may change how we grow food


Food and NT 4153936-3x2-340x227Nanotechnology, the science of working with extremely small particles, may soon help keep our food fresh for longer as well as create entirely new ways to produce food through photosynthesis.

 

As one example, nanoparticles of silver, which are so small that you can fit a million of them into a grain of sand, can be used in food packing as an anti-bacterial agent to extend the shelf life of products.

Professor Thomas Faunce from the Australian National University says there’s a lot of promise in the technology, but there are some groups like Friends of the Earth that are concerned about it.

“Controversy continues, it’s easy to overstate the risks and I think that would be a mistake, but at the same time there’s no doubt that things like nanosilver for example, which decreases bacterial or vital contamination of food, can be extremely dangerous in terms of the waterways, in terms of interfering with the food chain.”

Professor Faunce says that one of the areas that is of the most interest to him is the possibility of artificial photosynthesis.

Food and NT 4153936-3x2-340x227

Nanotechnology may change the way we grow and eat our food.

 

“If we look at what we’re covering the planet with as a species, all the asphalt and roads and buildings, they’re all just bludging. The real thrust of artificial photosynthesis globally is to use every single road, house, bridge, to turn that into a structure that is doing photosynthesis more than plants.”

It may be a while before we see buildings coated in nanoparticles that could produce starch like foodstuffs via artificial photosynthesis, but Professor Faunce says he’s hoping a number of upcoming conferences will cement the importance of the idea.

Quantum Dots (QD) are Set to Explode in the Next 18 Months


atomsinananoQuantum dots (QD) are potentially set to explode in the next 18 months. Companies such as QD Vision and Nanosys have developed scalable solution production processes and are partnering with multi-national OEMs to use quantum dots in displays for consumer products. QDs warm up the colour of the light while increasing its quality (colour rendering index), delivering a superior blend of colour quality, lifetime and efficiency.

QD enhanced applications are currently under development or are in limited production (QD-LED lighting). The end user markets for QDs are potentially very lucrative. Lighting and displays each represent $100 billion plus markets and will continue to grow. QD materials and component therefore are potentially a multi-billion sub-market revenue opportunity just for these sectors. Additional markets in solar, security, thermoelectrics and magnetics could double this potential market.

This 90 page report maps the current and future market for quantum dots and includes:

  • Market revenue estimates for quantum dots to 2024
  • End user markets
  • Company profiles

MAIN MARKETS FOR QUANTUM DOTS

  • Displays – Market drivers, trends, suppliers and products
  • Energy (Photovoltaics and Solid-State Lighting) – Market drivers, trends, suppliers and products
  • Biomedicine – Market drivers, trends, suppliers and products
  • Security – Market drivers, trends, suppliers and products
  • Sensors – Market drivers, trends, suppliers and products

Companies Mentioned

  • American Dye Source
  • American Elements
  • Bayer MaterialScience AG
  • Cyrium Technologies
  • EBioscience
  • Emfutur Technologies
  • Evident Technologies
  • Genefinity S.r.l.
  • Invisage
  • Life Technologies Corporation
  • LG Display Co., Ltd.
  • Nanoco Technologies
  • Nano Axis LLC
  • Nano Optical Materials
  • NanoPhotonica
  • Nanoshel
  • Nanosquare, Inc.
  • Nanosys, Inc.
  • Ocean Nanotech LLC
  • PlasmaChem GmbH
  • QD Laser, Inc.
  • QLight Nanotech
  • QD Solution
  • QD Vision
  • Revolution Lighting Technologies
  • Samsung
  • Sigma-Aldrich
  • Selah Technologies, LLC
  • Solexant Technologies, LLC
  • Voxtel, Inc.

Genesis Nanotechnology Business Summary Chart

GNT Bussiness Summary Chart II

A Fresh Approach to the Business of Tech Transfer


 

Irish Times imageA new tech transfer body, KTI, will use novel ideas for exploiting research, says its head, Dr. Alison Campbell

A fresh approach to the commercialisation of research may be on the way following the recent launch of tech transfer body Knowledge Transfer Ireland.

Its head, Dr Alison Campbell, says she wants to try novel approaches to the business of exploiting research, including “easy IP”, in which a company might gain access to a licence for next to nothing with no strings attached. Impossible, you might say, and yet it makes sense here where a company might have to continue with its own research effort before managing to make a research discovery pay its way.

Irish Times image

Dr. Alison Campbell: “Engaging with the business community means you have a greater chance to see your research having a broader impact.”

Campbell has a clear view of what she wants to achieve in the coming years, and it is not all about fast bucks.

