Posts belonging to Category green power

Water-powered MotorBike

Ricardo Azevedo was frustrated with the ever increasing price of gas. So he used his skills as a mechanic and took some tips from his son’s chemistry book to build a water powered motorcycle.

hydrogen motobike

I still haven’t developed everything is it capable of, but I did some tests and in certain settings it can go 500 kilometres (310 miles) using one litre of water,” says Azevedo.
An electrical current is fed into a canister of water which breaks the liquid down into hydrogen and oxygen using the process of electrolysis. The hydrogen gas is then used to power the engine. Research into hydrogen combustion power has increased dramatically over the past decade and while the chemical process used to generate energy from water is well understood, its market potential is curbed until a way to safely contain and use the highly flammable hydrogen gas is developed. Azevedo says the environmental benefits of using his water powered bike or other hydrogen energy sources far outweigh the risks involved.  “It does not cause any damage to the environment, on the contrary as it will go on to replace fossil fuels and reduce carbon monoxide emissions,” he adds.
Azevedo is continuing to tinker and improve the efficiency of his bike. He says getting fuel from a river beats stopping at a gas station any day of the week.


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 .


Biodegradable Nanoparticles For Harmless Pesticides

In this lab at North Carolina State University the future of keeping crops free of harmful bacteria is taking shape – albeit a very small shape. Researcher Alexander Richter is designing a new type of nanoparticle with lignin, an organic polymer found in almost all plants and trees, at its core. Currently, silver based nanoparticles are used in a wide range of pesticides to treat crops, but while silver has strong anti-microbial properties, its use is controversial.


Their post-application activity when released into the environment was actually seen as a potential concern by the U.S. Environmental Protection Agency. This is because the particles may stay active after the application, they may translocate after the application, they may kill good bacteria in the environment, which is undesired” says Alexander Tichter.

Dr. Orlin Velev, Professor of  chemical and biomolecular engineering adds: “So the problem is how do you potentially remove that danger from engineered nanomaterials?” The answer was to use less silver and replace the metallic core with lignin, making the newly engineered particles biodegradable but still an effective weapon in tackling dangerous bacteria like e-coli.
Our idea, or our approach, was to see if we can, if this is the problem, we replace the metallic core, which doesn’t participate in microbial action, with a biodegradable core. And by doing so, we could actually make the nanoparticles keep their functionality but make them degradable while also reducing the amount of the silver core in the nanoparticle system“, explains Richter.  And that equates to safer fruits and vegetables that are treated with less with chemicals as they grow.
“We believe that this can lead to a new generation of agricultural treatment products, that they’re going to be more efficient, that they’re going to use less chemicals, and that they’re going to be more friendly toward the environment” says Dr. Yelev.
The team has started a company to take their research to the next level with the hopes of perfecting the technology, scaling it up, and preparing it for commercialization.


How To Remove Greenhouse Gas From the Air

Finding a technology to shift carbon dioxide (CO2), the most abundant anthropogenic greenhouse gas, from a climate change problem to a valuable commodity has long been a dream of many scientists and government officials. Now, a team of chemists says they have developed a technology to economically convert atmospheric CO2 directly into highly valued carbon nanofibers for industrial and consumer products.

carbon nanofibers

We have found a way to use atmospheric CO2 to produce high-yield carbon nanofibers,” says Stuart Licht, Ph.D., who leads a research team at George Washington University. “Such nanofibers are used to make strong carbon composites, such as those used in the Boeing Dreamliner, as well as in high-end sports equipment, wind turbine blades and a host of other products.

Previously, the researchers had made fertilizer and cement without emitting CO2, which they reported. Now, the team, which includes postdoctoral fellow Jiawen Ren, Ph.D., and graduate student Jessica Stuart, says their research could shift COfrom a global-warming problem to a feed stock for the manufacture of in-demand carbon nanofibers.

Licht calls his approach “diamonds from the sky.” That refers to carbon being the material that diamonds are made of, and also hints at the high value of the products, such as the carbon nanofibers that can be made from atmospheric carbon and oxygen.

A press conference on this topic will be held Wednesday, Aug. 19, at 9:30 a.m. Eastern time in the Boston Convention & Exhibition Center. Reporters may check-in at Room 153B in person, or watch live on YouTube. To ask questions online, sign in with a Google account.

Solar Power: Nanorods-based Perovskite Module

Research teams from the Universiti Malaysia Pahang and University of Rome ‘Tor Vergata’, Italy, have jointly developed a nanorod-based perovskite solar module. The scientists claimed that it is the world’s first such solar module, as the perovskite solar modules are not only more efficient but also showed remarkable and improved shelf life.

perovskite solar panelThe nanostructuring of the photoelectrode, the researchers say, brings about great improvement in stability compared with those cells without a scaffold layer. The nanorod-based solar modules retained their original efficiency values even after 2,500 hours of shelf-life investigation.

At the same time, devices employing a conventional TiO2 nanoparticle material showed nearly 60 percent of original performance, and planar devices employing a compact TiO2 layer showed under 5 percent of original performance. The three types of electron transport layers were measured under similar experimental conditions.

