Metal–organic frameworks: classifications, synthesis, structure–property–performance relationship, and techno-economic analysis of redox flow batteries†

Abstract

Metal–Organic Frameworks (MOFs), which are highly porous materials, offer significant potential across multiple energy storage domains, notably within redox flow batteries (RFBs). Over the past decade, MOFs have garnered increasing attention as advanced electrode and separator materials in RFBs, driven by their intrinsic porosity, tunable architecture, and multifunctional design potential. Prior to discussing MOFs in RFBs, it is important to examine their classification, nomenclature and key properties including their synthesis methodologies across diverse MOF types, as these factors play a vital role in developing efficient RFBs. To date, various metal ions and linkers have been utilized in MOF synthesis, and their selection influences the resulting framework. Correspondingly, a structure–property–performance relationship has been established to correlate the material's properties with its electrochemical performances. We further examined their utilization in RFBs' membranes in a separate section. Additionally, we discuss the challenges and opportunities associated with MOF-based electrodes and membranes. Moreover, special focus is also given to techno-economic analysis for the practical implementation of RFBs. This discussion reveals the potential pathways for advancing MOFs in energy storage applications.