Italian scientists however think they have found the answer. They are using inexpensive graphene sheets to storage hydrogen. When they want to release the hydrogen they simply buckle the sheets and shake off the atoms.

According to RSC, “Now, Valentina Tozzini and Vittorio Pellegrini of NEST, the Nanoscience Institute of the Italian National Research Council, and Normal School, have used density functional theory and molecular dynamics simulations to show that distorted sheets of graphene – single layers of carbon atoms in a honeycomb configuration – might provide another approach.

“The team’s calculations suggest that if layers of graphene are compressed laterally to form corrugations, hydrogen would find it energetically favourable to chemically bind to the convex tops of the ridges.”

So, once the hydrogen is bound to the top ridges of the graphene sheets, the trick is to getting them to fall off. The Italian scientists say that buckling a graphene sheet is akin to two people shaking the particles off a dusty carpet or throw rug. By reversing the ridges and applying mechanical force the hydrogen will fly off like dust.

Anyway, this is still in the Italian labs and need more research before prototyping can begin. But, it holds promise that one day soon, hydrogen storage will be cheap, efficient and widely available.

Hydrogen Fuel Tank

One of the aspects that is holding back the growth and commercialization of hydrogen cars and infrastructure development are cheap and effective H2 storage tanks. Hydrogen fuel tanks inside the vehicles tend to be bulky, too heavy and too expensive. Hydrogen storage tanks outside the vehicles such as at H2 fueling stations face the same challenges.

So, the U. S. Department of Energy (DOE) has stepped in and awarded over $7 million total in four smaller contracts in order to tackle the hydrogen storage issue on several different levels using differing kinds of emerging technologies.

The Pacific Northwest National Laboratory, HRL Laboratories, Lawrence Berkeley National Laboratory and the University of Oregon are all receiving contracts of between $1.2 million and $2.1 million dollars to improve upon 4 different types of hydrogen storage tanks.

Pacific Northwest National Laboratory is being paid up to $2.1 million to improve upon the design and manufacture of carbon fiber composite materials that will bring down the costs of these types of compressed hydrogen tanks. HRL Laboratories LLC, is being paid up to $1.2 million to develop hydrogen-rich liquids that can store and release high amounts of hydrogen gas.

The Lawrence Berkeley National Laboratory is being paid up to $2.1 million to develop metal-organic framework materials that can store high quantities of hydrogen. And the University of Oregon is being paid up to $2 million to develop chemical hydrogen storage materials that can be used both onboard and off board hydrogen vehicles.

By reducing the price of hydrogen fuel tanks inside of cars and the price of hydrogen storage tanks at fueling stations and production centers, the total cost of owning a hydrogen car will come down. In addition profits will go up for those selling hydrogen fuel and it is this profit motive that will encourage the building of the needed hydrogen refueling infrastructure in the near future.

Since wind energy is an intermittent power source, it is wise to store the extra energy created when the wind is blowing hard and use this stored up energy when hardly any wind is blowing at all. And by using hydrogen as the storage method, no major supporting infrastructure needs to be built.

Now, once the hydrogen is inside the natural gas pipelines there are several options as to what can be done with the H2 gas blend. The first option is to send this blend to the natural gas fired power plants to help them create electricity more cleanly than ever before and put this electricity back on the grid.

The second option is to send the hydrogen gas blend to homes for cleaner burning in one’s home heating systems, water heaters and gas stoves. On the transportation side, India for the past few years has been developing vehicles than run on hydrogen-natural gas blends inside common CNG vehicles.

If this option were to be taken then the hydrogen and natural gas blend could be piped to the current CNG stations for use in CNG vehicles. Or the hydrogen – CNG blend that is pumped for home use not only could be used to heat the home and for cooking but one could tap into this source and use the hydrogen and natural gas blend in their CNG cars.

Of course another option is to use the pipeline as a carrier for hydrogen and extract the hydrogen from the CNG and use it at the pump for H2 powered cars. The same could be done for homeowners who want their own home hydrogen fueling stations in their garages.

So you see, just getting the renewable hydrogen gas into the natural gas pipelines has many options and benefits. One has to wonder, why didn’t we think of this sooner?

The problem with hydrogen atoms bonding with other elements is that either those bonds are too weak or too strong. If the bonds are too strong then heat is needed to separate the hydrogen atoms from the material. If the bonds are too weak, then there is instability in the storage.

Researchers from China and the U. S. have been using computer modeling to find a material with moderate bonding qualities.

According to Physorg.com, “As the researchers explained, the greatest difficulty in finding a sufficient hydrogen storage material for onboard storage systems lies in meeting multiple requirements with a single material. For example, in previous studies researchers have found that light metal hydrides can store hydrogen with a gravimetric density of 20 wt. %, but the material is not reversible, meaning it cannot be reused. Also, the hydrogen desorbs only at very high temperatures.

