More Durable Fuel Cells For Hydrogen Electric Car

Take a ride on the University of Delaware’s (UDFuel Cell bus, and you see that fuel cells can power vehicles in an eco-friendly way. In just the last two years, Toyota, BMW and Honda have released vehicles that run on fuel cells, and carmakers such as GM, BMW and VW are working on prototypes.  If their power sources lasted longer and cost less, fuel cell vehicles could go mainstream faster. Now, a team of engineers at UD has developed a technology that could make fuel cells cheaper and more durable.

Hydrogen-powered fuel cells are a green alternative to internal combustion engines because they produce power through electrochemical reactions, leaving no pollution behind. Materials called catalysts spur these electrochemical reactions. Platinum is the most common catalyst in the type of fuel cells used in vehicles. However, platinum is expensive — as anyone who’s shopped for jewelry knows. The metal costs around $30,000 per kilogram. Instead, the UD team made a catalyst of tungsten carbide, which goes for around $150 per kilogram. They produced tungsten carbide nanoparticles in a novel way, much smaller and more scalable than previous methods.

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

The researchers made tungsten carbide nanoparticles using a series of steps including hydrothermal treatment, separation, reduction, carburization and more. The results are described in a paper published in Nature Communications.


Clean Renewable Source Of Hydrogen Fuel For Electric Car

Rice University scientists have created an efficient, simple-to-manufacture oxygen-evolution catalyst that pairs well with semiconductors for solar water splitting, the conversion of solar energy to chemical energy in the form of hydrogen and oxygen.

anode RiceA photo shows an array of titanium dioxide nanorods with an even coating of an iron, manganese and phosphorus catalyst. The combination developed by scientists at Rice University and the University of Houston is a highly efficient photoanode for artificial photosynthesis. Click on the image for a larger version

The lab of Kenton Whitmire, a Rice professor of chemistry, teamed up with researchers at the University of Houston and discovered that growing a layer of an active catalyst directly on the surface of a light-absorbing nanorod array produced an artificial photosynthesis material that could split water at the full theoretical potential of the light-absorbing semiconductor with sunlight. An oxygen-evolution  catalyst splits water into hydrogen and oxygen. Finding a clean renewable source of hydrogen fuel is the focus of extensive research, but the technology has not yet been commercialized.

The Rice team came up with a way to combine three of the most abundant metalsiron, manganese and phosphorus — into a precursor that can be deposited directly onto any substrate without damaging it. To demonstrate the material, the lab placed the precursor into its custom chemical vapor deposition (CVD) furnace and used it to coat an array of light-absorbing, semiconducting titanium dioxide nanorods. The combined material, called a photoanode, showed excellent stability while reaching a current density of 10 milliamps per square centimeter, the researchers reported.

The results appear in two new studies. The first, on the creation of the films, appears in Chemistry: A European Journal. The second, which details the creation of photoanodes, appears in ACS Nano.


Hydrogen Electric Car: New Storage System

Lawrence Livermore scientists have collaborated with an interdisciplinary team of researchers, including colleagues from Sandia National Laboratories, to develop an efficient hydrogen storage system that could be a boon for hydrogen-powered vehicles.

hydrogen lithiumHydrogenation forms a mixture of lithium amide and hydride (light blue) as an outer shell around a lithium nitride particle (dark blue) nanoconfined in carbon

Hydrogen is an excellent energy carrier, but the development of lightweight solid-state materials for compact, low-pressure storage is a huge challenge. Complex metal hydrides are a promising class of hydrogen storage materials, but their viability is usually limited by slow hydrogen uptake and release. Nanoconfinementinfiltrating the metal hydride within a matrix of another material such as carbon — can, in certain instances, help make this process faster by shortening diffusion pathways for hydrogen or by changing the thermodynamic stability of the material.

However, the Livermore-Sandia team, in conjunction with collaborators from Mahidol University in Thailand and the National Institute of Standards and Technology, showed that nanoconfinement can have another, potentially more important consequence. They found that the presence of internal “nano-interfaces” within nanoconfined hydrides can alter which phases appear when the material is cycled.

