What sends the environmental crowd into joy is that a hydrogen fuel cell’s emission is water vapor.  A fuel cell power plant only emitting water would be the nirvana of portable and mobile power.  There is a huge “but” in the way.

A tiny amount of water will kill the reaction that drives a hydrogen fuel cell.  Moving the water out is a difficult and as yet unresolved, engineering issue.  Until it’s mastered reliably and at low cost, hydrogen fuel cells will remain a dead end.  Even more concerning is fuel cells are actually stacked up cells to get to voltage, and just one cell in a water error kills the whole stack.  Two decades of worrying away at ideas has brought no solution that can be mass-produced.

Fuel Cell Cross Section Graphic. Click image for more info.

The water forms up in the fuel cell’s porous transport layer (PTL), which is not much thicker than a coffee filter. That’s where all the byproducts of the fuel cell’s power-generating reaction meet up with a catalyst and react to form the water vapor.

Allen, the John F. and Joan M. Calder Associate Professor in Mechanical Engineering at Michigan Tech points out it’s not easy to find out exactly what’s happening in the PTL. “Everything is compressed like crazy. You have to get the gases, hydrogen and air – to the catalyst, and you have to get the water away. Figuring out how to do this has largely been a matter of trial and error.”

Hope lies in the latest generation of hydrogen fuel-cell technologies that do an excellent job of managing water, but as new materials and designs enter the arena, the industry is again faced with a long, costly experimental process to determine the best configuration.

This is where Allen and his team with a new model come in.  “There’s a whole new class of catalysts coming out, and we want to make sure it doesn’t take another 20 years to optimize the materials set,” says Allen.

Optimizing those up-and-coming materials to get rid of water is especially difficult, because the movement of water in the PTL appears to be random. “But that’s what we’re trying to predict,” he says.

The Michigan Tech press release writer puts it this way: at high flow rates, water spreads out evenly. But when the flow rate is low, as it is in an operating fuel cell, it spreads out in irregular shapes like an amoeba, a process called “fingering.” Other factors come into play as well, including how saturated the PTL is.

Allen’s team incorporated those variables into a mathematical model with the aim of forecasting the movement of water. Then they tested it using four different types of PTL and found that they could predict how water would behave with a high degree of accuracy.

“We were really excited,” Allen says. “This is the first time anyone has validated a model in a real sample. We’re at the point where, by adjusting just one parameter, we are able to duplicate experimental results exactly.”

The team is taking the model further by incorporating temperature and evaporation into their model to make it an even better tool for fuel cell designers.

The publication of the findings took place back in December of 2011 with the press release just getting out last week.  The article, “Scaling Percolation in Thin Porous Layers,” published in the journal Physics of Fluids.

A polite reminder – hydrogen is a fuel not an energy source.  While one hopes the good professor and his team can drive to an economical and reliable fuel cell, the cost of the hydrogen is going to make or break the hydrogen economy.

So far the main sources of hydrogen are from natural gas with CO2 remaining, electrolysis of water which needs a electricity source that so far suggests 150% of the hydrogen energy store is needed to get to the 100% energy store in the hydrogen.

Plus hydrogen remains the devil to contain.  Hydrogen is the smallest atom and slips away almost at will.  No really convincing storage schemes seem practical yet.  And when it does escape, as it is highly reactive, the potential for accidents with serious personal injury and property damage is very high.

Still, Allen is leading to a good end.  Should the hydrogen formation and energy carrier of choice get sensible as suggested by using methanol or ammonia, then fuel cells could drive demand to mass production.

We wish Allen great success and hope the example he’s setting will transfer to the other side of the fuel cell where much safer, simpler and lower cost fuel stores such as methanol can become fuel cell fuels.  Then we should have some numbers on the cost to get hydrogen-energized work done.

The study published in the Journal of the American Chemical Society reports the key is adding gold to the catalyst formation process to yield a more uniform crystal structure and the new crystal removes carbon monoxide from the reaction.

That’s the news – getting the carbon monoxide away.  Platinum absorbs carbon monoxide in reactions involving fuel cells powered by organic materials like formic acid.  Palladium breaks down over time.  Both of these metals are very costly.

The Brown University created a triple-headed metallic nanoparticle that they say outperforms and outlasts all others at the anode end in formic-acid fuel-cell reactions. They report a 4-nanometer iron-platinum-gold nanoparticle (FePtAu), with a tetragonal crystal structure, generates higher current per unit of mass than any other nanoparticle catalyst tested.  Better yet, Brown’s triple metal nanoparticle performs nearly as well after 13 hours as it did at the start.

