2D/2D-Ni–Co–B/rGO Nanolayers Prepared by Galvanic Replacement for Hydrogen Generation through NaBH<sub>4</sub> Hydrolysis
Mengtian Shi, Yongjiang Hou, Xiaohan Du, Jie Guo, Bo Li, Yixuan Li
Abstract
While non-precious metals like Co and Ni have shown good performance in generating hydrogen from NaBH 4, the challenges of catalyst agglomeration and deactivation have become a focus of future research. To address this issue, in this study, Co nanoparticles on graphene carriers and controllably replaced with nickel atoms to form highly dispersed two-dimensional (2D)/2D Ni–Co nanolayers by Galvanic Replacement Reaction were prepared. Characterization analyses (transmission electron microscope (TEM), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and hydrogen temperature-programmed desorption (H 2 TPD)) suggested that 2D/2D Ni–Co nanolayer catalysts were observed with ultrathin nanolayer structures after using graphene as a carrier. In the hydrogen generation process, the Ni atoms as the main active centers, combined with the synergistic effect of Co and the good conductivity of graphene, contribute to improved hydrogen release. The 2D material showed good hydrogen generation performance, with a rate of 4300 mL·(min·g) −1, maintenance of 94% hydrogen generating activity after five cycles, and lower activation energy of 29 kJ·mol –1 .