The key is to get rid of the undesirable intermediate phases, which slow down the material’s performance as they are formed or consumed. If you can do that, then the storage capacity kinetics dramatically improve and the thermodynamic requirements to achieve full recharge become far more reasonable,” said Brandon Wood, an LLNL materials scientist and lead author of the paper. “In this material, the nano-interfaces do just that, as long as the nanoconfined particles are small enough. It’s really a new paradigm for hydrogen storage, since it means that the reactions can be changed by engineering internal microstructures.”

The research is reported  in the journal Advanced Materials Interfaces


The Rise Of The Hydrogen Electric Car

Right now, if you want an alternative-fuel vehicle, you have to pick from offerings that either require gasoline or an electrical outlet. The gas-electric hybrid and the battery-powered car — your Toyota Priuses, Chevy Volts, and Teslas — are staples in this space. There are drawbacks for drivers of both types. You still have to buy gas for your hybrid and you have to plug in your Tesla — sometimes under less than favorable conditions — lest you be stranded someplace far away from a suitable plug. Beyond that, automakers have been out to find the next viable energy source. Plug-in vehicles are more or less proven to be the answer, but Toyota and a handful of other carmakers are investigating hydrogen.


That’s where the Toyota Mirai comes in. The Mirai‘s interior center stack has all the technology you would expect from a car that retails for $57,500, including navigation, Bluetooth, and USB connectivity. It’s all accessible by touch screens and robust digital displays.
A fill-up on hydrogen costs just about as much as regular gasoline in San Francisco. The Mirai gets an estimated 67 MPGe (67 Miles per gallon gasoline equivalent = 28,5 kilometers per liter)), according to Toyota.
It’s an ambitious project for Toyota because the fueling infrastructure for this car is minimal. There are only 33 public hydrogen-filling stations in the US, according to the US Department of Energy. Twenty-six of those stations are in California, and there’s one each in Connecticut, Massachusetts, and South Carolina.

If you include public and private hydrogen stations, then the total climbs to 58 — nationwide. Compare that to the more than 15,100 public electric-charging stations and the 168,000 retail gas stations in the US, and you can see the obvious drawback of hydrogen-powered cars. Despite this, the Mirai is an interesting project, and you must keep in mind that Japan at the Government level seems to bet on a massively hydrogen powered economy in the near future (fuel, heating, replacement of nuclear energy, trains, electric vehicles, etc…).


How To Store Hydrogen Fuel In Electric Cars

Layers of graphene separated by nanotube pillars of boron nitride may be a suitable material to store hydrogen fuel in cars, according to Rice University scientists. The Department of Energy has set benchmarks for storage materials that would make hydrogen a practical fuel for light-duty vehicles. The Rice lab of materials scientist Rouzbeh Shahsavari determined in a new computational study that pillared boron nitride and graphene could be a candidate.

hydrogenSimulations by Rice scientists show that pillared graphene boron nitride may be a suitable storage medium for hydrogen-powered vehicles. Above, the pink (boron) and blue (nitrogen) pillars serve as spacers for carbon graphene sheets (grey). The researchers showed the material worked best when doped with oxygen atoms (red), which enhanced its ability to adsorb and desorb hydrogen (white).


Just as pillars in a building make space between floors for people, pillars in boron nitride graphene make space for hydrogen atoms. The challenge is to make them enter and stay in sufficient numbers and exit upon demand.Shahsavari’s lab had already determined through computer models how tough and resilient pillared graphene structures would be, and later worked boron nitride nanotubes into the mix to model a unique three-dimensional architecture. (Samples of boron nitride nanotubes seamlessly bonded to graphene have been made.)

In their latest molecular dynamics simulations, the researchers found that either pillared graphene or pillared boron nitride graphene would offer abundant surface area (about 2,547 square meters per gram) with good recyclable properties under ambient conditions. Their models showed adding oxygen or lithium to the materials would make them even better at binding hydrogen. They focused the simulations on four variants: pillared structures of boron nitride or pillared boron nitride graphene doped with either oxygen or lithium. At room temperature and in ambient pressure, oxygen-doped boron nitride graphene proved the best, holding 11.6 percent of its weight in hydrogen (its gravimetric capacity) and about 60 grams per liter (its volumetric capacity); it easily beat competing technologies like porous boron nitride, metal oxide frameworks and carbon nanotubes.