Gold Enhanced Fuel Cell Catalyst Crystal

That compares to another test built nanoparticle challenged under identical conditions that lost nearly 90% of its performance in just one-quarter of the time.

Shouheng Sun, chemistry professor at Brown and corresponding author on the paper said, “We’ve developed a formic acid fuel-cell catalyst that is the best to have been created and tested so far. It has good durability as well as good activity.”

The bit of gold starts the positive effect right at the beginning, when the crystals are built.  The gold acts as an atomic atom organizer of sorts, leading the iron and platinum atoms into neat, uniform layers within the nanoparticle.  Then the gold atoms then exit the interior and bind to the outer surface of the nanoparticle assembly.

Gold is effective at ordering the iron and platinum atoms because the gold atoms create extra space within the nanoparticle sphere at the outset. When the gold atoms diffuse from the space upon heating, they create more room for the iron and platinum atoms to assemble themselves. As a bonus the gold creates the crystallization chemists want in the nanoparticle assembly at a lower temperature.

Gold Enhanced Fuel Cell Catalyst Temperature Response. Image Credit: American Chemical Society.

In operation the gold also removes carbon monoxide (CO) from the reaction by catalyzing its oxidation. Otherwise the carbon monoxide, which binds well to iron and platinum atoms, would gum up the reaction. By essentially scrubbing it from the reaction, gold improves the performance of the combined iron-platinum catalyst.

The team decided to try gold after reading in the literature that gold nanoparticles were effective at oxidizing carbon monoxide – so effective, in fact, that gold nanoparticles had been incorporated into the helmets of Japanese firefighters. Indeed, the Brown team’s triple-headed metallic nanoparticles worked just as well at removing CO in the oxidation of formic acid, although it is unclear specifically why.

In the study paper the Brown team highlights the importance of creating an ordered crystal structure for the nanoparticle catalyst. The gold additive helps researchers get a crystal structure called a “face-centered-tetragonal,” a four-sided shape in which iron and platinum atoms essentially are forced to occupy specific positions in the structure, creating more order. By imposing atomic order, the iron and platinum layers bind more tightly in the structure, thus making the assembly more stable and durable, essential to better-performing and longer-lasting catalysts.

The Brown team’s tests are extraordinary.  The paper reports experiments showing the FePtAu catalyst reached 2809.9 mA/mg Pt (mass-activity, or current generated per milligram of platinum), “which is the highest among all NP (nanoparticle) catalysts ever reported.”. After 13 hours, the FePtAu nanoparticle has a mass activity of 2600mA/mg Pt, or 93% of its original performance value. The Brown team pointed out in comparison, the well-received platinum-bismuth nanoparticle has a mass activity of about 1720mA/mg Pt under identical experiments, and is four times less active when measured for durability.

The team also notes that other metals may be substituted for gold in the nanoparticle catalyst to improve the catalyst’s performance and durability.  The team says in the study “This communication presents a new structure-control strategy to tune and optimize nanoparticle catalysis for fuel oxidations.”

This work is a breakthrough concept in crystal catalyst design.  The ideas explored are going to have significant impact as the concept finds application across the catalyst field.  The matter of scale will come up, but right out of the gate the team is addressing life expectancy with great results.

Who’s on the team?  Inquiring headhunters will want to know.

Sen Zhang, a third-year graduate student in Sun’s lab, helped with the nanoparticle design and synthesis. Shaojun Guo, a postdoctoral fellow in Sun’s lab performed electrochemical oxidation experiments. Huiyuan Zhu, a second-year graduate student in Sun’s lab, synthesized the FePt nanoparticles and ran control experiments. The other contributing author is Dong Su from the Center for Functional Nanomaterials at Brookhaven National Laboratory, who analyzed the structure of the nanoparticle catalyst using the advanced electron microscopy facilities there.

Hold on – the funding was from ExxonMobil and the U.S. Department of Energy.

May the tech spread far and wide.  Congratulations!

Apple has gone so far as to file patent applications named “Fuel Cell System to Power a Portable Computing Device” and “Fuel Cell System Coupled to a Portable Computing Device” – ideas not to be taken lightly.

It not a great surprise to close Apple watchers, Apple has filed other patent applications for light weight hydrogen fuel cells. Those patents, which were brought to light this past October, described a building process where multiple fuel cells are connected by a power bus in a parallel pattern, and a voltage-multiplying circuit is added for additional voltage from the stack.

Apple hopes to utilize these lighter, more efficient fuel cells in its mobile products in an effort to promote renewable energy sources and offer devices with the ability to run for days or even weeks without refueling, according to the patent applications. The devices will also be lighter and less bulky due to the lack of traditional batteries.

