Solar-driven Hydrogen Economy

Hydrogen as a fuel source, rather than hydrocarbons like oil and coal, offers many benefits. Burning hydrogen produces harmless water with the potential to eliminate carbon dioxide emissions and their environmental burden. In pursuit of technologies that could lead to a breakthrough in achieving a hydrogen economy, a key issue is making hydrogen cheaply. Using catalysts to split water is the ideal way to generate hydrogen, but doing so usually requires an energy input from other chemicals, electricity, or a portion of sunlight which has high enough energy.

Now researchers at Osaka University have developed a new catalytic system for efficiently splitting water and making hydrogen with energy from normal sunlight. Their study was recently reported in Angewandte Chemie International Edition.

It has not been possible to use visible light for photocatalysis, but our approach of combining nanostructured black phosphorus for water reduction to hydrogen and bismuth vanadate for water oxidation to oxygen lets us make use of a wide range of the solar spectrum to make hydrogen and oxygen with unprecedented efficiency,” lead author Mingshan Zhu says.

Black phosphorus has a flat, two-dimensional structure similar to that of graphene and strongly absorbs light across the whole of the visible spectrum. The researchers combined the black phosphorus with bismuth vanadate, which is a well-known water oxidation catalyst.

In the same way that plants shuttle electrons between different structures in natural photosynthesis to split water and make oxygen, the two components of this new catalyst could rapidly transfer electrons excited by sunlight. The amounts of the two components was also optimized in the catalyst, leading to production of hydrogen and oxygen gases in an ideal 2:1 ratio.


Paracetamol On Mars

How to produce medicine sustainably and cheaply, anywhere you want, whether in the middle of the jungle or even on Mars? Looking for a ‘mini-factory’ whereby sunlight can be captured to make chemical products? Inspired by the art of nature where leaves are able to collect enough sunlight to produce food, chemical engineers at Eindhoven University of Technology (TU/e) in Netherlands have presented such a scenario. 
Using sunlight to make chemical products has long been a dream of many a chemical engineer. The problem is that the available sunlight generates too little energy to kick off reactions. However, nature is able to do this. Antenna molecules in leaves capture energy from sunlight and collect it in the reaction centers of the leaf where enough solar energy is present for the chemical reactions that give the plant its food (photosynthesis).

Luminescent Solar Concentrator-based Photomicroreactor (LSC-PM, artificial leaf for organic synthesis), research by PhD Dario Cambie & Timothy Noël, group Micro Flow Chemistry and Process Technology, Chemical Engineering and Chemistry, TU Eindhoven. photo: TU/e, Bart van Overbeeke

Luminescent Solar Concentrator-based Photomicroreactor (LSC-PM, artificial leaf for organic synthesis), research by PhD Dario Cambie & Timothy Noël

The researchers came across relatively new materials, known as luminescent solar concentrators (LSC’s), which are able to capture sunlight in a similar way. Special light-sensitive molecules in these materials capture a large amount of the incoming light that they then convert into a specific color that is conducted to the edges via light conductivity. These LSC’s are often used in practice in combination with solar cells to boost the yield.


The results surpassed all their expectations, and not only in the lab. “Even an experiment on a cloudy day demonstrated that the chemical production was 40 percent higher than in a similar experiment without LSC material”, says research leader Noël. “We still see plenty of possibilities for improvement. We now have a powerful tool at our disposal that enables the sustainable, sunlight-based production of valuable chemical products like drugs or crop protection agents.”

For the production of drugs there is certainly a lot of potential. The chemical reactions for producing drugs currently require toxic chemicals and a lot of energy in the form of fossil fuels. By using visible light the same reactions become sustainable, cheap and, in theory, countless times faster. But Noël believes it should not have to stop there. “Using a reactor like this means you can make drugs anywhere, in principle, whether malaria drugs in the jungle or paracetamol on Mars. All you need is sunlight and this mini-factory.

The findings are described in the journal Angewandte Chemie.


Artificial Skin Breathes like Human Skin

A scientist in Chile is using microscopic algae to make skingreen skin. These very small, very simple plants are being used to develop a new artificial skin for humans. The problem with most current artificial skin is that there are no blood vessels – so the man-made skin cannot produce the oxygen it needs to live. But with algae, the skin can breathe through the process of photosynthesis.

artificial-skin-breathesCLICK ON THE IMAGE TO ENJOY THE VIDEO

What we’re basically doing is incorporating micro-algae, which are like microscopic plants into different types of materials. For example, when we apply artificial skin what we have is the characteristics of plants which means when it is lit up it can produce oxygen,” says Tomas Egana from the Chile’s Catholic University, professor at the Institute of biological engineering. And the benefits of the algae could go beyond just a cosmetic improvement. It may help human skin heal itself: “These micro-algae can be genetically modified. So that in addition to producing oxygen they will produce different factors, for example antibiotics, anti-inflammatories and pro-regenerative molecules. So, we are going to have material which is completely artificial and still, which is a structure that has material that is alive.