The study by Shahsavari and Farzaneh Shayeganfar appears in the American Chemical Society journal Langmuir.


Electric Car: Nanofiber Electrodes Boost Fuel Cells By 30 Percent

At the same time Honda and Toyota are introducing fuel cell cars to the U.S. market, a team of researchers from Vanderbilt University, Nissan North America and Georgia Institute of Technology have teamed up to create a new technology designed to give fuel cells more oomph. The project is part of a $13 million Department of Energy program to advance fuel cell performance and durability and hydrogen storage technologies announced last month.

hydrogen fuel cells

Fuel cells were invented back in 1839 but their first real world application wasn’t until the 1960’s when NASA used them to power the Apollo spacecraft. Fuel cells need fuel and air to run, like a gasoline engine, but they produce electricity, like a battery. In hydrogen/air fuel cells, hydrogen flows into one side of the device. Air is pumped into the other side. At the anode, the hydrogen is oxidized into protons. The protons flow to the cathode where the air is channeled, reducing the oxygen to form water. Special catalysts in the anode and cathode allow these reactions to occur spontaneously, producing electricity in the process. Fuel cells convert fuel to electricity with efficiencies ranging from 40 percent to 60 percent. They have no moving parts so they are very quiet. With the only waste product being water, they are environmentally friendly.The $2.5 million collaboration is based on a new nanofiber mat technology developed by Peter Pintauro, Professor of Chemical Engineering at Vanderbilt, that replaces the conventional electrodes used in fuel cells. The nanofiber electrodes boost the power output of fuel cells by 30 percent while being less expensive and more durable than conventional catalyst layers. The technology has been patented by Vanderbilt and licensed to Merck KGaA in Germany, which is working with major auto manufacturers in applying it to the next generation of automotive fuel cells.

Conventional fuel cells use thin sheets of catalyst particles mixed with a polymer binder for the electrodes. The catalyst is typically platinum on carbon powder. The Vanderbilt approach replaces these solid sheets with mats made from a tangle of polymer fibers that are each a fraction of the thickness of a human hair made by a process called electrospinning. Particles of catalyst are bonded to the fibers. The very small diameter of the fibers means that there is a larger surface area of catalyst available for hydrogen and oxygen gas reactions during fuel cell operation. The pores between fibers in the mat electrode also facilitate the removal of the waste water. The unique fiber electrode structure results in higher fuel cell power, with less expensive platinum.

Hydrogen Electric Car Powered By Fuel Cells 4 Times More Efficient

Inspired by the humble cactus, a new type of membrane has the potential to significantly boost the performance of fuel cells and transform the electric vehicle industry. The membrane, developed by scientists from CSIRO (Australia) and Hanyang University in Korea, was described today in the journal Nature . The paper shows that in hot conditions the membrane, which features a water repellent skin, can improve the efficiency of fuel cells by a factor of four.

According to CSIRO researcher and co-author Dr Aaron Thornton, the skin works in a similar way to a cactus plant, which thrives by retaining water in harsh and arid environments.


Fuel cells, like the ones used in electric vehicles, generate energy by mixing together simple gases, like hydrogen and oxygen. However, in order to maintain performance, proton exchange membrane fuel cells – or PEMFCs – need to stay constantly hydrated,” Dr Thornton said.

At the moment this is achieved by placing the cells alongside a radiator, water reservoir and a humidifier. The downside is that when used in a vehicle, these occupy a large amount of space and consume significant power,” he added.

According to CSIRO researcher and co-author Dr Cara Doherty, the team’s new cactus-inspired solution offers an alternative. A cactus plant has tiny cracks, called stomatal pores, which open at night when it is cool and humid, and close during the day when the conditions are hot and arid. This helps it retain water,” Dr Doherty said. “This membrane works in a similar way. Water is generated by an electrochemical reaction, which is then regulated through nano-cracks within the skin. The cracks widen when exposed to humidifying conditions, and close up when it is drier. This means that fuel cells can remain hydrated without the need for bulky external humidifier equipment. We also found that the skin made the fuel cells up to four times as efficient in hot and dry conditions,” she added.