The interesting thing and idea to watch is Apple wants to integrate fuel cells right into their electronics.  No fuel cartridge needed.  But Apple allows creating a hydrogen fuel cell system that is cost-effective is a challenge.

The puzzle remains how hydrogen gas storage costs are going to make fuel cells economically viable, hydrogen is very difficult to store.  The smallest atom making the smallest molecule in H2 form needs compressed or exotic materials to keep it in one place.

The more interesting fuel cells rely on low cost stores of hydrogen in methanol or ethanol, liquids that have very high hydrogen density and only need plastic tanks at atmospheric pressure.

Apple’s patent application isn’t clear on their choice of fuels, either hydrogen or a hydrocarbon.  Apple states that alternative fuel cells may correspond to solid oxide fuel cells, molten carbonate fuel cells, direct methanol fuel cells, alkaline fuel cells, and/or other types of fuel cells.

Another part of the appeal is regulating a fuel cell’s operating parameter by directly charging an external battery with the fuel cell allowing the control process to be highly reliable.

Direct Methanol Fuel Cell by NASA. Click image for the largest view.

Meanwhile the U.S. Department of Defense, with the world’s largest fuel bill and likely the largest buyer of batteries is hard at the Direct Methanol Fuel Cell.  The U.S. Army is especially interested in hydrogen based fuel cell technology, says Maj. Mark Owens, which drastically reduces the amount of batteries that soldiers carry on dismounted missions. Owens’ shop, the PM Soldier Warrior, studied one three-day mission with a company-sized element and found that the fuel cell reduced the amount of batteries they carried by 600 pounds.  The test was the 1st Battalion of the 1st Infantry Division deployed to Afghanistan in 2011 with their rucksacks full of experimental renewable energy equipment.

The fuels cells are powered by reformed methanol – meaning it’s slightly watered-down – and “get lighter as time goes on,” as the fuel is used Owens says, “and the case weighs almost nothing.” Still, the rucksack-packable fuel-cell generator weighs 36 lb., according to Army documents. “Obviously, we want to get the weight down as much as possible,” Owens says. Also under evaluation is a 4.6-lb. wearable fuel cell that generates 50 watts of continuous power for 10 hours.

The problem is the money – all the fuel cells from simple hydrogen to those reacting heavy petrochemicals like kerosene all rely in expensive and rare elements like platinum, palladium and even rhodium.  And they run hot, 100s of degrees centigrade.  While the Finns have come up with a much less costly way to use the metals platinum and palladium, the investment will still be very substantial and the growth of the industry will simply push the metal prices higher.

Still, there are glimmers of research looking for ways to build fuel cells without the precious metal component.  One small break, in an industry building and selling fuel cells in specialized uses with great regularity, offers hope that mass markets can be addressed.

Bloom Energy can build fuel cells reacting with natural gas, or methane fuel for sensible prices.  Bloom and many others can be expected to be looking for ways to downsize and use liquid fuels. There is intense interest and cash on the line for the market right now.

2012 might be the year a fuel cell comes out that runs under the temperature of boiling water, and runs on cheap, energy dense and abundant, natural gas, ethanol or methanol.

So far details are rare, but you can be sure there will news coming soon.

For a comparison, the common quote for the amount of iron mined in history is a cubic mile or 147,197,952,000 cubic feet.  Now platinum is more rare, the oft-heard quote is mining over history has turned out 25 cubic feet, a block 5 feet on each side, about 1/15 the amount of gold.  That’s a massive difference.

Curiously with the world economy slowed down the price of platinum is lower than gold, a situation that will not last when the economy does pick up either by demand or a drop in gold’s price from an increase in confidence.  The main industrial use is catalytic converters for automobiles – and increasing global automobile demand in emerging markets with an interest in pollution control will likely move prices higher.

Meanwhile palladium may become harder than platinum to acquire.  Russia produces 50% of palladium’s annual supply and Russia has been selling off strategic stockpiles.  In simple terms, the use of Russian palladium stockpiles for current use will turn up later as reductions of the amount available to the market.

Gold Platinum & Palladium Nuggets Shown Left to Right. Click image for the largest view.

For now these are “cheap” as platinum trades 31% below its February 2008 high of $2,273 and palladium is trading 38% below its all-time high of almost $1,100 in January 2001.  That brings us to:

An Aalto University in Finland research team has developed a new and significantly cheaper method of manufacturing fuel cells by preparing nanoparticle metal catalysts for fuel cells by using atomic layer deposition (ALD).  The ALD method requires 60% less of the noble metals than current methods.

Docent Tanja Kallio at Aalto said, “This is a significant discovery, because researchers have not been able to achieve savings of this magnitude before with materials that are commercially available.”

