Nitrogen-Doped Cu2S/MoS2 Heterojunction Nanorod Arrays on Copper Foam for Efficient Hydrogen Evolution Reaction

Graphical His and HER : Nitrogen doped Cu 2 S/MoS 2 heterojunction nanorod arrays grafted on copper foam in situ have been created for efficient hydrogen evolution reaction. The results showed the remarkably improved catalytic activity by designing and tuning the heterostructure, conductivity and active sites. The fabrication of non-noble element electrocatalysts with comparable catalytic activity with Pt-based materials is in great requirements for water splitting to achieve sustainable hydrogen production. Cu 2 S/MoS 2 heterojunction nanorod arrays on copper foam were prepared for this purpose. The nitrogen doping was achieved in situ. HRTEM, SEM, XPS and EDX verified the heterojunction interfacial texture and the defect-rich nanoarray configuration. The heterojunction interfacial texture, the defect rich configuration and the outward active sites optimized the structure required as a high-efficient hydrogen evolution reaction (HER) electrocatalyst. As a result, the charge transfer resistance of the nanoarrays was estimated to be 5.4 Ω at −200 mV versus RHE, even lower than both the precursors. The electrochemical double layer capacitance was 49.95 mF cm −2 , which was higher than both the precursors. The Cu 2 S/MoS 2 heterojunction nanoarrays-like electrocatalyst exhibited significant performance with a low overpotential (91 mV at 10 mA cm −2 ) and a small Tafel slope (41 mV dec −1 ) in alkaline electrolyte with 85.3 % retained ability after 1000 cycle runs. This work paves a road for developing high-performance HER electrocatalysts.