The existing means of storing hydrogen are rather costly and energy intensive, H2 either needs to be pressurised at 700 bars, liquified to -252.8 degrees Celsius, or stored using both in proportionate combination. With the prospective increase in hydrogen production and usage, the need for better storage capacity will grow along with the search for alternatives.
An exciting prospective technology has emerged as a potential alternative to store/carry hydrogen utilising nanoparticles.
Figure 1 Nanoparticle structure made of palladium (Green) and iridium (Red) proposed for absorbing hydrogen. Credit: DESY, Andreas Stierle 1
This alternative method for hydrogen storage was investigated by DESY’s Andrea Stierle’s team. They explored storage using palladium particles 1.2 nanometres in diameter (later changed to 1 nanometre in diameter).2 Their detailed research3 was published on the American Chemical Society (ACS) journal, where they observed a range of graphene supported palladium nanocluster structures.
The nanocluster structure they settled on hosts an iridium particle at its core, while palladium particles blanketed the iridium and the whole structure was aided by a graphene support. They found that the palladium is an excellent hydrogen adsorber, and therefore is highly unlikely to penetrate the structure. Upon storing the hydrogen on the palladium cluster surface, it can then be released with minimal heat.
According to DESY article, Stierle would like to find out what storage densities can be achieved through this method. It has also been added that further optimisation of the method could be considered, one of which could be utilising an alternative carbon structure instead of graphene.
DESY’s research may have revealed a new alternative for hydrogen storage. Should storage densities exceed current averages, we could see major benefits. It could improve and expand the uses of hydrogen both within and outside the transport and energy sector, unburden an energy sector of storage limitations and requirements, and push forth innovation opening up new applications of hydrogen.