“We have to get away from looking only at the money because it is not just about that. This is about economic development and societal benefit. If we want to benefit the economy then we are not going to do the big fat licensing deals,” she says.

The new tech transfer office, KTI, is hosted by Enterprise Ireland, but is not wholly new given its previous incarnation as the Central Technology Transfer Office.

KTI is run as a joint operation by Enterprise Ireland and the Irish Universities Association and promises to open up a two-way street between business and academia. It will encourage companies to avail of higher education institution expertise, or to become purchasers of licences and technologies from their discoverers. It promises to be a one-stop shop for companies looking to buy into useful research findings, but; however, similar claims were made over the years by earlier efforts at streamlining this problematic area.

Secret ingredient Previous attempts to kick-start Ireland’s knowledge transfer have delivered only limited results, but this one promises to be different due to its secret ingredient: Campbell herself. She was hired by the IUA last July as its director of tech transfer and then took over as the head of the joint Enterprise Ireland/Irish Universities Association office. She has an extremely useful mix of experience and expertise that should serve very well as KTI gets underway.

One of the new approaches Campbell wants to try is easy IP, in which you might give a technology licence away for very little but with certain minor conditions. If the company can’t make proper use of the licence it has to return it so someone else can have a go. But if there is some success with it then the company has to let the higher education institution that made the original discovery know their original ideas worked.

There is a payback even though it won’t all be about money, she believes. “The IP becomes a tool to create relationships.” Adding in a “bonanza clause” to seek a payback if the IP becomes a blockbuster breakthrough is just another IP licence, she argues. “You have to be brave enough to go with it.”

Campbell has a PhD in biochemistry, specialising in protein engineering and conducted research within higher education but also in the biotech industry as a lab staffer, so she knows research from both camps. She enjoyed the contrast between the two and what could be achieved. “I began to get interested in commercialisation and the interaction between industry and academia,” she says.

She next joined a funder, the UK’s Medical Research Council, working in its tech transfer operation at a time in the 1990s when the whole business of commercialising the results of publicly funded research was really getting traction. “We became a wholly owned subsidiary of the MRC as MRC Technology and we began to concentrate on the transfer of applied research.”

 

Make connections The main thrust of her approach is quite simple: to get the business community and academics talking. “We want Irish companies to engage with the research community where appropriate and to make connections with experts that exist within the research organisations. There is knowledge in there that might help them.”

But there also have to be benefits for the researchers. “Engaging with the business community means you have a greater chance to see your research having a broader impact. Academics don’t do research in a vacuum – they want to see some benefit coming from it.

“Involvement with companies should also allow them to bring back insights, for example, knowledge of how a company works. The institutions that will be really successful in this are the ones where the heads see this as strategically important.”

She will not be drawn into the old argument about funding for applied versus basic research. “It is all about the knowledge so let’s get the knowledge out.” One way or the other, ultimately it will be about the researchers, she believes.

“You can build a technology transfer team but actually it is the researchers who will deliver this agenda.”

The KTI will be assessed on a number of metrics but Campbell has a clear idea of what success will look like.

“At the end of the day it will be when the business community become advocates for the KTI system,” she says.

Sharp Demonstrates Ultra-Efficient Solar Cells: New Technology Could Be Twice as Efficient at Converting Sunlight to Electricity.


3adb215 D BurrisNew technology could be twice as efficient at converting sunlight to electricity.

The best solar cells convert less than one-third of the energy in sunlight into electricity, although for decades researchers have calculated that exotic physics could allow them to convert far more. Now researchers at Sharp have built a prototype that demonstrates one of these ideas. If it can be commercialized, it would double the amount of power a solar cell can generate, offering a way to make solar power far more economical.

The researchers figured out a way around a bothersome phenomenon: when sunlight strikes a solar cell, it produces some very high-energy electrons, but within a few trillionths of a second, those electrons shed most of their energy as waste heat.

The Sharp team found a way to extract these electrons before they give up that energy, thereby increasing the voltage output of their prototype solar cell. It’s far from a practical device—it’s too thin to absorb much sunlight, and for now it works only with a single wavelength of light—but it’s the first time that anyone has been able to generate electrical current using these high-energy electrons. In theory, solar cells that exploit this technique could reach efficiencies over 60 percent.

The approach is one of several that could someday break open the solar industry and make fossil fuels expensive in comparison. High-efficiency solar cells would lower the cost of installation, which today is often more expensive than the cells themselves.