The most commonly used fuel cells cover the anode with expensive noble metal powder, which reacts well with the fuel.  The Aalto study’s ALD method can cover the anode much thinner and more evenly than current production methods, which lowers costs and increases quality.

Palladium Preparation for ALD. Image Credit: Adolfo Vera, Aalto University. Click image for the largest view.

The Finn’s idea is to develop better alcohol fuel cells using methanol or ethanol as their fuel. It’s easier to handle and store alcohols than trying to use hydrogen. In alcohol fuel cells, it is also possible to use palladium as a catalyst.

As we noted above, for now platinum is about twice as expensive as palladium.  This means that alcohol fuel cells using palladium would offer a more economical product to the market.

Fuel cells are very efficient and can create electricity that produces very little or even no pollution, making more energy and requiring less fuel than other devices of equal size. They are also quiet and require low maintenance, because there are no moving parts.

When catalyst breakthroughs come and production costs can be lowered, fuel cells are expected to power electric vehicles and replace batteries, along with other jobs. Despite their current high price, fuel cells have already been used for a long time to produce energy in isolated environments, such as spacecraft.

The Aalto team’s results, published in the Journal of Physical Chemistry C. are based on preliminary testing with fuel cell anodes using a palladium catalyst. The Aalto team believes commercial production could start in 5-10 years.

Now if someone would find a huge palladium and platinum supply this would go big.

A cathode made with the best electrocatalyst from the team’s work, tested in H2O2, has a power density of 0.75 W cm−2 at 0.6 V, a meaningful voltage for polymer-electrolyte-membrane fuel cells operation, comparable with that of a commercial Pt-based cathode tested under identical conditions.

The alloy is iron-acetate/phenanthroline/zeolitic-imidazolate framework built into an electrocatalyst.  The zeolitic-imidazolate-framework serves as a microporous host for phenanthroline and ferrous acetate to form a precursor that is subsequently heat-treated. The new catalyst shows increased volumetric activity and enhanced mass-transport properties.

Iron Based Catalyst SEM Images. Image Credit: INRS. Click image for the larget view.

INRS has been at this a while having pioneered the development of the first high-performance iron-based catalyst for fuel cells.  The scientist’s second advance of a new and improved iron-based catalyst is capable of generating even more electric power.  The goal is to match or better platinum in fuel cells for transportation applications. So far only platinum-based catalysts have been able to produce adequate performance.

The new research findings are from the team of Professor Jean-Pol Dodelet.  Whose press release narrative runs, “With these new and promising results, we bolster the prospect of iron-based catalysts replacing platinum ones in the electrochemical reduction of oxygen, one of two reactions needed to activate the electric power generator we call a fuel cell. Platinum is rare and very costly, whereas iron is the second most abundant metal on earth and is inexpensive.”

The good professors optimism shows with, “Thanks to this breakthrough we are nearing the day when we will be able to drive electric-electric hybrid vehicles — i.e. battery and fuel cell powered — , which can potentially free us from our current dependence on oil to power our cars.”

Keep in mind, as French speaking folks, these Canadians are an interesting mix of North American car culture and European social connections.  The motivation – and opportunity – to make a major and adoptable contribution with worldwide implications is possible.

Working at the Énergie Matériaux Télécommunications Research Centre in Varennes, Québec, these INRS scientists are now focusing on the improvement of the long-term stability (at least 5,000 hours) of these promising new catalysts. “The next step is the most important because it will automatically lead to a high value commercial product, not only for car manufacturers but also for all industrial sectors that use electric power generators or manufacture their components,” explained Mr. Dodelet.

It’s still a long way to go.  The press release, while in French and translates easily and clearly, no offering of the fuel used is made. One assumes that hydrogen gas would be the first candidate, but real sales volume is going to need methane, methanol, plus ethanol fuel use capability. Relying on hydrogen gas for fuel in the face of the economic scale for natural gas and the alcohols isn’t thinking through to the market economics.

But using iron to cover half the reaction in a fuel cell at essentially the same performance of platinum is a breakthrough. The explanation of the construction of the catalyst isn’t noting just how it’s formed until the end, which offers quite a bit of speculation.  Lab work is just like that – but commercialization has to have much more solid answers.

The INRS is a young university.  A major research hit that goes commercial and really makes a difference including big investments, lots of jobs and sales in the millions is just what the school needs.

Almost there – we hope.

A room temperature operation seizes attention; formic acid makes for a set of questions.

