Posts belonging to Category green power

Could Nanotechnology End Hunger?

Each year, farmers around the globe apply more than 100 million tons of fertilizer to crops, along with more than 800,000 tons of glyphosate, the most commonly used agricultural chemical and the active ingredient in Monsanto’s herbicide Roundup. It’s a quick-and-dirty approach: Plants take up less than half the phosphorus in fertilizer, leaving the rest to flow into waterways, seeding algae blooms that can release toxins and suffocate fish. An estimated 90 percent of the pesticides used on crops dissipates into the air or leaches into groundwater.

child starving

With the global population on pace to swell to more than nine billion by 2050 amid the disruptions of climate change, scientists are racing to boost food production while minimizing collateral damage to the environment. To tackle this huge problem, they’re thinking small — very small, as in nanoparticles a fraction of the diameter of a human hair. Three of the most promising developments deploy nanoparticles that boost the ability of plants to absorb nutrients in the soil, nanocapsules that release a steady supply of pesticides and nanosensors that measure and adjust moisture levels in the soil via automated irrigation systems.

It’s all part of a rise in precision agriculture, which seeks a targeted approach to the use of fertilizer, water and other resources. Recognizing the potential impact of nanotechnology, the U.S. Department of Agriculture’s National Institute of Food and Agriculture (NIFA) beefed up funding between 2011 and 2015, from $10 million to $13.5 million. India, China and Brazil are also joining the latest green revolution. Scientists led by Pratim Biswas and Ramesh Raliya at Washington University in St. Louis have harnessed fungi to synthesize nanofertilizer. When sprayed on mung bean leaves, the zinc oxide nanoparticles increase the activity of three enzymes in the plant that convert phosphorus into a more readily absorbable form. Compared to untreated plants, nanofertilized mung beans absorbed nearly 11 percent more phosphorus and showed 27 percent more growth with a 6 percent increase in yield.

Raliya and his colleagues are also developing nanoparticles that enhance plants’ absorption of sunlight and investigating how nanofertilizers fortify crops with nutrients. In a study earlier this year, they found that zinc oxide and titanium dioxide nanoparticles increased levels of the antioxidant lycopene in tomatoes by up to 113 percent. Next, they want to design nanoparticles that enhance the protein content in peanuts. Along with mung beans, peanuts are a major source of protein in many developing countries.

Others are exploring nanoparticles that protect plants against insects, fungi and weeds. The Connecticut Agricultural Experiment Station and other institutions recently began field trials that use several types of metal oxide nanoparticles on tomato, eggplant, corn, squash and sorghum plants in areas infected with fungi known to threaten crops. Researchers led by Leonardo Fernandes Fraceto, of the Institute of Science and Technology, São Paulo State University, Campus Sorocaba, are designing slow-release nanocapsules that contain two types of fungicides or herbicides to reduce the likelihood of targeted fungi and weeds developing resistance. Scientists at the University of Tehran are conducting similar research. Still others are working on nanocapsules that release plant growth hormones. Existing technology could increase average yields up to threefold in many parts of Africa.

Solar Cells : How To Boost Efficiency Up To 30%

Researchers from the University of Houston have reported the first explanation for how a class of materials changes during production to more efficiently absorb light, a critical step toward the large-scale manufacture of better and less-expensive solar panels. The work, published this month as the cover story for Nanoscale, offers a mechanism study of how a perovskite thin film changes its microscopic structure upon gentle heating, said Yan Yao, assistant professor of electrical and computer engineering and lead author on the paper. This information is crucial for designing a manufacturing process that can consistently produce high-efficiency solar panels.

Perovskite cheap

Last year Yao and other researchers identified the crystal structure of the non-stoichiometric intermediate phase as the key element for high-efficiency perovskite solar cells. But what happened during the later thermal annealing step remained unclear. The work is fundamental science, Yao said, but critical for processing more efficient solar cells.

Otherwise, it’s like a black box,” he said. “We know certain processing conditions are important, but we don’t know why.”