Exploiting exotic physics requires both understanding the behavior of certain materials and figuring out how to make them with high precision (see “Capturing More Light with a Single Solar Cell” and “Nanocharging Solar”). The Sharp device relies on the ability to make high-quality, nanometers-thick layers of semiconducting materials (such as gallium arsenide), which create a shortcut for high-energy electrons to move out of the solar cell.

Another way to achieve ultra-high efficiencies now is by stacking up different kinds of solar cells (see “Exotic, Highly Efficient Solar Cells May Soon Get Cheaper”), but doing so is very expensive. Meanwhile, MIT researchers are studying the transient behavior of electrons in organic materials to find inexpensive ways to make ultra-efficient solar cells.

Each of the alternative approaches is at an early stage. James Dimmock, the senior researchers who developed the new device at Sharp, says he expects that his technique will initially be used to help boost the efficiency of conventional devices, not to create new ones.

 

FROM THE ARCHIVES ALSO SEE:

“Nanocharging Solar”

Arthur Nozik believes quantum-dot solar power could boost output in cheap photovoltaics.

Arthur Nozik hopes quantum dots will enable the production of more efficient and less expensive solar cells, finally making solar power competitive with other sources of electricity

 

 

 

 

No renewable power source has as much theoretical potential as solar energy. But the promise of cheap and abundant solar power remains unmet, largely because today’s solar cells are so costly to make.

Photovoltaic cells use semiconductors to convert light energy into electrical current. The workhorse photo­voltaic material, silicon, performs this conversion fairly efficiently, but silicon cells are relatively expensive to manufacture. Some other semiconductors, which can be deposited as thin films, have reached market, but although they’re cheaper, their efficiency doesn’t compare to that of silicon. A new solution may be in the offing: some chemists think that quantum dots–tiny crystals of semi­conductors just a few nanometers wide–could at last make solar power cost-competitive with electricity from fossil fuels.
By dint of their size, quantum dots have unique abilities to interact with light. In silicon, one photon of light frees one electron from its atomic orbit. In the late 1990s, Arthur Nozik, a senior research fellow at the National Renewable Energy Laboratory in Golden, CO, postulated that quantum dots of certain semiconductor materials­ could release two or more electrons when struck by high-energy photons, such as those found toward the blue and ultraviolet end of the spectrum.

In 2004, Victor Klimov of Los Alamos­ National Laboratory in New Mexico provided the first experimental proof that Nozik was right; last year he showed that quantum dots of lead selenide could produce up to seven electrons per photon when exposed to high-energy ultraviolet light. Nozik’s team soon demonstrated the effect in dots made of other semiconductors, such as lead sulfide and lead telluride.

These experiments have not yet produced a material suitable for commercialization, but they do suggest that quantum dots could someday increase the efficiency of converting sunlight into electricity. And since quantum dots can be made using simple chemical reactions, they could also make solar cells far less expensive. Researchers in Nozik’s lab, whose results have not been published, recently demonstrated the extra-electron effect in quantum dots made of silicon; these dots would be far less costly to incorporate into solar cells than the large crystalline sheets of silicon used today.

To date, the extra-electron effect has been seen only in isolated quantum dots; it was not evident in the first proto­type photovoltaic devices to use the dots. The trouble is that in a working solar cell, electrons must travel out of the semiconductor and into an external electrical circuit. Some of the electrons freed in any photovoltaic cell are inevitably “lost,” recaptured by positive “holes” in the semiconductor. In quantum dots, this recapture happens far faster than it does in larger pieces of a semiconductor; many of the freed electrons are immediately swallowed up.

The Nozik team’s best quantum­-dot solar cells have managed only about 2 percent efficiency, far less than is needed for a practical device. However, the group hopes to boost the efficiency by modifying the surfaces of the quantum dots or improving electron transport between dots.

The project is a gamble, and Nozik readily admits that it might not pay off. Still, the enormous potential of the nanocrystals keeps him going. Nozik calculates that a photovoltaic device based on quantum dots could have a maximum efficiency of 42 percent, far better than silicon’s maximum efficiency of 31 percent. The quantum dots themselves would be cheap to manufacture, and they could do their work in combination with materials like conducting polymers that could also be produced inexpensively. A working quantum dot-polymer cell could eventually place solar electricity on a nearly even economic footing with electricity from coal. “If you could [do this], you would be in Stockholm–it would be revolutionary,” says Nozik.

A commercial quantum-dot solar cell is many years away, assuming it’s even possible. But if it is, it could help put our fossil-fuel days behind us.

