Defect engineering is a promising strategy to improve the efficiency of persulfate based advanced oxidation processes. Different from previous reports on oxygen vacancy containing catalysts, an iodine vacancy rich material is found highly active in persulfate activation and organic degradation. The Bi₇O₉I₃ with abundant iodine vacancies is synthesized by solvothermal method, and exhibits superior catalytic performance for peroxydisulfate (PDS) activation, with 90% phenol degradation in 60 min. Furthermore, the catalytic activity of Bi₇O₉I₃ can be enhanced by increasing iodine vacancies through calcination below the phase transition temperature or reduction of the iodine dosage in the source materials. The electron paramagnetic resonance spectra, electrochemical measurements, and quenching tests suggest that PDS activation by the iodine vacancy rich Bi₇O₉I₃ is a non-radical pathway. Moreover, the presence of iodine vacancies can not only increase the carrier density to boost the electron transfer capacity of the catalysts, but also lower the Bi valence to enable its role in donating electrons to PDS and receiving electrons from organic substrates. This study provides a new iodine vacancy engineered strategy for PDS activation and non-radical oxidation, and brings insights for defects induced active sites both in materials and vacancy types.

缺陷工程是提高基于过硫酸盐的先进氧化工艺效率的一种有前途的策略。与先前关于含氧空位的催化剂的报道不同，发现富含碘空位的材料在过硫酸盐活化和有机降解中具有很高的活性。溶剂热法合成了碘空位丰富的Bi ₇ O ₉ I ₃，对过氧二硫酸盐（PDS）的活化表现出优异的催化性能，在60分钟内苯酚的降解率为90％。此外，Bi ₇ O ₉ I ₃的催化活性通过在相变温度以下进行煅烧来增加碘空位，或减少原料中的碘剂量，可以提高碘的含量。电子顺磁共振谱，电化学测量和淬火测试表明，富碘空位的Bi ₇ O ₉ I ₃激活了PDS。是非激进的途径。此外，碘空位的存在不仅可以增加载流子密度以提高催化剂的电子转移能力，而且可以降低Bi价以使其在将电子提供给PDS和从有机基质接收电子中发挥作用。这项研究为PDS活化和非自由基氧化提供了一种新的碘空位工程化策略，并为缺陷诱发的材料和空位类型中的活性位点提供了见识。