The work also yielded a surprise: the materials showed a peak efficiency – the rate at which the material converted light to electricity – before the intermediate phase transformation was complete, suggesting a new way to produce the films to ensure maximum efficiency. Yao said researchers would have expected the highest efficiency to come after the material had been converted to 100 percent perovskite film. Instead, they discovered the best-performing solar devices were those for which conversion was stopped at 18 percent of the intermediate phase, before full conversion.

We found that the phase composition and morphology of solvent engineered perovskite films are strongly dependent on the processing conditions and can significantly influence photovoltaic performance,” the researchers wrote. “The strong dependence on processing conditions is attributed to the molecular exchange kinetics between organic halide molecules and DMSO (dimethyl sulfoxide) coordinated in the intermediate phase.

Perovskite compounds commonly are comprised of a hybrid organic-inorganic lead or tin halide-based material and have been pursued as potential materials for solar cells for several years. Yao said their advantages include the fact that the materials can work as very thin films – about 300 nanometers, compared with between 200 and 300 micrometers for silicon wafers, the most commonly used material for solar cells. Perovskite solar cells also can be produced by solution processing at temperatures below 150 degrees Centigrade (about 300 degrees Fahrenheit) making them relatively inexpensive to produce.

At their best, perovskite solar cells have an efficiency rate of about 22 percent, slightly lower than that of silicon (25 percent). But the cost of silicon solar cells is also dropping dramatically, and perovskite cells are unstable in air, quickly losing efficiency. They also usually contain lead, a toxin.

Still, Yao said, the materials hold great promise for the solar industry, even if they are unlikely to replace silicon entirely. Instead, he said, they could be used in conjunction with silicon, boosting efficiency to 30 percent or so.


How To Replace Air Conditionning And Save Electricity Bill

A team of researchers from Institut Teknologi Maju (ITMA), Universiti Putra Malaysia (UPM) has succeeded in inventing a new system, known as Nanotechnology for Encapsulation of Phase Change Material (NPCM) that can bring down room temperature in buildings, thus minimising the use of air-conditioning or heating systems, and saving electricity bill.

skyscraper in the desertHead of research team, Prof. Dr. Mohd Zobir Hussein said the encapsulation technology could change material at nano-sized regime which is good for use as thermal energy storage media. “This NPCM method is the first of its kind in Malaysia that can absorb, store and release thermal heat when the surrounding temperature where the material is located is above or below melting temperature. These properties allow the phase change material to store the thermal energy when it melts and releases the energy when it solidifies,” he said.

If it is used as passive or active building component, it can help in controlling the internal building temperature fluctuations which will result in thermal-comfort buildings. This will reduce dependency of building occupants to air conditioning or heating systems and electricity consumption, indirectly reducing carbon dioxide emissionNPCM can be incorporated into cement or paint as active insulation materials and apply to the ceilings or walls of the buildings,” told Dr. Mohd Zobir Hussein  at a Press Conference during 2016 ITMA Innovation Day. He also said if it is incorporated into building components, it will not give any adverse effect to the structure integrity of the buildings.


How To Save The Bees

It’s a global phenomenon that worries beekeepers and environmentalistshoney bee colonies dying at an alarming rate. Here in Poland, bee population has halved in the past 15 years. A disease called nosemosis is one cause.


Nosemosis is a very serious disease which shortens the bees’ lifespan. Infected worker bees live for a very short time in the summer, about 8 to 12 days, while they normally live 36 days. So the productivity of the whole bee family decreases and bees also have problems with passing the winter“, says Aneta Ptaszinska from the Maria-Curie Sklodowska University in Lublin (UMCS – Poland).

Nosema disease, or nosemosis is a honey bee gut disease caused by microscopic fungi that spread through food or water. When consumed it attacks the insects’ intestines, causing them to constantly search for food and eventually die in the process. Some studies blame pesticides for having a negative influence on the bees’ immune system, which then cannot fight off the fungi. But Ptaszynska says a new drug developed by her team strengthens the immune system to help beat the disease.

On one hand they decrease the level of Nosemosis, we can clearly observe a decrease in the number of spores in the intestines of bees given the extracts. On the other hand, they increase the level of enzymes responsible for the immunological reaction of the insects, enzymes which recognize pathogens, foreign bodies. We assume that in this way the extracts help the bees overcome this disease“, comments Dr. Ptaszinska.  She adds that the floral extract is safe for human consumption, and is effective in more than 90 percent of cases. Bees are vital for the world’s food supply, pollinating the vegetables and fruits we eat and those eaten by the animals we then consume. The drug is undergoing patenting procedures, and the team hopes that it creates enough buzz to find the right partners for production and distribution soon.


