Photoreduction of carbon dioxide (CO₂) into fuels presents a promising approach to mitigate global warming and energy crises. Halide perovskite nanocrystals (NCs) with prominent optoelectronic properties have triggered substantial attention as photocatalysts but are limited by the charge recombination and instability. Here, we develop stable CsPbBr₃/titania microspheres (TMs) by in situ growth of CsPbBr₃ NCs inside mesoporous TMs through solid-state sintering, which significantly improves the stability of perovskite NCs, making them applicable in water with efficient CO₂ photoreduction performance. Notably, the CsPbBr₃/TMs demonstrates a 6.73- and 9.23-fold increase in the rate of CH₄ production compared to TMs and CsPbBr₃, respectively. The internal electric field facilitates S-scheme charge transfer, enhancing the separation of electron–hole pairs, as evidenced by X-ray photoelectron spectroscopy and electron paramagnetic resonance analysis, which is pivotal for the selective photoreduction of CO₂. These insights pave the way for the design of CsPbBr₃-based photocatalysts with superior efficiency and stability.

中文翻译：

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原位封装在 TiO2 微球中的钙钛矿纳米晶体可在水中实现稳定的 CO2 光还原


将二氧化碳（CO ₂ ）光还原为燃料为缓解全球变暖和能源危机提供了一种有前景的方法。具有突出光电特性的卤化物钙钛矿纳米晶体（NC）作为光催化剂引起了广泛关注，但受到电荷复合和不稳定性的限制。在此，我们通过固态烧结在介孔TM内原位生长CsPbBr ₃ /二氧化钛微球（TM），显着提高了钙钛矿NC的稳定性，使其适用于水中，具有高效的 CO ₂ 光还原性能。值得注意的是，与 TM 和 CsPbBr ₃ 相比，CsPbBr ₃ /TM 的 CH ₄ 生成速率分别增加了 6.73 倍和 9.23 倍。 X射线光电子能谱和电子顺磁共振分析表明，内部电场促进S型电荷转移，增强电子-空穴对的分离，这对于CO的选择性光还原至关重要 ₂ 。这些见解为设计具有卓越效率和稳定性的 CsPbBr ₃ 基光催化剂铺平了道路。