Nitrogen-doped graphene hydrogel-supported NiPt-CeO_x nanocomposites and their superior catalysis for hydrogen generation from hydrazine at room temperature

The safe and efficient storage and release of hydrogen is one of the key technological challenges for the fuel cell-based hydrogen economy. Hydrazine monohydrate has attracted considerable attention as a safe and convent chemical hydrogen-storage material. Herein, we report the facile synthesis of NiPt-CeO_x nanocomposites supported by three-dimensional nitrogen-doped graphene hydrogels (NGHs) via a simple one-step co-reduction synthesis method. These catalysts were composition-dependent for hydrogen generation from an alkaline solution of hydrazine. (Ni₅Pt₅)₁-(CeO_x)_0.3/NGH exhibited the highest catalytic activity, with 100% hydrogen selectivity and turnover frequencies of 408 h^–1 at 298 K and 3, 064 h^–1 at 323 K. These superior catalytic performances are attributed to the electronic structure of the NiPt centers, which was modified by the electron interaction between NiPt and CeO_x and the strong metal–support interaction between NiPt-CeO_x and the NGH.