How To Turn CO2 Into Rock

An international team of scientists have found a potentially viable way to remove anthropogenic (caused or influenced by humans) carbon dioxide emissions from the atmosphereturn it into rock.

The study, published today in Science, has shown for the first time that the greenhouse gas carbon dioxide (CO2) can be permanently and rapidly locked away from the atmosphere, by injecting it into volcanic bedrock. The CO2 reacts with the surrounding rock, forming environmentally benign minerals.


Measures to tackle the problem of increasing greenhouse gas emissions and resultant climate change are numerous. One approach is Carbon Capture and Storage (CCS), where CO2 is physically removed from the atmosphere and trapped underground. Geoengineers have long explored the possibility of sealing CO2 gas in voids underground, such as in abandoned oil and gas reservoirs, but these are susceptible to leakage. So attention has now turned to the mineralisation of carbon to permanently dispose of CO2.

Until now it was thought that this process would take several hundreds to thousands of years and is therefore not a practical option. But the current study – led by Columbia University, University of Iceland, University of Toulouse and Reykjavik Energy – has demonstrated that it can take as little as two years.

Lead author Dr Juerg Matter, Associate Professor in Geoengineering at the University of Southampton, says: “Our results show that between 95 and 98 per cent of the injected CO2 was mineralised over the period of less than two years, which is amazingly fast.”

Carbonate minerals do not leak out of the ground, thus our newly developed method results in permanent and environmentally friendly storage of CO2 emissions,” adds Dr Matter, who is also a member of the University’s Southampton Marine and Maritime Institute and Adjunct Senior Scientist at Lamont-Doherty Earth Observatory Columbia University. “On the other hand, basalt is one of the most common rock type on Earth, potentially providing one of the largest CO2 storage capacity.

Storing CO2 as carbonate minerals significantly enhances storage security which should improve public acceptance of Carbon Capture and Storage as a climate change mitigation technology,” says Dr Matter. “The overall scale of our study was relatively small. So, the obvious next step for CarbFix is to upscale CO2 storage in basalt. This is currently happening at Reykjavik Energy’s Hellisheidi geothermal power plant, where up to 5,000 tonnes of CO2 per year are captured and stored in a basaltic reservoir.”


3D Nano-structured Porous Electrodes Boost Batteries

Battery-life is increasingly the sticking point of technological progress.The latest electric vehicles can practically drive themselve, but only for so long. Outback energy woes look like they could be solved by solar and home energy storage, if the available batteries can be improved. And what about the Pokemon GO players, cutting hunting trips short due to the battery-sapping requirements of the app?

The solution could come from Sunshine Coast nanotechnology company Nano Nouvelle, which is developing a three-dimensional, nano-structured, porous electrode that it says will help overcome the limitations of today’s batteries.The company announced today that its ‘Nanodenanomaterials were being tested and trialled by two unnamed US specialist battery manufacturers.


CEO Stephanie Moroz said she hoped the profile of the trials would lead to wider adoption.“As Tesla proved with its Roadster EV sportscar, this sort of low-volume, high-margin starting point can provide a high visibility platform to demonstrate the benefits of innovative technology, which can accelerate its adoption by mass market manufacturers.”

Nano Nouvelle’s core technology, the Nanode uses tin as the electrode material, which has a much higher energy density than the current graphite technology. However, until now tin’s commercial use had been limited due to its tendency to swell during charging and subsequently lose energy.

This issue is overcome by the Nanode’s structure, made up of thin films of active material spread over a 3D and porous network of fibres, rather than stacked on a flat copper foil.

This enables the electrode structure to deal with the volume expansion of the tin while retaining dimensional stability at the electrode level. The result is batteries that can store the same amount of energy in a smaller volume, compared to commercial lithium ion batteries.

Moroz said she believed the nanotechnology could be easily incorporated into the existing battery manufacturing process. Moroz said she believed the nanotechnology could be easily incorporated into the existing battery manufacturing process.