Professor Egana says the green-colored skin could eventually be used to help patients treat open wounds, tumors and possibly avoid amputations. But patients need not worry about looking like the Incredible Hulk. Egana believes the green color will fade over time as the algae dies. At the moment, animal testing has proven a success. Human trials are expected next year.


Dye Solar Cells Make Your Mouse Battery Obsolete

These little glass squares could just be the answer to charging all your electronics. The glass-printed photovoltaic cells are a form of Dye Solar Cell technology created by Israeli company 3G Solar Photovoltaics. They’re so sensitive they can generate power from indirect, indoor lighting. Check it out. The company’s head of R&D Nir Stein is taking the batteries out of this mouse, which has the company’s dye solar cell module installed on top.

solar cells powered mouseCLICK ON THE IMAGE TO ENJOY THE VIDEO

What you see here is a computer mouse that has a bluetooth connectivity inside it and is powered by 3G solar photovoltaic cells. So when you have thousands of sensors, for instance in a building, which is going to happen in the next few years, you’ll never have to change a battery again,” says Nir Stein.
Dye-sensitized solar cells, or Graetzel cells, were discovered about 20 years ago. When they’re exposed to sunlight the dye becomes excited and creates an electronic charge without the need for pricey semiconductors. Kind of like the way plants use chlorophyll to turn sunlight into energy through photosynthesis. While the technology is the same, 3G Solar Voltaics‘ CEO Barry Breen says that being able to embed the cells on small surfaces has the potential to change the way we charge everyday devices. ) BARRY N. BREEN, CEO OF 3GSOLAR PHOTOVOLTAICS, SAYING: “What we offer in our cells, in our light power devices, is a solution that gives three times the power of anything else that exists, and we’re talking indoors, where most the electronics are used. So three times the power to run these new electronics, the new sensors, the smart watches and other wearables. So it’s a way to keep those powered that couldn’t be done before,” comments Barry Breen, CEO of 3G Solar Photovoltaics.

The small modules are durable and last for about 10 years. They can be colored and fitted to the shape of a device so they don’t stand out. Although still a prototype, the makers say the technology could make batteries a thing of the past.



Powered by plants your phone is charged in 2 hours

It’s a common problem across the world. Too many smartphones and not enough electrical sockets to charge them. But thanks to three engineering students from Chile, charging your device may soon be as easy as plugging it into your favorite household plant. The idea sprouted back in 2009 during a chaotic exam week. Desperate to charge their devices, the students stepped outside to the school garden to catch a breath of fresh air and quell their frustrations. That’s when they realized that the plants producing the oxygen they were breathing also produce energy.

biocircuit_buried_in_the_soilCLICK ON THE IMAGE TO ENJOY THE VIDEO
After that, we thought, why don’t they have a socket? Because there are so many plants and living things which have the potential to produce energy, why not?” asks Evelyn Aravena,  electrical engineering and industrial automation student at  Duoc Institute in Valparaiso (Chile).

The trio began prototyping a device they call E-Kaia. It’s a biocircuit buried in the soil that harnesses energy produced by plants during photosynthesis and converts it into electricity. The team explains that the device feeds off the natural energy cycle of a plant.  “There is a complete cycle of the plant and when making this cycle, we decided to incorporate into it, then we would not affect the plant’s growth. And the biocircuit makes an acquisition and transforms it into energy to later make charges of low consumption“, adds Camila Rupchich, also student at Duoc Insitute.

The device can fully charge a smartphone in under two hours. The team is currently fine tuning the biocircuit with the hopes of launching it commercially in late 2016.

Integrated Solar Fuels Generator

Generating and storing renewable energy, such as solar or wind power, is a key barrier to a clean-energy economy. When the Joint Center for Artificial Photosynthesis (JCAP) was established at Caltech (California Institute of Technology) and its partnering institutions in 2010, the U.S. Department of Energy (DOE) Energy Innovation Hub had one main goal: a cost-effective method of producing fuels using only sunlight, water, and carbon dioxide, mimicking the natural process of photosynthesis in plants and storing energy in the form of chemical fuels for use on demand. Over the past five years, researchers at JCAP have made major advances toward this goal, and they now report the development of the first complete, efficient, safe, integrated solar-driven system for splitting water to create hydrogen fuels.


This result was a stretch project milestone for the entire five years of JCAP as a whole, and not only have we achieved this goal, we also achieved it on time and on budget,” says Caltech’s Nate Lewis, professor of chemistry, and the JCAP scientific director.