Dr. Andrzej Borodziński at the Institute of Physical Chemistry of the Polish Academy of Sciences in Warsaw (IPC PAS) notes some worthwhile points.  The biggest obstacle to marketing of hydrogen fuels is the storage of hydrogen.  The obstacle remains extremely technologically challenging and still is waiting for satisfactory solutions.  Methanol, an alternative to fuel cells powered by pure hydrogen is toxic and the methanol powered fuel cells produce low power and are operated at a relatively high and so potentially hazardous temperatures at or beyond 90º C.  Neither produces power in a consumer friendly small appliance package of great desirability.

As the technology sits today the best present fuel cells, powered by hydrogen, reach up to 60% in scaleable operation. For comparison, the efficiency of low-compression engines is as low as 20%.

Fuel cells theoretical efficiency of converting chemical energy into electric power can reach even one hundred percent.  There is hardly a consumer portable electronics user who isn’t irritated by problems with power supply. The batteries run out quickly and require continuous replacements or take a long time charging.

The IPC PAS has a developed new catalyst they believe will enable a widespread use of fuel cells. Room temperature operation is a very good start.  They’re suggesting the new fuel cell will be cheap, durable, lightweight and environmentally friendly powered by formic acid.

The IPC PAS group is claiming the efficiency and power of their fuel cells are clearly higher than those powered by methanol.  To make it work the group has developed an efficient and durable catalyst.

Dr. Borodziński says, “The catalyst developed by us has initially lower activity then the existing catalysts made of pure palladium. However the difference disappears after two hours of operation. And further on it only gets better. Our catalyst is stable in operation, whereas the activity of a pure palladium-based catalyst decreases over time.”  That’s really new – a catalyst that improves over time.

Here’s another important plus, the new catalyst preserves its properties while operated in formic acid of low purity. Such formic acid can be easily produced in large quantities, also from biomass, so the fuel for new fuel cells would be very cheap.

One is starting to think the Pols are on to something.

Formic acid produced from biomass would be a fully environment friendly fuel. The reactions involving formic acid in the fuel cell generate the products of water and carbon dioxide. The CO2 is considered a greenhouse gas, but the biomass is obtained from plants which use carbon dioxide for their growth. As a result, formic acid produced from biomass and consumed in fuel cells would not change the content of carbon dioxide in atmospheric air, it’s just another CO2 step in the carbon cycle.

The risk of natural environment contamination by formic acid is also low.  Formic acid occurs naturally in small quantities and is degraded in the environment without being damaging.  A spill of low purity isn’t going to be a huge disaster.  Well, it will be a smelly mess.

But the potential is considerable.  The formic acid fuel cells could find homes in portable electronic devices – mobile phones, laptops or GPS-based devices. They could also be installed as power supply sources in vehicles, from wheelchairs through electric bicycles up to yachts.   High efficiency and power at low operating temperatures offer a much stronger consumer incentive.

At the IPC PAS the research is being undertaken first on battery substitutes based on formic acid fuel cells. The researchers expect that a prototype of a commercial device should be ready within a couple of years.

Just what is that formic acid? Formic acid, aka methanoic acid, is the simplest carboxylic acid, a family of chemicals with a carbon component.  Formic acid is HCO2H, or two hydrogen atoms, with a CO2 segment.  Formic acid has been known for a long time, is colorless, gives off fumes of an unpleasant scent, and mixes well with water.  As it is not flammable when the concentration is below 85% its safety could be desirable.  It can be used as a kind of food additive as a preservative at very low concentration.

On the hand formic acid isn’t pleasant to be around and in high concentrations can damage the skin and eyes.  Animals, including people metabolize and eliminate formic acid easily, but an overdose of formic acid and the formaldehyde made as it metabolizes can damage optic nerves.

But highly concentrated formic acid just decomposes into CO2 and water.  The material is an irritant, corrosive, and could be ignited in pure enough form.  But on the whole, and the reality, the stuff being around all the time anyway, it’s a pretty kindly material which if used as a fuel would be quite a handy thing.  Just don’t spill it – but that applies to virtually everything in the fuels field.

Keep that research going – this idea, as unusual as it seems, has great potential.

This is very good news.  A much smaller methanol fuel cell is on the market in Japan, but the JPL fuel cell puts out a worthwhile 300 watts, or 2.5 amps at the customary U.S. 120 volts.  That’s enough to run a room’s lights, or a mid range PC, or a fairly good sized LCD TV.  Now we’re getting somewhere.

JPLs Direct Methanol Fuel Cell Prototype. Click image for the largest view.

The JPL’s novel fuel cell technology uses liquid methanol as a fuel to produce electrical energy, and does not require any fuel processing. The consumer value in methanol is it’s a simple liquid that doesn’t evaporate off quickly and can be safely handled much like gasoline, except that it’s much harder to ignite.  These points cut way down on the accessory kit to the fuel cell for fuel storage and handling.  Compared to the complexity of storing gaseous hydrogen, methanol is simple and very cheap.  Methanol use can be as simple as putting the nozzle in the tank.