*** Article is Archives March 2007 ***

 

Quantum Dot Solar Cells Boost Significant Efficiency Gains


Los Alamos Solar 49686Abstract:
Los Alamos researchers have demonstrated an almost four-fold boost of the carrier multiplication yield with nanoengineered quantum dots. Carrier multiplication is when a single photon can excite multiple electrons. Quantum dots are novel nanostructures that can become the basis of the next generation of solar cells, capable of squeezing additional electricity out of the extra energy of blue and ultraviolet photons.

New Los Alamos Approach May Be Key to Quantum Dot Solar Cells With Real Gains in Efficiency: Nanoengineering Boosts Carrier Multiplication in Quantum Dots

Los Alamos, NM | Posted on June 19th, 2014

“Typical solar cells absorb a wide portion of the solar spectrum, but because of the rapid cooling of energetic (or ‘hot’) charge carriers, the extra energy of blue and ultraviolet solar photons is wasted in producing heat,” said Victor Klimov, director of the Center for Advanced Solar Photophysics (CASP) at Los Alamos National Laboratory.

Getting two for the price of one

“In principle, this lost energy can be recovered by converting it into additional photocurrent via carrier multiplication. In that case, collision of a hot carrier with a valence-band electron excites it across the energy gap,” Klimov said. “In this way, absorption of a single photon from the high-energy end of the solar spectrum produces not just one but two electron-hole pairs, which in terms of power output means getting two for the price of one.”

Los Alamos Solar 49686Core/shell PbSe/CdSe quantum dots (a) and a carrier multiplication (CM) pathway (b) in these nano structures. (a) Transmission electron microscopy image of thick-shell PbSe/CdSe quantum dots developed for this study. (b) A hot hole generated in the shell via absorption of a photon collides with a core-localized valence-band electron, promoting it across the energy-gap, which generates a second electron-hole pair. In thick-shell PbSe/CdSe quantum dots this process is enhanced due to slow relaxation of shell-localized holes into the core.

Carrier multiplication is inefficient in the bulk solids used in ordinary solar cells but is appreciably enhanced in ultrasmall semiconductor particles – also called quantum dots — as was first demonstrated by LANL researchers in 2004 (Schaller & Klimov, Phys. Rev. Lett. 92, 186601, 2004). In conventional quantum dots, however, carrier multiplication is not efficient enough to boost the power output of practical devices.

A new study conducted within the Center for Advanced Solar Photophysics demonstrates that appropriately engineered core/shell nanostructures made of lead selenide and cadmium selenide (PbSe and CdSe) can increase the carrier multiplication yield four-fold over simple PbSe quantum dots.

Klimov explained, “This strong enhancement is derived primarily from the unusually slow phonon relaxation of hot holes that become trapped in high-energy states within the thick CdSe shell. The long lifetime of these energetic holes facilitates an alternative relaxation mechanism via collisions with core-localized valence band electron which leads to highly efficient carrier multiplication.”

The nuts and bolts of slowing cooling

To realize the effect of slowed carrier cooling LANL researchers have fabricated PbSe quantum dots with an especially thick CdSe shell. Qianglu Lin, a CASP student working on the synthesis of these materials said, “A striking feature of the thick-shell PbSe/CdSe quantum dots is fairly bright visible emission, from the shell, observed simultaneously with the infrared emission from the core. This shows that intraband cooling is slowed down dramatically, so that holes reside in the shell long enough to produce emission.”

“This slowed relaxation, which underlies the observed enhancement of carrier multiplication, likely relates to the interplay between core- versus shell-localization of valence-band states” explained Nikolay Makarov, a spectroscopist working on this project. Istvan Robel, another CASP member added “Our modeling indicates that when the shell is thick enough, the higher-energy hole states lay primarily in the shell, while lower-energy states still remain confined to the core. This separation leads to electronic decoupling of higher- from lower-energy holes states, which is responsible for the observed slowed cooling.”

What this could mean in future

While the present CASP work is based on PbSe/CdSe quantum dots, the concept of “carrier-multiplication engineering” through control of intraband cooling is general, and should be realizable with other combinations of materials and/or nanostructure geometries.

Jeff Pietryga, lead CASP chemist says, “Further enhancement in carrier multiplication should be possible by combining this new approach with other demonstrated means for increasing multicarrier yields, such as by using shape-control (as in nanorods) and/or materials in which cooling is already naturally slower, like PbTe.” Applied together, these strategies might provide a practical route to nanostructures exhibiting carrier multiplication performance approaching the limits imposed by energy conservation.

