Schottky barrier engineering via coordination chemistry: A pathway to advanced photocatalytic VOC mineralization

Abstract

Photocatalytic oxidation (PCO) has emerged as a sustainable and efficient strategy for the degradation of volatile organic compounds (VOCs). To overcome its inherent limitations in charge separation and visible-light utilization, Schottky junctions are considered an effective solution, with their effectiveness being directly rooted in the quality of the interface. This interface, formed between metal nanoparticles and a semiconductor, is fundamentally dictated by coordination chemistry, specifically the metal-support interaction (MSI). The MSI involves the coordination bonding between metal active sites and specific surface species (like oxygen vacancies or hydroxyl groups) on the semiconductor to form the Schottky barrier. This review provides a comprehensive assessment of both plasmonic and non-plasmonic Schottky junctions applied to VOC remediation by examining the coordination-driven charge transfer mechanisms and by classifying recent advances in materials design. Key performance metrics are also benchmarked across different VOC types (e.g., benzene, toluene, and formaldehyde) and under various operating conditions. Emphasis is placed on the precise role of coordination chemistry in dictating the Schottky barrier height, charge carrier separation efficiency, and subsequent oxygen activation/selectivity toward complete mineralization. Through this critical synthesis, we aim to illuminate the practical and theoretical frontiers of Schottky junction photocatalysts for advanced remediation technologies.