Sulfur-modified MOFs as efficient electrocatalysts for overall water splitting

In order to alleviate the shortage of fossil energy, it is an effective way to explore superior electrocatalysts for overall water splitting (OWS) to obtain hydrogen energy. Metal–organic frameworks (MOFs) and their derivatives have become one of the most promising candidates for OWS due to their diversified chemical composition, high specific surface area and porosity, accessible catalytic sites as well as adjustable electronic structure. The synthesis of modified conductive MOFs such as sulfur-modified MOFs and corresponding derivatives could accelerate the multi-electron transfer and reduce the energy barrier during the catalytic process. In this review, the common MOF precursors and the mechanism of water splitting including oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) are briefly introduced. More importantly, we aim to elaborate recent advances related to sulfur-modified MOFs which have been incorporated sulfur-containing modifiers such as metal sulfides and sulfur-functionalized ligands. The classification, advantages and synthetic strategies of modified MOFs are in focus. Finally, the application prospect and potential challenges of sulfur-modified MOFs as efficient electrocatalysts are summarized.