Funding: The Center for Advanced Solar Photophysics (CASP) is an Energy Frontier Research Center funded by the Office of Science of the US Department of Energy.

About Los Alamos National Laboratory

Los Alamos National Laboratory, a multidisciplinary research institution engaged in strategic science on behalf of national security, is operated by Los Alamos National Security, LLC, a team composed of Bechtel National, the University of California, The Babcock & Wilcox Company, and URS Corporation for the Department of Energy’s National Nuclear Security Administration.

Los Alamos enhances national security by ensuring the safety and reliability of the U.S. nuclear stockpile, developing technologies to reduce threats from weapons of mass destruction, and solving problems related to energy, environment, infrastructure, health, and global security concerns.

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One-Step to Solar-Cell Efficiency?


QDOT images 6Rice University scientists have created a one-step process for producing highly efficient materials that let the maximum amount of sunlight reach a solar cell.
The Rice lab of chemist Andrew Barron found a simple way to etch nanoscale spikes into silicon that allows more than 99 percent of sunlight to reach the cells’ active elements, where it can be turned into electricity.
The research by Barron and Rice graduate student and lead author Yen-Tien Lu appears in the Royal Society of Chemistry’s Journal of Materials Chemistry A (“Anti-reflection layers fabricated by a one-step copper-assisted chemical etching with inverted pyramidal structures intermediate between texturing and nanopore-type black silicon”).

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A cross section shows inverted pyramids etched into silicon by a chemical mixture over eight hours. (Image: Barron Group/Rice University)
The more light absorbed by a solar panel’s active elements, the more power it will produce. But the light has to get there. Coatings in current use that protect the active elements let most light pass but reflect some as well. Various strategies have cut reflectance down to about 6 percent, Barron said, but the anti-reflection is limited to a specific range of light, incident angle and wavelength.
Enter black silicon, so named because it reflects almost no light. Black silicon is simply silicon with a highly textured surface of nanoscale spikes or pores that are smaller than the wavelength of light. The texture allows the efficient collection of light from any angle — from sunrise to sunset.
Barron and Lu have replaced a two-step process that involved metal deposition and electroless chemical etching with a single step that works at room temperature.
The chemical stew that makes it possible is a mix of copper nitrate, phosphorous acid, hydrogen fluoride and water. When applied to a silicon wafer, the phosphorous acid reduces the copper ions to copper nanoparticles. The nanoparticles attract electrons from the silicon wafer’s surface, oxidizing it and allowing hydrogen fluoride to burn inverted pyramid-shaped nanopores into the silicon.
Fine-tuning the process resulted in a black silicon layer with pores as small as 590 nanometers (billionths of a meter) that let through more than 99 percent of light. (By comparison, a clean, un-etched silicon wafer reflects nearly 100 percent of light.)
Barron said the spikes would still require a coating to protect them from the elements, and his lab is working on ways to shorten the eight-hour process needed to perform the etching in the lab. But the ease of creating black silicon in one step makes it far more practical than previous methods, he said.
Source: Rice University

Quantum Materials Ships 20 Grams of Quantum Dots to Major Asia-Based Global Company in First Weeks of Operation of Scaled Production System


atomsinananoSAN MARCOS, Texas, June 19, 2014 Quantum Materials Corporation(OTCQB:QTMM) today announced the shipment of 20 grams of quantum dots to a major Asia-based global company.

 

Quantum Materials accomplished the manufacture in a portion of the first week after installation and commissioning runs of the Company’s new automated production system.  The precision afforded by automating production allows Quantum Materials to produce high performance tetrapod quantum dots and other materials with exacting quality control resulting in uniform structure, and tuned narrow emission FWHM.

Quantum Materials Vice President of Research & Development David Doderer said, “We are confident that our first week’s output paves the way for our successful participation in the quantum dot-enabled market.  While the breadth of possibilities of making different highly functional quantum dots and nanomaterials with specific and custom selectivity of performance characteristics give us much to explore, we have proven the capability of mass production of bespoke products to meet specific consumer product and research market demands.”

This custom delivery is the first of several that Quantum Materials has slated to be produced and shipped to potential partners and clients as requested for varied applications in the optoelectronic, photovoltaic and nanobiology fields.

In optoelectronics, the uniformity of Quantum Materials quantum dots is intended to enhance color gamut and luminescence performance for targeted consumer electronics products. In photovoltaics, longer tetrapod arms exhibit higher conversion of photons for sensors and solar cells, and in nanobio, QMC quantum dots can be used for near-instantaneous, highly accurate results in diagnostic assays, medical imaging and as drug delivery platforms.