Co4S3 grafted 1 T-phase dominated WS2 ultrathin nanosheet arrays for highly efficient overall water splitting in alkaline media

Developing the earth-abundant transition metal-based bifunctional electrocatalysts for water splitting and renewable energy devices has attracted much attention. Herein, we report a 1 T-WS 2 in ultrathin nanosheet arrays grafted with Co 4 S 3 on conductive carbon cloth (CC) (1 T-Co 4 S 3 -WS 2 /CC) through a feasible in-situ growth and vulcanization. The optimized 1 T-Co 4 S 3 -WS 2 /CC catalyst exhibits an impressive electrocatalytic activity and remarkable stability with the oxygen/hydrogen evolution reaction (OER/HER: 278/75 mV for 10 mA cm −2 ). It also showed the small Tafel slope values of 61.7 and 58.4 mV dec −1 , respectively. Additionally, the 1 T-Co 4 S 3 -WS 2 /CC (−/+) achieved 1.59 V@10 mA cm −2 in alkaline media superior to the most previously reported non-precious metal electrocatalysts. The outstanding performance could be attributed to the synergy between heterostructures of Co 4 S 3 and 1 T-WS 2 modifying the electronic structure to accelerate water splitting kinetics. Thus, this work presents a rational design of scalable, high-efficiency, stable water splitting electrocatalysts based on WS 2 .