This accomplishment drew on the knowledge, insights and capabilities of JCAP, which illustrates what can be achieved in a Hub-scale effort by an integrated team,” adds Harry Atwater, director of JCAP. “The device reported here grew out of a multi-year, large-scale effort to define the design and materials components needed for an integrated solar fuels generator.
Another key advance is the use of active, inexpensive catalysts for fuel production. The photoanode requires a catalyst to drive the essential water-splitting reaction. Rare and expensive metals such as platinum can serve as effective catalysts, but in its work the team discovered that it could create a much cheaper, active catalyst by adding a 2-nanometer-thick layer of nickel. This catalyst is among the most active known catalysts for splitting water molecules into oxygen, protons, and electrons and is a key to the high efficiency displayed by the device. The demonstration system is approximately one square centimeter in area, converts 10 percent of the energy in sunlight into stored energy in the chemical fuel, and can operate for more than 40 hours continuously. “This new system shatters all of the combined safety, performance, and stability records for artificial leaf technology by factors of 5 to 10 or more ,” Lewis says. “Our work shows that it is indeed possible to produce fuels from sunlight safely and efficiently in an integrated system with inexpensive components,” Lewis adds .


Bionic Particles To Turn Sunlight Into Fuel

Inspired by fictional cyborgs like Terminator, a team of researchers at the University of Michigan and the University of Pittsburgh has made the first bionic particles from semiconductors and proteins. These particles recreate the heart of the process that allows plants to turn sunlight into fuel.

Human endeavors to transform the energy of sunlight into biofuels using either artificial materials or whole organisms have low efficiency,” said Nicholas Kotov, the Florence B. Cejka Professor of Engineering at the University of Michigan, who led the experiment. A bionic approach could change that. The bionic particles blend the strengths of inorganic materials, which can readily convert light energy to electron energy, with biological molecules whose chemical functions have been highly developed through evolution. The team first designed the particles to combine cadmium telluride, a semiconductor commonly used in solar cells, with cytochrome C, a protein used by plants to transport electrons in photosynthesis. With this combination, the semiconductor can turn a ray from the sun into an electron, and the cytochrome C can pull that electron away for use in chemical reactions that could clean up pollution or produce fuel, for instance. U-M‘s Sharon Glotzer, the Stuart W. Churchill Professor of Chemical Engineering, who led the simulations, compares the self-assembly to the way that the surfaces of living cells form, using attractive forces that are strong at small scales but weaken as the structure grows. Kotov’s group confirmed that the semiconductor particles and proteins naturally assemble into larger particles, roughly 100 nanometers (0.0001 millimeters) in diameter.

We merged biological and inorganic in a way that leverages the attributes of both to get something better than either alone,” Glotzer said. Powered by electrons from the cytochrome C, the enzyme could remove oxygen from nitrate molecules. Like the structures that accomplish photosynthesis in plants, the bionic particles took a beating from handling the energy. Nature constantly renews these working parts in plants, and through self-assembly, the particles may also be able to renew themselves.

Keeping Sun Energy For Use At Night

Solar energy has long been used as a clean alternative to fossil fuels such as coal and oil, but it could only be harnessed during the day when the sun’s rays were strongest. Now researchers led by Tom Meyer at the Energy Frontier Research Center at the University of North Carolina (UNC) at Chapel Hill have built a system that converts the sun’s energy not into electricity but hydrogen fuel and stores it for later use, allowing us to power our devices long after the sun goes down.

photoelectrosynthesis cell generates hydrogenThe system generates hydrogen fuel by using sun energy to split water in its component parts. After the split the hydrogen is stored, while the byproduct, oxygen, is released in the air

So called ‘solar fuels’ like hydrogen offer a solution to how to store energy for nighttime use by taking a cue from natural photosynthesis,” said Meyer, Arey Distinguished Professor of Chemistry at UNC’s College of Arts and Sciences. “Our new findings may provide a last major piece of a puzzle for a new way to store the sun’s energy – it could be a tipping point for a solar energy future.”


Electric Power From Plants

Barry D. Bruce, professor of biochemistry, cellular and molecular biology, at the University of Tennessee, Knoxville,  and a team of researchers have developed a system that taps into photosynthetic processes to produce efficient and inexpensive energy.

“Because the system is so cheap and simple, my hope is that this system will develop with additional improvements to lead to a green, sustainable energy source,” said Bruce, noting that today’s fossil fuels were once, millions of years ago, energy-rich plant matter whose growth also was supported by the sun via the process of photosynthesisThis system is a preferred method of sustainable energy because it is clean and it is potentially very efficient, he added. As opposed to conventional photovoltaic solar power systems, we are using renewable biological materials rather than toxic chemicals to generate energy. Likewise, our system will require less time, land, water and input of fossil fuels to produce energy than most biofuels.

Bruce collaborated with researchers from the Massachusetts Institute of Technology and Ecole Polytechnique Federale in Switzerland to develop a process that improves the efficiency of generating electric power using molecular structures extracted from plants. Their findings are in the current issue of Nature: Scientific Reports.