A NiCo/NiO–CoOx ultrathin layered catalyst with strong basic sites for high-performance H2 generation from hydrous hydrazine

Abstract

The exploration of non-noble-metal recyclable catalysts for high efficiency H₂ generation from N₂H₄·H₂O is of great significance for the sustainable strategy of society. A NiCo/NiO–CoO_x ultrathin layered catalyst was fabricated successfully via a dynamics controlling coprecipitation–reduction (DCCR) process followed by calcination and applied to H₂ generation from N₂H₄·H₂O. Small nanosized NiCo particles (∼4 nm) were uniformly anchored on the surface of the NiO–CoO_x ultrathin layered supports. Based on the cooperation between the NiCo active-centers and high intensity base-sites of the NiO–CoO_x support, the Ni₇₀Co₃₀/NiO–CoO_x ultrathin layered nanocomposite exhibits over 99% selectivity for H₂ generation from N₂H₄·H₂O with a high reaction rate (mol_N2H4 mol_NiCo⁻¹ h⁻¹) of 5.49 h⁻¹ without using alkali as a catalyst promoter at 25 °C, which is superior to the reported studies. Moreover, the NiCo nanoalloys loading on the NiO–CoO_x sheets enables an outstanding recycle performance over 10 cycles. The non-noble-metal NiCo/NiO–CoO_x layered nanocomposite shows great value in catalyzing H₂ generation from N₂H₄·H₂O in practical applications.