Vanadium-based metal-organic frameworks and their derivatives for electrochemical energy conversion and storage

With the excessive consumption of nonrenewable resources,the exploration of effective and durable materials is highly sought after in the field of sustainable energy conversion and storage system.In this aspect,metalorganic frameworks(MOFs)are a new class of crystalline porous organicinorganic hybrid materials.MOFs have recently been gaining traction in energy-related fields.Owing to the coordination flexibility and multiple accessible oxidation states of vanadium ions or clusters,vanadium-MOFs(V-MOFs)possess unique structural characteristics and satisfactory electrochemical properties.Furthermore,V-MOFs-derived materials also exhibit superior electrical conductivity and stability when used as electrocatalysts and electrode materials.This review summarizes the research progress of V-MOFs(inclusive of pristine V-MOFs,V/M-MOFs,and POVbased MOFs)and their derivatives(vanadium oxides,carbon-coated vanadium oxide,vanadium phosphate,vanadate,and other vanadium doped nanomaterials)in electrochemical energy conversion(water splitting,oxygen reduction reaction)and energy storage(supercapacitor,rechargeable battery).Future possibilities and challenges for V-MOFs and their derivatives in terms of design and synthesis are discussed.Lastly,their applications in energy-related fields are also highlighted.