The exploration of efficient nonprecious metal eletrocatalysis of the hydrogen evolution reaction (HER) is an extraordinary challenge for future applications in sustainable energy conversion. The family of first-row-transition-metal dichalcogenides has received a small amount of research, including the active site and dynamics, relative to their extraordinary potential. In response, we developed a strategy to achieve synergistically active sites and dynamic regulation in first-row-transition-metal dichalcogenides by the heterogeneous spin states incorporated in this work. Specifically, taking the metallic Mn-doped pyrite CoSe2 as a self-adaptived, subtle atomic arrangement distortion to provide additional active edge sites for HER will occur in the CoSe2 atomic layers with Mn incorporated into the primitive lattice, which is visually verified by HRTEM. Synergistically, the density functional theory simulation results reveal that the Mn incorporation lowers the kinetic energy barrier by promoting H-H bond formation on two adjacently adsorbed H atoms, benefiting H2 gas evolution. As a result, the Mn-doped CoSe2 ultrathin nanosheets possess useful HER properties with a low overpotential of 174 mV, an unexpectedly small Tafel slope of 36 mV/dec, and a larger exchange current density of 68.3 μA cm(-2). Moreover, the original concept of coordinated regulation presented in this work can broaden horizons and provide new dimensions in the design of newly highly efficient catalysts for hydrogen evolution.

Development of efficient and affordable electrocatalysts in neutral solutions is paramount importance for the renewable energy. Herein, we report that the oxygen evolution reaction (OER) performance of Co3 S4 under neutral conditions can be enhanced by exposed octahedral planes and self-adapted spin states in atomically thin nanosheets. A HAADF image clearly confirmed that the active octahedra with Jahn-Teller distortions were exposed exclusively. Most importantly, in the atomically thin nanosheets, the spin states of Co(3+) in the octahedral self-adapt from low-spin to high-spin states. As a result, the synergistic effect endow the Co3 S4 nanosheets with superior OER performance, with exceptional low onset overpotentials of circa 0.31 V in neutral solutions, which is state-of-the-art among inorganic non-noble metal compounds.

Electrocatalytic water splitting, which underpins a series of sustainable energy conversion technologies, has become even more relevant as our energy needs have increased. Exploring efficient non-precious-metal electrocatalysts is necessary for the widespread application of this energy storage model. Twodimensional (2D) ultrathin solids with a special atomic and electronic structure are full of unlimited potential in the pursuit of high-efficiency electrocatalysts and have been identified as a perfect platform for establishing clear structureproperty relationships. Hence, in this review, we first clear up the fundamental relationship between intrinsic charge and spin ordering and electrocatalytic properties. Then, on this basis, we summarize recent attempts to regulate electrical behavior and spin ordering in 2D ultrathin solids to optimize electrocatalytic water-splitting performance. In addition, we highlight the coupling relationship among lattice, charge, and spin ordering in ultrathin electrocatalysts. Finally, we also present some personal perspectives on the challenges and future research directions in this promising area.