Professor Young Moo Lee from Hanyang University, who led the research, said that this could have major implications for many industries, including the development of electric vehicles.


Nanotechnology Improves Next Generation Of Batteries

In the global race to create more efficient and long-lasting batteries, some are betting on nanotechnology — the use of minuscule parts — as the most likely to yield a breakthrough. Improving batteries’ performance is key to the development and success of many much-hyped technologies, from solar and wind energy to electric cars. They need to hold more energy, last longer, be cheaper and safer. Research into how to achieve that has followed several avenues, from using different materials than the existing lithium-ion batteries to changing the internal structure of batteries using nanoparticles — parts so small they are invisible to the naked eye. Nanotechnology can increase the size and surface of batteries electrodes, the rods inside the batteries that absorb the energy. It does so by effectively making the electrodes sponge-like, so that they can absorb more energy during charging and ultimately increasing the energy storage capacity. Prague-based company HE3DA in Czech Republic has developed such a technology by using the nanotechnology to move from the current flat electrodes to make them three dimensional. With prototypes undergoing successful testing, it hopes to have the battery on the market at the end of this year.

Tesla Model 3

In the future, this will be the mainstream,” said Jan Prochazka, the president. He said it would be targeted at high-intensity industries like automobiles and the energy sector, rather than mobile phones, because that is where it can make the biggest difference through its use of his bigger electrodes.

In combination with an internal cooling system the batteries, which are being tested now, should be safe from overheating or exploding, a major concern with existing technologies. Researchers at the University of Michigan and MIT have likewise focused on nanotechnology to improve the existing lithium-ion technology. Others have sought to use different materials. One of the most promising is lithium oxygen, which theoretically could store five to 10 times the energy of a lithium ion battery, but there have been a number of technical problems that made it inefficient. Batteries based on sodium-ion, aluminium-air and aluminium-graphite are also being explored. There’s even research on a battery powered by urine.


Cost-effective Hydrogen Production From Water

Groundbreaking research at Griffith University (Australia) is leading the way in clean energy, with the use of carbon as a way to deliver energy using hydrogen. Professor Xiangdong Yao and his team from Griffith’s Queensland Micro- and Nanotechnology Centre have successfully managed to use the element to produce hydrogen from water as a replacement for the much more costly platinum.

Tucson fuel cellTucson fom Hyundai: A Hydrogen Fuel Cell Car

Hydrogen production through an electrochemical process is at the heart of key renewable energy technologies including water splitting and hydrogen fuel cells,” says Professor Yao. “Despite tremendous efforts, exploring cheap, efficient and durable electrocatalysts for hydrogen evolution still remains a great challenge. “Platinum is the most active and stable electrocatalyst for this purpose, however its low abundance and consequent high cost severely limits its large-scale commercial applications. “We have now developed this carbon-based catalyst, which only contains a very small amount of nickel and can completely replace the platinum for efficient and cost-effective hydrogen production from water.

In our research, we synthesize a nickel–carbon-based catalyst, from carbonization of metal-organic frameworks, to replace currently best-known platinum-based materials for electrocatalytic hydrogen evolution“, he adds. “This nickel-carbon-based catalyst can be activated to obtain isolated nickel atoms on the graphitic carbon support when applying electrochemical potential, exhibiting highly efficient hydrogen evolution performance and impressive durability.”

Proponents of a hydrogen economy advocate hydrogen as a potential fuel for motive power including cars and boats and on-board auxiliary power, stationary power generation (e.g., for the energy needs of buildings), and as an energy storage medium (e.g., for interconversion from excess electric power generated off-peak).


New Efficient Materials For Solar Fuel Cells

University of Texas at Arlington (UTA) chemists have developed new high-performing materials for cells that harness sunlight to split carbon dioxide and water into useable fuels like methanol and hydrogen gas. These “green fuels” can be used to power cars, home appliances or even to store energy in batteries.

solar fuel cells

Technologies that simultaneously permit us to remove greenhouse gases like carbon dioxide while harnessing and storing the energy of sunlight as fuel are at the forefront of current research,” said Krishnan Rajeshwar, UTA distinguished professor of chemistry and biochemistry and co-founder of the University’s Center of Renewable Energy, Science and Technology. “Our new material could improve the safety, efficiency and cost-effectiveness of solar fuel generation, which is not yet economically viable,” he added.

