Myrica rubra-like P–Co1-xS/C as an efficient catalyst for all-pH hydrogen evolution reaction

Abstract

The development of cheap, efficient and stable hydrogen-producing catalysts is the current research focus, especially the catalysts that can work stably in the whole pH range. In this work, a myrica rubra-like structure of P–Co_1-xS/C was synthesized by hydrothermal reaction, sulfurization and phosphorization using spherical flower-like cobalt glycerate (CoG) as precursor. The design of this multilevel structure of P–Co_1-xS/C effectively increases the specific surface area. The doping phosphorus and the protection of carbon layer greatly improve catalytic performance and enhance the stability of Co_1-xS in the hydrogen evolution reaction (HER) at full pH range. When the current density is 10 mA cm⁻², the HER overpotentials of P–Co_1-xS/C in acidic, alkaline and neutral solutions are 86, 93 and 167 mV, and respectively. The Tafel slopes of P–Co_1-xS/C in acidic, alkaline and neutral solutions are 82, 100 and 103 mV dec⁻¹, respectively. In addition, the electrocatalyst also displays excellent electrochemical long-term stability. After 2000 cycles or 20 h long-term testing, its catalytic activity remains stable without obvious decrease at full pH range.