NITROGEN-ENRICHED CARBON WITH ENCAPSULATED NICKEL NANOPARTICLES FOR HYDROGEN EVOLUTION ELECTROCATALYSIS IN ALKALINE ELECTROLYTES

摘要

A highly efficient hydrogen evolution catalyst in alkaline electrolyte is presented. Herein, we reported the fi rst synthesis of nitrogen-enriched carbon with encapsulated nickel nanoparticles (Ni@NC) through two step pyrolysis of the mixture of nickel acetate and urea. This simple and scalable procedure achieve 21.74% nitrogen doping content on carbon detected by elemental distribution analysis and unique nickel core/carbon shell structure. The non-noble catalyst exhibits a low onset potential (~0.066 V vs reversible hydrogen electrode), high current density (10 mA cm~(-2) with an overpotential of 193 mV), excellent kinetics (Tafel slope of 82 mV dec~(-1)) and a superior stability toward commercial 10% Pt/C in 1 M KOH. Ni@NC is comparable or even superior to state-of-the-art non-noble metal catalysts. The simple, cheap and scalable preparation procedure enables the practical application of the catalyst and also paves a way for the preparation of other nitrogen-enriched carbon-based core/shell materials for practical applications.