Inter-atomic electronic interactions enabled by a Rh single atoms/CuCo2S4@MoS2 core-shell heterostructure for high-efficiency solar-assisted water splitting

In this work, we developed an electrocatalyst of Rh single atom-confined CuCo2S4@MoS2 core-shell heterostructure (Rh SAs/CuCo2S4@MoS2) for the cathodic hydrogen evolution reaction (HER) and anodic oxygen evolution reaction (OER). Interatomic electronic interaction between Rh single atoms and the CuCo2S4@MoS2 heterostructure allows the improvement of the intrinsic catalytic behavior of each active site. In addition, the Rh SAs/CuCo2S4@MoS2 catalyst combines all advantages of the Rh single atom centers, the uniform core-shell structure of CuCo2S4@MoS2 nanorods, and the open three-dimensional configuration of nickel foam, which significantly enhance the electroactive surface area to expose more active sites, accompanied by excellent capability in charge and mass transportations. As a result, to achieve a current density of 10 mA cm(-2), the device using Rh SAs/CuCo2S4@MoS2(+,-) requires a cell voltage of 1.589 V, along with a high STH conversion efficiency of 19.12%. The high catalytic activities for all the HER, OER, and solar-assisted overall water splitting processes evidenced that Rh SAs/CuCo2S4@MoS2 is a potential electrocatalyst for green hydrogen production.