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[Display omitted] • Fundamental knowledge on SSPFR are detailed illustrated. • Catalytic mechanism of each step and development of SSPFR are reviewed. • Various strategies aimed at improving the reaction rate are discussed and summarized. • Applications are introduced. • Prospects for the future development of SSPFR are presented. Fenton reaction has gained tremendous attention in the field of non-selective pollutant degradation, as •OH with powerful oxidizing capacity can be produced via H 2 O 2 activation. However, the widespread application is limited by the continuous consumption of commercial H 2 O 2 with high price. As an alternative strategy, self-sufficient photo-Fenton reaction (SSPFR) has been explored, where oxidant H 2 O 2 was in-situ produced inside the system for subsequent Fenton reactions, rather than external addition. Benefiting from the low cost, high H 2 O 2 utilization efficiency, and low risk in H 2 O 2 storage and transportation, SSPFR became a hotpot in scientific research, and developed rapidly in recent years. Herein, we critically reviewed the state-of-the-art development of SSPFR, in which the fundamental mechanism and catalytic process were firstly introduced. Then, SSPFR reaction was divided into three cascade steps: in-situ H 2 O 2 production, H 2 O 2 activation, and reactive oxygen species utilization. This paper reviewed the research progress in every step, and proposes corresponding potential strategies to accelerate the reaction rate. Finally, conclusions and prospects of SSPFR for the removal of organic pollutants were proposed. This study provides a valuable resource for researchers to construct novel and efficient SSPFR systems. [ABSTRACT FROM AUTHOR]

Yolk@shell nanoreactor with coordinately unsaturated metal sites on Prussian blue analogue nanocubes surface inside the polypyrrole capsule was prepared, in which improving catalytic activity and lowering metal leaching were simultaneously realized. [Display omitted] • Improving activity and lowering leaching are simultaneously realized in nanoreactor. • Nanoreactor show high PMS utilization efficiency and TC mineralization efficiency. • PMS activation is encouraged via Lewis acid-base reaction on CUMSs. • SO 4 − converts to OH and then to 1O 2 inside nanoreactor under confinement effect. • Metal leaching is suppressed under the protection of compacted PPy shell. In peroxymonosulfate (PMS)-based Fenton-like reaction, there was an irreconcilable contradiction between improving the catalytic activity and lowering the metal leaching, since the more catalytic sites exposed, the better activity and the easier leaching. In this work, we have provided a feasible method to address this problem by preparing yolk@shell structure with coordinately unsaturated metal sites on Prussian blue analogue (CUMSs-PBA) nanocubes surface inside the polypyrrole (PPy) capsule. On CUMSs-PBA surface, a large amount of metal sites were exposed and functioned as Lewis acid. As Lewis base, PMS adsorption and activation were encouraged via Lewis acid-base reaction, leading to an enhanced activation efficiency. PMS and pollutants were confined inside the yolk@shell nanoreactor with a limited cavity space, leading to an ultra-high concentration and accelerated degradation rate. In this case, the PMS activation path was altered, and the contributions of OH and 1O 2 were largely improved in comparison with SO 4 −. Generally, the metal leaching was worsened due to the lack of ligand protection on coordinately unsaturated metal sites. Fortunately, the PPy shell was compacted and the pore size on shell was narrowed during the heat-treatment, resulting in the suppression effect on outward diffusion of leached metal ions. Therefore, improving catalytic activity and lowering metal leaching were simultaneously realized in the CUMSs-PBA@PPy nanoreactor. [ABSTRACT FROM AUTHOR]