A combination of Graphene and Hexagonal Boron Nitride (hBN) can enable hydrogen to be harvested directly from air. Used as membrane with an electrical current this combination may be the next step for fuel cell design.
Theoretically this would allow fuel cells to harvest the hydrogen they need to function directly from the air removing the need to manually add additional water fuel to the batteries. This could result in a very long life fuel cell. In combination with solar panels whit could provide a simple method for transforming energy from the environment in the form of sunlight and air to a sustainable power supply. Scaled up this may become an important contributor to the issue of night time power supply.
There is the slight issue of requiring a power source to allow the hydrogen to split from the water molecules. The researchers suggest that fuel cells can be used as the power source to enable a completely fuel cell based power system that extracts energy from the air. According to the report the combination of Graphene and hBN enables a more efficient water splitting process. The key to this efficiency gain appears to be the specific combination and the addition of catalytic nano particles such as platinum. This combination apparently out performs all other existing combinations on the market.
If it is truly more efficient then it could allow fuel cells to compete on price with solar + batteries or become a part of a solar + fuel cell hybrid system. So instead of using sunlight to charge your batteries while your car is parked at the mall use it to power your fuel cells so they can extract energy from the air around.
Just a slight problem is that the amount of energy required to split hydrogen from it’s watery bonds is equivalent to the amount of energy that is gained from hydrogen. Hence it is a bit of an accounting trick to say that the combination is more efficient. Really it is more efficient than other combinations but it is not changing the laws of physics to enable hydrogen to be split from water molecules more efficiently than any other method. It simply takes a specific amount of energy to achieve this goal. Like lifting weights to move an object with a specific mass takes a specific amount of force. There are many ways to achieve the required amount of force but there is currently no way to use less force to move the object. Splitting hydrogen from water requires a certain amount of energy and provides the same amount of energy that was used to split it.
Storing hydrogen is very tricky as the atoms are the smallest of all atoms so they cannot be easily contained. Graphene does provide a solution to that problem as hydrogen atoms are blocked by the very dense electron cloud that the structure of graphene enables. A combination of graphene+hBN fuel cells and graphene containers may enable us to bootstrap the hydrogen economy. At some point though we need to spend some energy to get the hydrogen into a useable form. The majority of the worlds hydrogen currently produced is a by product of the petroleum refining process. That is not sustainable so at some point we have to find a method of generating hydrogen that does not absorb electricity from the grid. With fossil fuels in rapid decline this process is likely to be a difficult nut to crack.
In the meantime we can continue to build out wind+solar and over time we will be able to move away from the intrinsically dangerous and destructive energy supply that currently dominates. The future looks bright for sustainable energy solutions.