We’re looking to make it plug and play for battery manufacturers,” she said.


Nanotechnologies Crush the Road Construction Costs

The solution for affordable road infrastructure development could lie in the use of nanotechnology, according to a paper presented at the 35th annual Southern African Transport Conference in Pretoria. The cost of upgrading, maintaining and rehabilitating road infrastructure with limited funds makes it impossible for sub-Saharan Africa to become competitive in the world market, according to Professor Gerrit Jordaan of the University of Pretoria, a speaker at the conference. The affordability of road infrastructure depends on the materials used, the environment in which the road will be built and the traffic that will be using the road, explained Professor James Maina of the department of civil engineering at the University of Pretoria. Hauling materials to a construction site contributes hugely to costs, which planners try to minimise by getting materials closer to the site. But if there aren’t good quality materials near the site, another option is to modify poor quality materials for construction purposes. This is where nanotechnology comes in.


Nanomaterial is really small; five nanometers are equivalent to 0.05mm,” explained Maina. The materials bind with the poor quality material which needs to be modified, and can then change the behaviour of the material.

For example, if the material is clay soil, it has a high affinity to water so when it absorbs water it expands, and when it dries out it contracts. Nanotechnology can make the soil water repellent. “Essentially, nanotechnology changes the properties to work for the construction process,” he said.

These nanotechnology-based products have been used successfully in many parts of the world, including India, the USA and in the West African region.
“We need to have roads to enable mass movement of people and goods,” said Maina. Well-maintained road infrastructure ensures optimal speed of movement, opening up economic opportunities for people. Moving goods safely is also important as damaged goods translate into economic cost, he explained. “For a country to be competitive globally, we need to reduce costs as much as possible. We need well maintained and well planned road infrastructure,” comments Maina.


Solar Cells: How To Boost Perovkite Efficiency Up To 31%

Scientists from the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) have discovered a possible secret to dramatically boosting the efficiency of perovskite solar cells hidden in the nanoscale peaks and valleys of the crystalline material.

Solar cells made from compounds that have the crystal structure of the mineral perovskite have captured scientists’ imaginations. They’re inexpensive and easy to fabricate, like organic solar cells. Even more intriguing, the efficiency at which perovskite solar cells convert photons to electricity has increased more rapidly than any other material to date, starting at three percent in 2009—when researchers first began exploring the material’s photovoltaic capabilities—to 22 percent today. This is in the ballpark of the efficiency of silicon solar cells.

Now, as reported online July 4 in the journal Nature Energy, a team of scientists from the Molecular Foundry and the Joint Center for Artificial Photosynthesis, both at Berkeley Lab, found a surprising characteristic of a perovskite solar cell that could be exploited for even higher efficiencies, possibly up to 31 percent.

Using photoconductive atomic force microscopy, the scientists mapped two properties on the active layer of the solar cell that relate to its photovoltaic efficiency. The maps revealed a bumpy surface composed of grains about 200 nanometers in length, and each grain has multi-angled facets like the faces of a gemstone. Unexpectedly, the scientists discovered a huge difference in energy conversion efficiency between facets on individual grains. They found poorly performing facets adjacent to highly efficient facets, with some facets approaching the material’s theoretical energy conversion limit of 31 percent. The scientists say these top-performing facets could hold the secret to highly efficient solar cells, although more research is needed.

perovskite solar panel

“If the material can be synthesized so that only very efficient facets develop, then we could see a big jump in the efficiency of perovskite solar cells, possibly approaching 31 percent,” says Sibel Leblebici, a postdoctoral researcher at the Molecular Foundry.

Leblebici works in the lab of Alexander Weber-Bargioni, who is a corresponding author of the paper that describes this research. Ian Sharp, also a corresponding author, is a Berkeley Lab scientist at the Joint Center for Artificial Photosynthesis. Other Berkeley Lab scientists who contributed include Linn Leppert, Francesca Toma, and Jeff Neaton, the director of the Molecular Foundry.


Nanotechnology Boosts Oil Recovery

As oil producers struggle to adapt to , getting as much oil as possible out of every well has become even more important, despite concerns from nearby residents that some chemicals used to boost production may pollute underground water resources.