“In contrast, other materials such as carbon nanotubes and metal or covalent organic frameworks can store hydrogen reversibly, but the hydrogen adsorbs only at very low temperatures. The difference is due to bonding: in light metal hydrides, hydrogen is held in much stronger bonds than in the second group of materials. The researchers explain that, ideally, hydrogen should be bound with an intermediate binding energy.”

The article goes onto say, “The researchers systematically investigated 10 Pc-based porous sheets with transition metal atoms from scandium (Sc) through zinc (Zn), and found that porous Pc sheets with Sc atoms could store up to 4.6 wt. % hydrogen. In addition to the Sc atoms’ regular distribution in the Pc sheet, Sc has two other attractive features. First, it is lighter than other transition elements, allowing the overall storage material to be relatively light. Second, Sc atoms have a large size, so that they stick out and can capture more hydrogen molecules.”

I’ve talked about hydrogen fuel storage many times in this blog. Both inside and outside an H2 car the efficiency of hydrogen storage needs to go up and the price needs to come down in order for these vehicles and the supporting infrastructure to become commercially viable.

Sometimes I think we are just one small breakthrough away from disrupting the paradigm of fossil fueled vehicles. As long as knowledgeable scientists and researchers keep working the issue from different angles, the solution I believe will happen sooner rather than later.

UTD Researchers

There’s been a lot of research in materials sciences in finding cheaper alternatives in which to store hydrogen or use as catalysts for hydrogen reactions. Most of this breakthrough technology perpetually seems to be 10 to 20 years away before commercialization.

This is why when I heard about what the researchers at the University of Texas, Dallas are doing in regard to titanium-doped aluminum I got a bit excited since this seems to me to be more of a near-term solution rather than a longer term pie-in-the-sky idea.

The UTD researchers noticed that light-weight aluminum hydrides can be made to release its hydrogen bond by slightly increasing the temperature which is an advantage over current metal hydride systems that require more energy in order to release their bonds.

According to UTD graduate student Irinder Singh Chopra, “We investigated a certain class of materials called complex metal hydrides (aluminum-based hydrides) in the hope of finding cheaper and more effective means of activating hydrogen.

“Our research into an aluminum-based catalyst turned out to be much more useful than just designing good storage materials. It has also provided very encouraging results into the possible use of this system as a very cheap and effective alternative to the materials currently used for fuel cells.”

So, let’s think about this statement for a moment. If it is true that titanium-doped aluminum holds the key for both hydrogen storage and as a catalyst in fuel cells, this will bring the price of storage tanks and FC’s way down without giving up any effectiveness. In fact, in the case of storage, hydrogen tanks will be more effective at releasing H2 at lower temperatures. And this, my friend, is a very Big Deal.

Pictured above are UTD researchers Irinder Chopra (left) and Jean-Francois Veyan.

But, there are some scientists who wish to rewrite this standard by working on hydrogen storage tanks that don’t require this much pressure. Researchers in Denmark, for instance, are developing hydrogen fuel tanks that absorb H2 using porous magnesium borohydride.

According to Spectroscopynow.com, “Researchers in Europe have developed a hydrogen storage material based on porous magnesium borohydride that can safely adsorb large quantities of the gas. They used infrared spectroscopy and other techniques to investigate this material. The team, led by Filinchuk and Torben Jensen at the University of Aarhus, in Denmark, developed highly porous magnesium borohydride so that it can store large amounts of hydrogen gas via two distinct mechanisms – chemically bonded hydrogen and physically adsorbed.

“Borohydrides have been investigated previously as hydrogen storage materials and have various advantages and disadvantages as do porous materials in which hydrogen is adsorbed physically but is not incorporated chemically into the storage medium. The researchers state that their material is the first light-metal hydride that is porous like a metal-organic framework (MOF) and is capable of storing molecular hydrogen. The researchers suggest that their porous magnesium borohydride is rather promising in that it can release hydrogen gas at relatively low temperatures but holds on to the gas at a high proportion of the material’s mass, about 3 percent (18-percent of hydrogen, in total).”

Now, I’ve talked about using both magnesium and borohydride in the past for hydrogen storage. I’ve also talked about the mechanical absorption and release of hydrogen in tanks using various methods and materials. What is interesting about this latest discovery is that both processes may be used in conjunction with one another to store and release a higher volume of hydrogen than one method alone.

And if hydrogen fueling tanks based upon porous magnesium borohydride do become the norm in H2 cars and vehicles, this may mean that modifications at the hydrogen fueling stations will need to be made to accommodate the lower pressures needed at the pump.

