Rational design and synthesis of advanced metal-organic frameworks for electrocatalytic water splitting

As a promising and significant technology for hydrogen production, electrocatalytic water splitting is a research hotspot in the energy conversion field for alleviating the global energy crisis and achieving carbon neutrality goals. Metal-organic frameworks (MOFs) have been widely investigated as catalyst candidates with remarkable activity and long-term electrocatalysis durability owing to their precise and tailorable structures: tunable pore channels in the range of micropore/mesopore promote the mass/electron transfer; high specific surface areas expose abundant active species; modified metal nodes can serve as active sites; versatile organic ligands can be functionalized to further enhance the electrocatalytic activity. In this review, recent advances in the rational design and synthesis of advanced MOF electrocatalysts for water splitting are presented in the following aspects. First, we analyze the design concepts of MOF electrocatalysts from the perspective of their distinct and modifiable structures Second, three common synthesis techniques of MOF electrocatalysts are briefly introduced. Third, we focus on the classification of different MOFs for robust electrocatalytic water splitting, including pristine MOFs, mixed-metallic MOFs, MOF nanosheets, electrically conductive MOFs, MOFs on substrates, and polyoxometalate-based MOFs Finally, summary and outlook are proposed to uncover the next generation of advanced MOFs for electrochemical energy conversion applications.