Researchers from the University of Houston have reported the discovery of a nanotechnology-based solution that could address both issues – achieving 15 percent tertiary oil recovery at low cost, without the large volume of chemicals used in most commercial fluids. The solution – graphene-based Janus amphiphilic nanosheets – is effective at a concentration of just 0.01 percent, meeting or exceeding the performance of both conventional and other nanotechnology-based fluids, said Zhifeng Ren, MD Anderson Chair professor of physics. Janus nanoparticles have at least two physical properties, allowing different chemical reactions on the same particle.

The low concentration and the high efficiency in boosting tertiary oil recovery make the nanofluid both more environmentally friendly and less expensive than options now on the market, said Ren, who also is a principal investigator at the Texas Center for Superconductivity at UH. He is lead author on a paper describing the work, published June 27 in the Proceedings of the National Academy of Sciences.

oil well

Our results provide a novel nanofluid flooding method for tertiary oil recovery that is comparable to the sophisticated chemical methods,” they wrote. “We anticipate that this work will bring simple nanofluid flooding at low concentration to the stage of oilfield practice, which could result in oil being recovered in a more environmentally friendly and cost-effective manner.

The U.S. Department of Energy estimates as much as 75 percent of recoverable reserves may be left after producers capture hydrocarbons that naturally rise to the surface or are pumped out mechanically, followed by a secondary recovery process using water or gas injection.

Traditional “tertiaryrecovery involves injecting a chemical mix into the well and can recover between 10 percent and 20 percent, according to the authors. But the large volume of chemicals used in tertiary oil recovery has raised concerns about potential environmental damage.

Obviously simple nanofluid flooding (containing only nanoparticles) at low concentration (0.01 wt% or less) shows the greatest potential from the environmental and economic perspective,” the researchers wrote.

Previously developed simple nanofluids recover less than 5 percent of the oil when used at a 0.01 percent concentration, they reported. That forces oil producers to choose between a higher nanoparticle concentration – adding to the cost – or mixing with polymers or surfactants. In contrast, they describe recovering 15.2 percent of the oil using their new and simple nanofluid at that concentration – comparable to chemical methods and about three times more efficient than other nanofluids.


Hydrogen Fuel Stations

A Stanford University research lab has developed new technologies to tackle two of the world’s biggest energy challenges – clean fuel for transportation and grid-scale energy storageHydrogen fuel has long been touted as a clean alternative to gasoline. Automakers began offering hydrogen-powered cars to American consumers last year, but only a handful have sold, mainly because hydrogen refueling stations are few and far between.

silicone nanoconesStanford engineers created arrays of silicon nanocones to trap sunlight and improve the performance of solar cells made of bismuth vanadate

Millions of cars could be powered by clean hydrogen fuel if it were cheap and widely available,” said Yi Cui, associate professor of materials science and engineering at Stanford.

Unlike gasoline-powered vehicles, which emit carbon dioxide, hydrogen cars themselves are emissions free. Making hydrogen fuel, however, is not emission free: Today, making most hydrogen fuel involves natural gas in a process that releases carbon dioxide into the atmosphere.

To address the problem, Cui and his colleagues have focused on photovoltaic water splitting. This emerging technology consists of a solar-powered electrode immersed in water. When sunlight hits the electrode, it generates an electric current that splits the water into its constituent parts, hydrogen and oxygen. Finding an affordable way to produce clean hydrogen from water has been a challenge. Conventional solar electrodes made of silicon quickly corrode when exposed to oxygen, a key byproduct of water splitting. Several research teams have reduced corrosion by coating the silicon with iridium and other precious metals.
The researchers described their findings in two studies published this month in the journals Science Advances and Nature Communications. 

Writing in the June 17 edition of Sciences Advances, Cui and his colleagues presented a new approach using bismuth vanadate, an inexpensive compound that absorbs sunlight and generates modest amounts of electricity.

Bismuth vanadate has been widely regarded as a promising material for photoelectrochemical water splitting, in part because of its low cost and high stability against corrosion,” said Cui, who is also an associate professor of photon science at SLAC National Accelerator Laboratory. “However, the performance of this material remains well below its theoretical solar-to-hydrogen conversion efficiency.”

