Wettability and heterojunction synergistic interface optimization guided Co doped MoS2/Ni3S2-GO/NF catalytic electrode to boost overall water splitting.

Rationally designing cost-efficient, high-activity and durable electrocatalysts are used for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is sense to solve the energy crisis and conversion. Herein, the heterostructure superwetting Co–MoS 2 /Ni 3 S 2 -GO/NF electrode is successfully fabricated by a typical hydrothermal reaction and it's electrocatalytic performance is also systematically studied. Thanks to the establishment of Co doped MoS 2 /Ni 3 S 2 heterojunction, the improvement conductivity by the addition of graphene oxide (GO), and the superhydrophilicity and superaerophobicity of microstructure, the electrode shows excellent catalytic characteristics and only need an overpotential of 123 mV for OER and 161 mV for HER to reach 10 mA cm−2 and can work steadily for 15 h in alkaline solution. Remarkebly, the superwetting heterojunction electrode demonstrated excellent overall water decomposition ability when used as bifunctional electrocatalyst in 1.0 M KOH and only 1.47 V is required to achieve 10 mA cm−2. Density functional theory (DFT) calculations show the constructed heterogeneous interface and Co doping are conducive to optimizing the chemisorption energy of hydrogen-containing intermediates. This work provides a new way of thinking that collaborative optimization of electrode structure and surface wettability regulation to increase the active area of reaction and accelerate the bubble release toward high-performance OER and HER electrodes. [Display omitted] • The heterojunction structure Co–MoS 2 /Ni 3 S 2 -GO/NF electrode can be prepared by simple hydrothermal method. • The electrode has superhydrophilicity and underwater superaerophobicity. • The electrode has excellent electrochemical performance and stability. • DFT calculation is used to analyze the efficient catalytic mechanism of the electrode. [ABSTRACT FROM AUTHOR]