The lead‐free halide perovskite A₃Sb₂Br₉ is utilized as a photocatalyst for the first time for C(sp³)−H bond activation. A₃Sb₂Br₉ nanoparticles (A₃Sb₂Br₉ NPs) with different ratios of Cs and CH₃NH₃ (MA) show different photocatalytic activities for toluene oxidation and the photocatalytic performance is enhanced when increasing the amount of Cs. The octahedron distortion caused by A‐site cations can change the electronic properties of X‐site ions and further affect the electron transfer from toluene molecules to Br sites. After the regulation of A‐site cations, the photocatalytic activity is higher with A₃Sb₂Br₉ NPs than that with classic photocatalysts (TiO₂, WO₃, and CdS). The main active species involved in photocatalytic oxidation of toluene are photogenerated holes (h⁺) and superoxide anions (^.O₂⁻). The octahedron distortion by A‐site cations affecting photocatalytic activity remains unique and is also a step forward for understanding more about halide‐perovskite‐based photocatalysis. The relationship between octahedron distortion and photocatalysis can also guide the design of new photocatalytic systems involving other halide perovskites.

中文翻译：

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揭示无铅A3 Sb2 Br9钙钛矿在光催化C（sp3）-H键活化中的A-位效应。

无铅卤化物钙钛矿A ₃ Sb ₂ Br ₉首次用作C（sp ³）-H键活化的光催化剂。具有不同Cs和CH ₃ NH ₃比的A ₃ Sb ₂ Br ₉纳米颗粒（A ₃ Sb ₂ Br ₉ NPs）（MA）显示出对甲苯氧化的不同光催化活性，并且当增加Cs的量时，光催化性能增强。由A位阳离子引起的八面体畸变会改变X位离子的电子性质，并进一步影响电子从甲苯分子到Br位的转移。在调节A-位阳离子后，A ₃ Sb ₂ Br ₉ NPs的光催化活性比经典光催化剂（TiO ₂，WO ₃和CdS）高。涉及甲苯的光催化氧化的主要活性种光生空穴（h ⁺）和超氧阴离子（^。 Ò ₂ ^-）。影响光催化活性的A位阳离子引起的八面体畸变仍然是独特的，也是向更多了解基于卤化钙钛矿的光催化迈进的一步。八面体变形与光催化之间的关系也可以指导涉及其他卤化物钙钛矿的新光催化系统的设计。