Bismuth vanadate absorbs light but is a poor conductor of electricity. To carry a current, a solar cell made of bismuth vanadate must be sliced very thin, 200 nanometers or less, making it virtually transparent. As a result, visible light that could be used to generate electricity simply passes through the cell.

To capture sunlight before it escapes, Cui’s team turned to nanotechnology. The researchers created microscopic arrays containing thousands of silicon nanocones, each about 600 nanometers tall.

Nanocone structures have shown a promising light-trapping capability over a broad range of wavelengths,” Cui explained. “Each cone is optimally shaped to capture sunlight that would otherwise pass through the thin solar cell.”

In the experiment, Cui and his colleagues deposited the nanocone arrays on a thin film of bismuth vanadate. Both layers were then placed on a solar cell made of perovskite, another promising photovoltaic material.

When submerged, the three-layer tandem device immediately began splitting water at a solar-to-hydrogen conversion efficiency of 6.2 percent, already matching the theoretical maximum rate for a bismuth vanadate cell.


Algae To Power Jets

Aviation giant Airbus hope algae could one day help power jets – and help airlines cut their C02 emissions. They’re working with the Munich Technical University (Germany) to cultivate the photosynthetic organisms in this lab. Algae here is cultivated in water with a salt content of 6-9 percent. A combination of light and carbon dioxide does the rest.


Primarily you need obviously algae cells that are able to generate fats and oils. In combination with CO2 and light these algae cells propagate and form algae biomass and under certain cultivation conditions, for example the lack of nitrogen in the cultivation media, these algae cells accumulate fats and oils in their cell mass and this can reach up to 50 to 70 percent of the total cell weight. That is quite a lot and once you formed that fat and oil you can actually extract it from the cell and convert it over a chemical process“, says  Thomas Brueck, Professor at Munich Technical University (TUM). In these open tanks algae grows 12 times faster than plants cultivated on soil, producing an oil yield 30 times that of rapeseed.

Algae fuel today is still in the state of research so today, we could probably not offer it at costs which are realistic to run an airline. But we are sure that over time, we will make it possible to offer kerosine made of algae for a competitive price“, comments Gregor von Kursell, Airbus Group Spokesman. The company says the project remains in its infancy. Researchers believe biofuel from algaculture could provide up to 5 percent of jetfuel needs by around 2050.


Nanotechnologies Boost Electric Car Batteries

On a drizzly, gray morning in April, Yi Cui weaves his scarlet red Tesla in and out of Silicon Valley traffic. Cui, a materials scientist at Stanford University here, is headed to visit Amprius, a battery company he founded 6 years ago. It’s no coincidence that he is driving a battery-powered car, and that he has leased rather than bought it. In a few years, he says, he plans to upgrade to a new model, with a crucial improvement: “Hopefully our batteries will be in it.” Cui and Amprius are trying to take lithium–ion batteries—today’s best commercial technology—to the next level. They have plenty of company. Massive corporations such as Panasonic, Samsung, LG Chem, Apple, and Tesla are vying to make batteries smaller, lighter, and more powerful. But among these power players, Cui remains a pioneering force.
Unlike others who focus on tweaking the chemical composition of a battery’s electrodes or its charge-conducting electrolyte, Cui is marrying battery chemistry with nanotechnology. He is building intricately structured battery electrodes that can soak up and release charge-carrying ions in greater quantities, and faster, than standard electrodes can, without producing troublesome side reactions.

Tesla Model 3

“He’s taking the innovation of nanotechnology and using it to control chemistry,” says Wei Luo, a materials scientist and battery expert at the University of Maryland, College Park.
In a series of lab demonstrations, Cui has shown how his architectural approach to electrodes can domesticate a host of battery chemistries that have long tantalized researchers but remained problematic. Among them: lithium-ion batteries with electrodes of silicon instead of the standard graphite, batteries with an electrode made of bare lithium metal, and batteries relying on lithium-sulfur chemistry, which are potentially more powerful than any lithium-ion battery. The nanoscale architectures he is exploring include silicon nanowires that expand and contract as they absorb and shed lithium ions, and tiny egglike structures with carbon shells protecting lithium-rich silicon yolks.