Recent advances in 2D transition metal compounds for electrocatalytic full water splitting in neutral media

Water electrolysis in neutral media has attracted concerted research efforts because of its practical applications including microbial electrolysis of wastewater and large-scale hydrogen generation by direct electrolysis of seawater. Because the corrosion of electrochemical devices is effectively reduced in neutral environments, the associated cost is consequently lowered. In this context, two-dimensional transition metal compounds have enjoyed extensive applications in the field of renewable energy because of their abundant storage capacity, easily regulated electronic structure, and unique physical and chemical features. As such, this review summarizes recent advances in the use of two-dimensional transition metal compounds as hydrogen evolution, oxygen evolution, and bifunctional catalysts for neutral water splitting. Some engineering strategies to enhance electrocatalytic performances are also discussed. Finally, the current challenges and future opportunities in bifunctional electrocatalysts for full water splitting are presented.