The team have determined that the peculiar conformation of nanorods facilitated a stable perovskite phase due to their inherent stability and macroporous nature.

Rajan Jose, the team leader from University Malaysia Pahang is a professor of physics in the Faculty of Industrial Science & Technology and has been working on nanomaterials for energy applications since 2008. He calls the findings a significant milestone in the field of nanotechnology.

According to Rajan, his team has solved a technology bottleneck for large-scale application of the technology by applying “precise laser treatment and via interfacial engineering”.

The team has  published the findings in the  online edition of ACS Nano,  titled Vertical TiO2 Nanorods as a Medium for Stable and High-Efficiency Perovskite Solar Modules.



Electric Cars: How To Improve Batteries

One big problem faced by electrodes in rechargeable batteries, as they go through repeated cycles of charging and discharging, is that they must expand and shrink during each cycle — sometimes doubling in volume, and then shrinking back. This can lead to repeated shedding and reformation of its “skin” layer that consumes lithium irreversibly, degrading the battery’s performance over time.

Image with 2014 Renault

Image with 2014 Renault

Now a team of researchers at MIT and Tsinghua University in China has found a novel way around that problem: creating an electrode made of nanoparticles with a solid shell, and a “yolk” inside that can change size again and again without affecting the shell. The innovation could drastically improve cycle life, the team says, and provide a dramatic boost in the battery’s capacity and power.

The new findings, which use aluminum as the key material for the lithium-ion battery’s negative electrode, or anode, are reported in the journal Nature Communications, in a paper by MIT professor Ju Li and six others. The use of nanoparticles with an aluminum yolk and a titanium dioxide shell has proven to be “the high-rate champion among high-capacity anodes,” the team reports.


How To Measure Nanoparticles In Cosmetics

Cosmetics increasingly contain nanoparticles. One especially sensitive issue is the use of the miniscule particles in cosmetics, since the consumer comes into direct contact with the products. Sunscreen lotions for example have nanoparticles of titanium oxide. They provide UV protection: like a film made of infinite tiny mirrors, they are applied to the skin and reflect UV rays. But these tiny particles are controversial. They can penetrate the skin if there is an injury, and trigger an inflammatory reaction. Its use in spray-on sunscreens is also problematic. Scientists fear that the particles could have a detrimental effect on the lungs when inhaled. Even the effect on the environment has not yet been adequately researched. Studies indicate that the titanium oxide which has seeped into public beaches through sunscreens can endanger environmental balance. Therefore, a labeling requirement has been in force since July 2013, based on an EU Directive on cosmetics and body care products. If nano-sized ingredients are used in a product, the manufacturer must make this fact clear by adding “nano-” to the listed ingredient name. Due to requirements imposed by the legislature, the need for analysis methods is huge.


The light diffusion process and microscopy are not selective enough for a lot of studies, including toxicological examinations,” says Gabriele Beck-Schwadorf, scientist at the Fraunhofer Institute for Interfacial Engineering and Biotechnology IGB in Stuttgart (Germany). The group manager and her team have advanced and refined an existing measurement method in a way that allows them to determineResearchers measure individual particles by single particle, inductively coupled plasma mass spectrometry (or SP-ICP-MS). “With this method, I determine mass. Titanium has an atomic mass of 48 AMUs (atomic mass units). If I set the spectrometer to that, then I can target the measurement of titanium,” explains Katrin Sommer, food chemist at IGB.


Fuel Cell Electrodes 7 Times More Efficient

A new fabrication technique that produces platinum hollow nanocages with ultra-thin walls could dramatically reduce the amount of the costly metal needed to provide catalytic activity in such applications as fuel cells. The technique uses a solution-based method for producing atomic-scale layers of platinum to create hollow, porous structures that can generate catalytic activity both inside and outside the nanocages. The layers are grown on palladium nanocrystal templates, and then the palladium is etched away to leave behind nanocages approximately 20 nanometers in diameter, with between three and six atom-thin layers of platinum. Use of these nanocage structures in fuel cell electrodes could increase the utilization efficiency of the platinum by a factor of as much as seven, potentially changing the economic viability of the fuel cells.

A transmission electron microscope image shows a typical sample of platinum cubic nanocages

We can get the catalytic activity we need by using only a small fraction of the platinum that had been required before,” said Younan Xia, a professor in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University. Xia also holds joint faculty appointments in the School of Chemistry and Biochemistry and the School of Chemical and Biomolecular Engineering at Georgia Tech. “We have made hollow nanocages of platinum with walls as thin as a few atomic layers because we don’t want to waste any material in the bulk that does not contribute to the catalytic activity.
The research – which also involved researchers at the University of Wisconsin-Madison, Oak Ridge National Laboratory, Arizona State University and Xiamen University in China – was reported in the July 24 issue of the journal Science.


How To Make Solar Energy Conversion More Efficient

When it comes to installing solar cells, labor cost and the cost of the land to house them constitute the bulk of the expense.  The solar cells – made often of silicon or cadmium telluride – rarely cost more than 20 percent of the total costSolar energy could be made cheaper if less land had to be purchased to accommodate solar panels, best achieved if each solar cell could be coaxed to generate more power.

