Hydrogen generation enhanced by nano-forest structures. Issue 16 (3rd February 2016) - Seo, Keumyoung
Abstract : A hierarchical structure of one-dimensional CeO2 /SnO2 core–shell nanowires on a three-dimensional porous disk (namely the "nanowire forest") could maximize the reaction surface area and avoid coarsening during hydrogen generation. Abstract : In the ongoing attempts to alleviate current energy constraints, hydrogen gas, H2, is drawing much attention as an alternative energy storage medium to address the issues of limited energy resources as well as air pollution associated with conventional energy technologies. Here we report H2 generation by thermochemical water-splitting employing a hierarchical CeO2 nanostructure which allows for maximizing the reaction surface area and enhanced H2 generation at relatively low temperatures (800 °C or below). More importantly the nanostructure retains the surface area during H2 generation. The large surface area of the nanostructure was achieved by growing one-dimensional CeO2 /SnO2 core–shell nanowires on a three-dimensional porous disk. Namely the three-dimensional core–shell "nanowire-forest" has increased H2 generation by 45.5% at 800 °C, in comparison to conventional CeO2 thin-film-coated disks used as a reference. Furthermore the total amount of H2 generated by the nanowire forest over one thermal cycle is greater than that of the previously reported values. We believe that such hierarchical CeO2 nanostructures offers a highly effective means for producing H2 gas as well as for other catalytic reactions.