Interfacial active sites on Co-Co2C@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-Co2C@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-Co2C@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 center dot mol(-1) during the hydrolysis of NH3BH3. The catalytic stability of Co-Co2C@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-Co2C@C prompts the dissociation of reactants (NH3BH3 and H2O molecules), leading to an enhanced catalytic hydrogen generation from NH3BH3 hydrolysis (Co activates NH3BH3 and Co-C activates H2O). 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.

Automated summary

Design catalysts with interfacial active sites consisting of Co and Co-C on Co-Co2C@carbon heterostructure, which are designed through annealing and high-pressure carbonization, for efficient catalytic hydrogen generation. The operating temperature during the high-pressure carbonization is responsible for the construction and regulation of the Co-Co2C@C heterostructure. The optimal catalyst exhibits high turnover frequency and low activation energy during the hydrolysis of NH3BH3.