A huge gain in this direction has now been made by a team of chemists at the University of California, Riverside (UCR) that has found an ingenious way to make solar energy conversion more efficientThe researchers report in Nano Letters that by combining inorganic semiconductor nanocrystals with organic molecules, they have succeeded in “upconvertingphotons in the visible and near-infrared regions of the solar spectrum.


Solar-panels UCRChemists at the University of California, Riverside have found an ingenious way to make solar energy conversion more efficient

The infrared region of the solar spectrum passes right through the photovoltaic materials that make up today’s solar cells,” explained Christopher Bardeen, a professor of chemistry. The research was a collaborative effort between him and Ming Lee Tang, an assistant professor of chemistry. “This is energy lost, no matter how good your solar cell.  The hybrid material we have come up with first captures two infrared photons that would normally pass right through a solar cell without being converted to electricity, then adds their energies together to make one higher energy photon.  This upconverted photon is readily absorbed by photovoltaic cells, generating electricity from light that normally would be wasted.”


Solar Panels: Perovskites Better Than Silicon

In the solar power research community, a new class of materials called perovskites is causing quite a buzz, as scientists search for technology that has a better “energy payback time” than the silicon-based solar panels currently dominating the market. Now, a new study by scientists at Northwestern University and the U.S. Department of Energy’s Argonne National Laboratory reports that perovskite modules are better than any commercially available solar technology when products are compared on the basis of energy payback time.

Solar panels are an investment — not only in terms of money, but also energy. It takes energy to mine, process and purify raw materials, and then to manufacture and install the final product. Energy payback time considers the energy that went into creating the product and is a more comprehensive way to compare solar technology than conversion efficiency. The research team reports the energy payback time for solar panel technology made with perovskites could be as quick as two to three months, easily beating silicon-based panels, which typically need about two years to return the energy investment.

perovskite solar panel

People see 11 percent efficiency and assume it’s a better product than something that’s 9 percent efficient,” said Fengqi You, corresponding author on the study and assistant professor of chemical and biological engineering at Northwestern’s McCormick School of Engineering and Applied Science. “But that’s not necessarily true. One needs to take a broad perspective when evaluating solar technology.”

In what’s called a cradle-to-grave life cycle assessment, You and his colleagues traced a product from the mining of its raw materials until its retirement in a landfill. They determined the ecological impacts of making a solar panel and calculated how long it would take to recover the energy invested.

The findings have been published in the journal Energy & Environmental Science .


How To Clean Up Cigarette Smoke

The Korea Institute of Science and Technology (KIST) research team has developed a nano-catalyst for air cleaning in a smoking room that removes 100% of acetaldehyde, the first class carcinogen, which accounts for the largest portion of the gaseous substances present in cigarette smoke.

Air Cleaning DeviceFor the performance evaluation test, the research team made an air cleaning equipment prototype using the nano-catalyst filter. The equipment was installed in an actual smoking room in the size of 30 square meters (with processing capacity of 4 CMM). About 80% of cigarette smoke elements were processed and decomposed to water vapor and carbon dioxide, within 30 minutes, and 100% of them within 1 hour. The test condition is based on the processing capacity which could circulate the air inside the entire 30 square meter smoking room once every 15 mns.

The nano-catalyst filter uses a technology that decomposes elements of cigarette smoke using oxygen radical, which is generated by decomposing ozone in the air on the surface of the manganese-oxide-based nano-catalyst filter. An evaluation test with total volatile organic compounds (TVOC), such as acetaldehyde, nicotine and tar, which account for the largest volume of gaseous materials in cigarette smoke, is conducted to evaluate the performance of the newly-developed catalyst. The results show that the new catalyst decomposes over 98% of the aforementioned harmful substances.


Electric Planes Cross The Channel

Airbus Group  Friday completed its first-ever flight of an electric plane across the English Channel as the European plane maker seeks to spark interest in less polluting aircraft.

E fan

Airbus’s two-seat E-Fan demonstrator plane powered exclusively by lithium-batteries took 36 minutes to fly from Lydd in southern England to Calais, France, on the historic hop. It came soon after the single-seat Solar Impulse 2 flew from Japan to Hawaii in the longest-ever solar-powered flight as part of an around-the-world journey.

Just as cars are moving from burning fossil fuels to battery power, aircraft makers are exploring a similar shift to reduce carbon dioxide emissions. “It’s a big steppingstone,” said Jean Botti, chief technical officer at Airbus.

Private pilot Hugues Duval beat Airbus to the bragging rights of completing the first-ever Channel crossing in an electric plane when he traversed the body of water on Thursday in his single-seat Cri-Cri plane.

Airbus, better known for making airliners seating more than 100 passengers, plans to start delivering two-seat production versions of the E-Fan in 2017 through its VoltAir subsidiary.

A four-seat E-Fan 4.0 could follow 18 months later. It would introduce hybrid technology that could provide a springboard to building regional planes carrying 100 passengers, Mr. Botti said.