Pure water and carbon dioxide are the only byproducts of the JPL fuel cell, and no pollutants are emitted. Direct Methanol Fuel Cells offer several advantages over other current fuel cell systems, especially with regard to simplicity of design and higher energy density.

Methanol is a very good store of hydrogen with four hydrogen atoms per carbon and oxygen atom in each molecule. It stores in common metal and plastic containers without pressure.  If not spilled and ignited, it’s quite safe with existing common sense.  It’s a fuel Joe and Jane everyone can cope with without a new learning curve.

JPL Power Technology Program Manager Rao Surampudi in explaining said that USC worked with JPL in the development and advancement of this technology for defense and commercial applications, “JPL invented the Direct Methanol Fuel Cell concept and also made significant contributions to all the facets of the technology. These contributions include: development of advanced catalyst materials, high-performance fuel cell membrane electrode assemblies, compact fuel cell stacks, and system designs.”

Over the years, those applications have expanded from the original defense applications to include such uses as battery chargers for consumer electronics, electric vehicles, stand-alone power systems, and uninterrupted/emergency power supplies.  From 1989 to 1998, the Defense Advanced Research Projects Agency (DARPA) funded JPL and USC to develop direct methanol fuel cells for future defense applications. Inventors on the JPL team include Surampudi, Sri. R. Narayanan, Harvey Frank, Thomas Valdez, Andrew Kindler, Eugene Vamos and Gerald Halpert. The USC inventor team includes G.K. Surya Prakash, Marshall Smart and Nobel Laureate George Olah.

Erik Brandon, current Electrochemical Technologies group supervisor at JPL said, “We are looking forward to working closely with the fuel cell industry to further develop this technology to meet future market needs.”

Gerald Halpert, former Electrochemical Technologies group supervisor at JPL believes, “This fuel cell may well become the power source of choice for energy-efficient, non-polluting military and consumer applications.”  Pure water and carbon dioxide are the only byproducts of a Direct Methanol Fuel Cell, and no pollutants are emitted.

The press release is not exactly packed with technical data – its rather absent, instead.  We’re looking for fuel efficiency, which one would expect to be high, but how high?

The photo about suggests the prototype fits within a briefcase to medium size luggage compartment, which is very good and the photo is of a prototype as well.

In any case, a deal for U.S technology is done at a wattage that is significant using a fuel that most folks could make at home like any moonshiner.  Methanol production isn’t quite the task the ethanol presents, nor so choosy about what raw bio materials can be used.

Uprating, downsizing and powering scooters or electric bicycles looks to be an imminent idea.  It’s a ways off to powering an automobile, but the attraction seems irresistible.  But the U.S. market seed has now been set.  When and where can I buy one?

Los Alamos researchers Gang Wu, Christina Johnston, and Piotr Zelenay, joined by researcher Karren More of the Oak Ridge National Laboratory, developing a polymer-electrolyte hydrogen fuel cell to convert hydrogen and oxygen into electricity, avoiding the use of expensive platinum. Environmentally friendly fuel cells might replace current power sources in everything from personal data devices to automobiles, if the hydrogen supply can be worked out at low cost.

The team of colleagues developed non-precious-metal catalysts for the part of the fuel cell that reacts with oxygen. The catalyst uses carbon, partially derived from polyaniline in a high-temperature process, and inexpensive iron and cobalt instead of platinum.  The result is high power output, good efficiency, and promising longevity. The researchers found that fuel cells containing the carbon-iron-cobalt polymer catalyst (CICP) synthesized by Wu not only generated electrical currents comparable to the output of precious-metal-catalyst fuel cells, but held up favorably when cycled on and off – a condition that can damage inferior catalysts relatively quickly.

PANI FeCo-C Catalyst. Click image for more info.

The new CICP catalyst fuel cells effectively completed the conversion of hydrogen and oxygen into water, rather than producing large amounts of undesirable hydrogen peroxide. Inefficient conversion of the fuel, which generates hydrogen peroxide, can reduce power output by up to 50 percent, and also has the potential to destroy the fuel cell’s membranes. The CICP catalysts synthesized at Los Alamos create extremely small amounts of hydrogen peroxide, even when compared with the state-of-the-art platinum-based oxygen-reduction catalysts.  From a users point of view this is quite good news because the removal of the hydrogen peroxide can be a hazardous nuisance.

Based on the performance results of the CICP catalyst the researcher team has filed a patent for it.

