Architectured Metal Catalysts for Carbon-Neutral Hydrogen Energy Conversion

Abstract To build a carbon-neutral hydrogen energy society, it is essential to not only produce hydrogen without relying on fossil fuels, but also to develop technologies to convert hydrogen into storable and transportable materials, effectively deliver it to appropriate destination when needed. Furthermore, it is necessary to propose innovative ways to utilize hydrogen beyond its use as an energy source. This account mainly focuses on (1) hydrogen production from renewable energy, (2) carbon dioxide hydrogenation into methane and formic acid (CO2 reduction and hydrogen storage), (3) dehydrogenation of formic acid at low temperatures (hydrogen release), and (4) elucidation of the hydrogen spillover phenomenon and its innovative applications (hydrogen utilization). Based on unique catalyst design strategies, such as organic-inorganic hybrid catalysts, highly controlled metal and alloy nanoparticle catalysts, and self-catalytic reactors fabricated by metal 3D printing, comprehensive technology for converting renewable energy into hydrogen and making effective use of it can be exploited.