A Novel C Doped MoS2/CoP/MoO2 Ternary Heterostructure Nanoflower for Hydrogen Evolution Reaction at Wide pH Range and Efficient Overall Water Splitting in Alkaline Media

Abstract The development of low‐cost and high‐efficiency bifunctional catalysts is still a challenge for hydrogen production through overall water splitting. This paper reports the in‐situ synthesis of C‐doped MoS 2 /CoP/MoO 2 using bacterial cellulose (BC) as the reducing agent and the source of C and using BC (MoS 2 /Co 1.2 MoO 4.2 ⋅ 1.2H 2 O/BC) as the template. Heterogeneous structure for hydrogen evolution reaction (HER) and alkaline water electrolysis in a wide pH range. Due to the large number of defect sites caused by C doping and the synergy between these three active components (MoS 2 , CoP and MoO 2 ), the HER and oxygen evolution reaction (OER) activities of the catalyst have been greatly improved. Therefore, during HER, a small initial overpotential (27 mV) was achieved in 1.0 M KOH. In 0.5 M H 2 SO 4 , 0.1 M PBS and 1.0 M KOH, the current density reached 10 mA cm −2 at overpotentials of 123.4, 150, and 139 mV, respectively. For OER, an overpotential of 268 mV was required to achieve 10 mA cm −2 . The alkaline two‐electrode device composed of C doped MoS 2 /CoP/MoO 2 delivers 10 mA cm −2 at a low potential of 1.51 V and can be easily driven by a single AA battery. This work provides a new design strategy of C doped ternary heterostructures for electrocatalysis and related energy applications.