Interfacial active sites on Co-Co 2 C@carbon heterostructure for enhanced catalytic hydrogen generation

Designing catalysts with capable dual-active sites to drive catalytic hydrogen generation is necessary for the future hydrogen economy. Herein, the interfacial active sites consisting of Co and Co-C on Co-Co 2 C@carbon heterostructure are designed through annealing and high-pressure carbonization. The operating temperature during the high-pressure carbonization under a CO-reducing environment is responsible for the construction and regulation of Co-Co 2 C@C heterostructure. The optimal catalyst has a high turnover frequency (TOF) of 33.1 min −1 and low activation energy ( E a ) of 27.3 kJ·mol –1 during the hydrolysis of NH 3 BH 3 . The catalytic stability of Co-Co 2 C@C has no dramatic deterioration even after 5 cyclic usages. The interfacial active sites and the carbon on the catalyst surface enhance hydrogen generation kinetics and catalytic stability. The construction of interfacial active sites in Co-Co 2 C@C prompts the dissociation of reactants (NH 3 BH 3 and H 2 O molecules), leading to an enhanced catalytic hydrogen generation from NH 3 BH 3 hydrolysis (Co activates NH 3 BH 3 and Co-C activates H 2 O). The construction of hetero-structural catalysts provides theoretical direction for the rational design of advanced transition metal carbide materials in the field of energy catalysis and conversion. Graphical abstract