LANLs Wu front and Zelenay Inspect Data. Click image for the largest view.

Facing into the platinum cost problem is deal breaker for fuel cells.  Alternatives, especially ones that simplify operation is a great step forward.  Zelenay said, “The encouraging point is that we have found a catalyst with a good durability and life cycle relative to platinum-based catalysts. For all intents and purposes, this is a zero-cost catalyst in comparison to platinum, so it directly addresses one of the main barriers to hydrogen fuel cells.”

The next step in the team’s research will be to better understand the mechanism underlying the carbon-iron-cobalt catalyst. Micrographic images of portions of the catalyst by researcher Ms. More have provided some insight into how it functions, but further work must be done to confirm theories by the research team. Completing an understanding should lead to improvements in non-precious-metal catalysts, further increasing their efficiency and lifespan.

Zelenay could be effused a bit at the thought of zero-cost, but getting away from thousands or tens of thousands of dollars for the catalyst in fuel cells paints an opportunity that might look like zero in comparison if the CICP catalyst is made in mass volume.

If the team’s fuel cell life expectancy gets far into the tens of thousands of cycles and the cost is low enough the hydrogen fuel production and the storage issues will command much more serious attention with even more investment and innovation.  Hydrogen isn’t cheap and still is a devil to hang onto over time.

But a very low cost fuel cell changes the hydrogen economic picture completely.  And further work might turn up a very low cost fuel cell that can use methane or light alcohols.  It is good to see that the widely read journal Science published the paper. Market traction is something this team needs.  For those in the business a full read of the paper is worthwhile.

Pt-BMG Nanowires Array for Fuel Cells. Click image for the largest view. Image credit Golden Kumar and Miriam Schroers.

One reason (other than cost) fuel cells aren’t widely adopted is their lack of endurance.  The catalysts used in today’s state-of-the-art fuels cells break down over time, inhibiting the chemical reaction that converts fuel into electricity. Additionally, current technology relies on small particles coated with the catalyst; but the catalyst particles’ limited surface area means only a fraction of the catalyst is available at any given time.

Fuel cells have the promise to be a cleaner and far more efficient solution to the future’s energy production needs, with potential applications in everything from small electronics to over the road vehicles.  The potential could get to powering airplanes – the light weight potential and efficiency are very strong draws for research.

Yale engineers Jan Schroers and André Taylor have developed miniscule nanowires made of an innovative metal alloy known as a bulk metallic glass (BMG) that have high surface areas, thereby exposing more of the catalyst to the fuel. The catalyst in the nano wire support also maintains its activity longer than traditional fuel cell catalyst systems.

In comparison current fuel cell technology uses carbon black, an inexpensive and electrically conductive carbon material, as a support for platinum catalyst particles. The carbon transports electricity, while the platinum is the catalyst that drives the production of electricity. The more platinum particles the fuel is exposed to, the more electricity is produced. Here’s the problem – carbon black is porous, so the platinum that locates to the inner pores may not be exposed. Then add in that carbon black also tends to corrode over time.

Taylor points this out saying, “In order to produce more efficient fuel cells, you want to increase the active surface area of the catalyst, and you want your catalyst to last.”

Pt-BMG Nanowires for Fuel Cells Closeup. Click image for the largest view. Image credit Schroers and Taylor

The Yale team is using a compound of Pt_57.5Cu_14.7Ni_5.3P_22.5 for the bulk metallic glass (Pt-BMG) and usies a facile and scalable nanoimprinting approach to build the nanowires. That creates a dealloyed high surface area nanowire catalyst with high conductivity and activity for methanol and ethanol oxidation. That’s right – the common alcohols ethanol and methanol.At 13 nanometers in scale (about 1/10,000 the width of a human hair), the Schroers and Taylor Pt-BMG nanowires are about three times smaller than carbon black particles. The nanowires’ long, thin shape gives them much more active surface area per mass compared to carbon black. In addition, rather than sticking platinum particles onto a support material, the Yale team incorporated the platinum into the nanowire alloy itself, ensuring that it continues to react with the fuel over time.

After 1000 cycles, these nanowires are maintaining 96% of their performance, some 2.4 times as much as conventional platinum carbon (Pt/C) catalysts. These properties make the Pt-BMG catalyst an ideal candidate for widespread commercial use such as for energy conversion/storage and sensors.  Technically one question jumps out, just how recyclable is the nanowire catalyst?  The platinum is very expensive.  Endlessly recycling the whole of the active part of a fuel cell would have a huge impact on the ability to build market.

