Self-supported cobalt–molybdenum oxide nanosheet clusters as efficient electrocatalysts for hydrogen evolution reaction

In this paper, we report the three-dimensional self-supported CoMoO4 nanosheet clusters on the nickel foam (denoted as CoMoO4/NF) by a facile hydrothermal-calcination method for efficient hydrogen generation. As a result, the freestanding CoMoO4 electrode exhibits an efficient electrochemical activity towards hydrogen evolution reaction, showing overpotentials as low as 68 and 178 mV at current densities of 10 and 100 mA cm−2 in the alkaline condition (1 M KOH), respectively, a Tafel slope value of 82 mV per decade. Moreover, the electrode exhibits remarkable electrochemical durability for 1000 cycles. Significantly, the water splitting electrolyzer assembled with CoMoO4/NF || NiFe LDH/NF (the nickel iron layered double hydroxide supported on the nickel foam) system achieved 20 mA cm−2 at 1.63 V, showing the CoMoO4/NF is promising for practical water splitting applications.