The new hybrid platform uses ultra-long carbon nanotube networks with a homogeneous coating of copper oxide nanocrystals. It demonstrates both the high electrical conductivity of carbon nanotubes and the photocathode qualities of copper oxide, efficiently converting light into the photocurrents needed for the photoelectrochemical reduction process. Morteza Khaledi, dean of the UTA College of Science, said Rajeshwar’s work is representative of the University’s commitment to addressing critical issues with global environmental impact under the Strategic Plan 2020.


Very Efficient Nanowires Store Solar Energy

California is committed to 33 percent energy from renewable resources by 2020. With that deadline fast approaching, researchers across the state are busy exploring options. Solar energy is attractive but for widespread adoption, it requires transformation into a storable form. This week in ACS Central Science, researchers report that nanowires made from multiple metal oxides could put solar ahead in this race. One way to harness solar power for broader use is through photoelectrochemical (PEC) water splitting that provides hydrogen for fuel cells. Many materials that can perform the reaction exist, but most of these candidates suffer from issues, ranging from efficiency to stability and cost. Peidong Yang from Berkeley University of California  and colleagues designed a system where nanowires from one of the most commonly used materials (TiO2) acts as a “host” for “guestnanoparticles from another oxide called BiVO4.


BiVO4 is a newly introduced material that is among the best ones for absorbing light and performing the water splitting reaction, but does not carry charge well while TiO2 is stable, cheap and an efficient charge carrier but does not absorb light well. Together with a unique studded nanowire architecture, the new system works better than either material alone. The authors state their approach can be used to improve the efficiencies of other photoconversion materials.


Solar Fuel Cell For Hydrogen Electric Car

Why not a solar cell that that produces fuel rather than electricity? Researchers at Eindhoven University of Technology (TU/e) (Netherlands) and FOM Foundation today present a very promising prototype of this in the journal Nature Communications. The material gallium phosphide enables their solar cell to produce the clean fuel hydrogen gas from liquid water. Processing the gallium phosphide in the form of very small nanowires is novel and helps to boost the yield by a factor of ten. And does so using ten thousand times less precious material.

hydrogen electric car
The electricity produced by a solar cell can be used to set off chemical reactions. If this generates a fuel, then one speaks of solar fuels – a hugely promising replacement for polluting fuels. One of the possibilities is to split liquid water using the electricity that is generated (electrolysis). Among oxygen, this produces hydrogen gas that can be used as a clean fuel in the chemical industry or combusted in fuel cells – in cars for example – to drive engines.

To connect an existing silicon solar cell to a battery that splits the water may well be an efficient solution now but it is a very expensive one. Many researchers are therefore targeting their search at a semiconductor material that is able to both convert sunlight into an electrical charge and split the water, all in one; a kind of ‘solar fuel cell’. Researchers at TU/e and FOM see their dream candidate in gallium phosphide (GaP), a compound of gallium and phosphide that also serves as the basis for specific colored leds.

has good electrical properties but the drawback that it cannot easily absorb light when it is a large flat surface as used in GaP solar cells. The researchers have overcome this problem by making a grid of very small GaP nanowires, measuring five hundred nanometers (a millionth of a millimeter) long and ninety nanometers thick. This immediately boosted the yield of hydrogen by a factor of ten to 2.9 percent. A record for GaP cells, even though this is still some way off the fifteen percent achieved by silicon cells coupled to a battery.

According to research leader and TU/e professor Erik Bakkers, it’s not simply about the yield – where there is still a lot of scope for improvement he points out: “For the nanowires we needed ten thousand less precious GaP material than in cells with a flat surface. That makes these kinds of cells potentially a great deal cheaper,” Bakkers says. “In addition, GaP is also able to extract oxygen from the water – so you then actually have a fuel cell in which you can temporarily store your solar energy. In short, for a solar fuels future we cannot ignore gallium phosphide any longer.”