Multiple-Strategy Design of MOF-Derived N, P Co-Doped MoS2 Electrocatalysts Toward Efficient Alkaline Hydrogen Evolution and Overall Water Splitting

The multiple strategy design is crucial for enhancing the efficiency of nonprecious electrocatalysts in hydrogen evolution reaction (HER). In this work, we successfully synthesized N, P-codoped MoS2 nanosheets as highly efficient catalysts by integrating doping effects and phase engineering using a porous metal-organic framework (MOF) template. The electrocatalysts exhibit excellent bifunctional activity and stability in alkaline media. The N, P codoping induces electron redistribution to enhance conductivity and promote the intrinsic activity of the electrocatalysts. It optimizes the H* adsorption free energy and the dissociative adsorption energy, resulting in significant enhancement of HER activity. Moreover, the porous MOF structure exposes a large number of electrochemically active sites and facilitates the diffusion of ions and gases, which improve charge transfer efficiency and structural stability. Specifically, at a current density of 10 mA cm-2, the overpotential of the HER is only 32 mV, with a Tafel slope of 47 mV dec-1 and Faradaic efficiency as high as 98.51% (at 100 mA cm-2). Only a 338 mV overpotential is required to achieve a current density of 50 mA cm-2 for oxygen evolution reaction (OER), and a potential of 1.49 V (at 10 mA cm-2) is sufficient to drive overall water splitting. Further experimental measurements and first-principles calculations evidence that the exceptional performance is primarily attributed to the dual functionality of N and P dopants, which not only activate additional S sites but also initialize the phase transition of 2H to 1T-MoS2 to facilitate the rapid charge transfer. Through in-depth exploration of the combined design of multiple strategies for efficient catalysts, our work paves a new way for the development of future efficient nonprecious metal catalysts.