Strategies for improving performance of iron-based catalysts in activating heterogeneous Fenton-like oxidation in pollutants degradation: From the perspective of materials structure design

Abstract

Various organic pollution is posing serious threat on the sustainable society development. Due to the strong oxidative ability of reactive oxygen species (ROSs), advanced oxidation processes (AOPs) have outperformed as a promising strategy owing to their high efficiency in eliminating organic pollution. As a typical representative, heterogeneous Fenton-like oxidation motivated by hydrogen peroxide (H2O2) activation via iron-based catalysts is attracting much attention because of their superiorities over conventional homogeneous Fenton oxidations. Nevertheless, several challenges need to be tackled for expanding its applications, including low pollutants/oxidant adsorption, low hydroxyl radical (·OH, the main ROS) generation because of slow Fe3+/Fe2+ cycle and limited exposed active sites, limited ROSs utilization, insufficient intermediate diffusion, etc. To address these challenges, various materials construction strategies have been explored in recent years. Herein, based on the reported studies mainly in recent five years, we give an in-depth overview and discussion on these research. Firstly, several newly iron-based heterogeneous Fenton-like oxidation catalysts were briefly introduced. Then, we laid emphasis on various strategies of the materials design and their mechanisms in improving the catalytic performance involving dual reaction center (DRC) and bimetallic catalytic center (BCC) construction, Fe2+ substitution, vacancies introduction, composite, supported, and confined catalysts, and catalysts with synergistic effect. Finally, the possible future research direction and perspective were proposed. It’s expected that this review paper could provide some insight on the design of heterogeneous Fenton-like oxidation catalysts for the relevant researchers.