Metal–organic framework (MOF) based materials: promising candidates for electrocatalytic seawater splitting

Abstract

Electrochemical water splitting typically relies on freshwater, a scarce resource in many regions, limiting its industrial scalability. In contrast, seawater represents an abundant and underutilized source, comprising 97% of the world's total water supply. Electrocatalytic seawater splitting (ESS) thus emerges as a promising method for generating clean hydrogen (H₂) fuel. However, a significant challenge in seawater splitting lies in the electro-oxidation of dissolved ions at the anode, which leads to severe electrode corrosion and competes with the oxygen evolution reaction (OER), thereby reducing its efficiency. Despite the utilization of various electrocatalysts, achieving high current densities for seawater splitting without side reactions remains a formidable task. Recent literature has seen a surge in research focusing on transition metal-based catalysts for this purpose. Metal–organic frameworks (MOFs) have garnered attention in electrocatalysis due to their unique properties, although their application in seawater electrolysis is relatively new compared to alkaline water splitting. To date, numerous studies have been published on MOFs and MOF-based materials for electrocatalytic seawater splitting. However, there is a lack of comprehensive articles summarizing these advancements. This article aims to address this gap by providing an overview of recent progress on MOFs and MOF-based materials tailored specifically for seawater electrolysis. We systematically discuss the relationships between structure, properties, and performance of various MOFs and MOF-based materials, supported by notable examples from recent research. Additionally, we examine how the structural characteristics, morphology, and electronic properties of MOFs influence their effectiveness in seawater electrolysis. Furthermore, the article explores future opportunities and challenges in the field, offering insights into the prospects and obstacles associated with advancing and implementing MOFs and MOF-based materials for seawater electrolysis.