One of the aspects that have been holding metal hydride tanks back in the past has been the weight of the tanks themselves. So for magnesium borohydride tanks to become a commercial success they will need to be lightweight and strong as well.

Researchers at MIT think they are on the right track by using activated carbon. According to MIT, “The team analyzed the activated carbon’s storage of hydrogen using a technique called inelastic neutron scattering, which they say is uniquely capable of determining whether the hydrogen in the sample exists as individual atoms or H2 molecules. This approach can also assess the gas’s interaction with the storage material.

“Using this method, they were able to provide convincing evidence, for the first time, that hydrogen moves into the material as a result of a phenomenon called the spillover effect, in which atoms – thanks to the presence of platinum particles as a catalyst – split off from their molecules and diffuse through the carbon, where they bond to its surface. Other researchers had suspected the spillover effect was involved, but had been unable to demonstrate that this was the case.”

The one downside is that an expensive platinum catalyst is also currently used in the process. So, future research will be focused on new inexpensive materials to replace platinum in this process which would make such hydrogen storage more commercially feasible.

Nano Blades

Researchers at the Rensselaer Polytechnic Institute (RPI) have discovered that magnesium-based “nano blades” or nano-sized material in the shape of blades could be the next hydrogen storage solution. Some of the advantages of the nano blades is quick storage and release of H2 under low temperatures and the material is recyclable. These are all requirements that the U. S. Department of energy has asked for.

According to RPI, “The scientists created the magnesium-based nanoblades for the first time in 2007. Unlike three-dimensional nanosprings and rods, nanoblades are asymmetric. They are extremely thin in one dimension and wide in another dimension, creating very large surface areas. They also are spread out with up to one micron in between each blade.

“In order to store hydrogen, a large surface area with space in between nanostructures is needed to provide room for the material to expand as more hydrogen atoms are stored. The vast surface area and ultrathin profile of each nanoblade, coupled with the spaces between each blade, could make them ideal for this application …”

The RPI discovery is promising especially the prospect of using nano blades in future hydrogen storage tanks. There are a few bugs to be worked out before commercialization, however. New materials are currently being tested for the nano blades that don’t degrade as quickly as the materials used in this test.

Now that the researchers have a structure that will work, however, it is only a matter of time until the find the right combination of materials with a long lifespan which will be the key to commercialization.

A couple of weeks ago, I talked about how ships contribute more pollutants to the atmosphere worldwide than do cars. These barges and container ships on the high seas burn a cheap, sludgy form of diesel fuel called “bunker oil”.

At that time I suggested an immediate solution was for these ships to switch to burning clean diesel fuel and eventually switch over the hydrogen. Some smaller ships, vessels and boats have done just that.

Take for instance the University of Birmingham fuel cell ferryboat called the Ross Barlow which runs on solar panels, hydrogen fuel cells and battery packs. One of the most interesting parts of the Ross Barlow is its hydrogen storage system, using metal hydrides, which is said to be able to last 100 years. This is longer than the life expectance of the ferryboat.

According to EMPA, “This device can store hydrogen with an energy content of 50 kWh, which is equivalent to 20 pressurized gas cylinders each of 10 Liter capacity. The storage material consists of an alloy of titanium, zirconium, manganese, vanadium and iron in powder form which is packed into sealed steel tubes. The powder absorbs hydrogen, thus acting as a storage medium, only releasing it when heated.

“Since when ‘filling up’ with hydrogen the metal powder generates heat which must be removed, each storage module is located in a water tank which can be warmed or cooled as necessary, In addition the ship is fitted with a solar panel which can supply up to 320 W of electric power.”

So, you see the battle hasn’t been lost in regard to cleaning up the shipping industry. The battle is just beginning. And getting started is one of the most important aspects for hydrogen propulsion technology in regard to planes, trains and automobiles (and this includes ships, too). Can I get an Ahoy on that one? Thank you.

The 9-month project will involve using carbon nanotube reinforcement to replace some of the carbon fiber and epoxy material that some hydrogen fuel tanks currently use. By substituting carbon nanotubes, this will have three advantages.

First. introducing carbon nanotube technology will reduce the overall weight of the hydrogen fuel tanks by 20 to 30-percent. This will result in higher fuel mileage for the vehicle. Second, carbon nanotube technology will provide more strength and durability to the hydrogen fuel tanks.

Third, using carbon nanotubes will drive down the cost of the tanks making hydrogen cars a bit more affordable in the near term. Besides the fuel cell itself, the next costliest part of a hydrogen FCV is generally the fuel tank.

Driving down costs for the most costliest parts of an FCV such as the hydrogen fuel tank will bring down the overall costs and this will lead to another step towards commercialization in the near future.