Schroers explains it’s the nanowires’ unique chemical composition that makes it possible to shape them into such small rods using a hot-press method.  Schroers has developed other BMG alloys that can also be blow molded into complicated shapes. The Pt-BMG nanowires also conduct electricity better than carbon black and carbon nanotubes, and are less expensive to process.  That suggests less electrical resistance heat buildup and lower manufacturing costs.

So far Taylor has tested the Pt-BMG catalyst system for alcohol-based fuel cells (including those that use ethanol and methanol as fuel sources), but the team says the system could be used in other types of fuel cells.

“This is the introduction of a new class of materials that can be used as electrocatalysts,” Taylor said. “It’s a real step toward making fuel cells commercially viable and, ultimately, supplementing or replacing batteries in electronic devices.”

The ACS Nano paper authors also include Marcelo Carmo, Ryan C. Sekol, Shiyan Ding and Golden Kumar (all of Yale University).

Last week saw another take on fuel cell development. One hopes these various teams are looking at each other’s papers and thinking about how to get the various very good ideas to work together.  Then maybe the fuel cell market can get somewhere more mass in scale and build up some industrial infrastructure.

Meanwhile more information would be useful.  Press releases and paper abstracts are fine, but if this is as good as its implied, costs and outputs need much more disclosure.

The addition of the extremely small nanocrystals to a solid electrolyte material is showing the potential to considerably raise the efficiency of solid electrolyte fuel cells.  The electrolyte is usually a liquid, but this has a number of drawbacks. The liquid has to be very well enclosed, for example, and it takes up a relatively large amount of space.

PhD student Lucas Haverkate said, “It would therefore be preferable to have an electrolyte made of solid matter. Unfortunately though, that has disadvantages as well. The conductivity in solid matter is not as good as it is in a liquid.”

This points up the researchers initial goal. The team at TU Delft was concentrating their efforts on improving electrolyte materials, the material between two electrodes used in a fuel cell or a battery. The better the characteristics of the electrolyte, the better, more compactly or more efficiently the fuel cell or battery works.

Haverkate continues, “In a solid matter you have a network of ions, in which virtually every position in the network is taken. This makes it difficult for the charged particles (protons) to move from one electrode to another. It’s a bit like a traffic jam on a motorway. What you need to do is to create free spaces in the network.”

Haverkate explains that one of the ways of achieving this, and therefore of increasing conductivity in solid electrolytes, is to add nanocrystals (of seven nanometres to around fifty nanometres), of titanium dioxide.” A characteristic of these TiO2 crystals is that they attract protons, and this creates more space in the network.” The nanocrystals are mixed in the electrolyte with a solid acid (CsHSO4). This latter material ‘delivers’ the protons to the crystals. “The addition of the crystals appears to cause an enormous leap in the conductive capacity, up to a factor of 100.”

That kind of conductivity improvement is going to have a worthwhile impact.  A reduction in the resistance is implied, thus one of the sources of heat should be reduced.

This is a remarkable achievement by the TU Delft team and has led to two publications in the scientific journal Advanced Functional Materials. Last December, Haverkate published an article on the theory behind the results. His fellow PhD student, Wing Kee Chan, is the main author of a second paper that’s appeared in the same publication this week. Chan focused on the experimental side of the research. “The nice thing about these two publications is that the experimental results and the theoretical underpinning strongly complement each other,” says Haverkate.

Chan carried out measurements on the electrolyte material using the neutron diffraction method. This involves sending neutrons through the material. The way in which the neutrons are dispersed makes it possible to deduce certain characteristics of the material, such as the density of protons in the crystals. Haverkate comments satisfyingly, “It is the first time that measurements have been taken of solid-material electrolytes in this way, and on such a small scale. The fact that we had nuclear research technologies at the Reactor Institute Delft at our disposal was tremendously valuable.”

This is just the first step.  The combination of TiO2 and CsHSO4 does not mark the end of the search for a suitable solid-material electrolyte, but does show promising beginning.

Other material combinations will be tested that may achieve better scores in the area of stability.  Professor Fokko Mulder, who is Haverkate’s and Chan’s PhD supervisor, says. “At this stage, we are more concerned about acquiring a fundamental understanding and a useful model, than the concrete issue of finding out what the most suitable material is. It is important that we identify the effect of nanocrystals, and give it a theoretical basis. I think there is great potential for these electrolytes. They also have the extra benefit of continuing to function well over a wide range of temperatures, which is of particular relevance for applying them in fuel cells.”

Maybe the professor is right, but a lot of fuel cells minds are going to be focusing on those two papers from the Delft team.  Some might not wish to wait for theory before tests and trials.  An increased temperature operating range for fuel cells and reduced heat output losses from internal resistance are going to be very welcome improvements.