Metal halide perovskite nanocrystals (MHP NCs) have attracted much scientific interest in photocatalysis. Various types of MHP photocatalysts have been intensively explored in photocatalytic CO₂ reduction in the past few years. However, some key issues, such as severe charge recombination, low stability, and the origin of products, have created bottlenecks in developing MHP photocatalysts. Therefore, the rational design of MHPs is worthwhile to deepen our understanding of the above issues and develop efficient photocatalysts. This Focus Review highlights the recent advances in MHP photocatalysts regarding design principles toward photocatalytic CO₂ reduction. Various modification strategies are clarified, and an outlook on future challenges and prospects is also provided to point out the possible research directions in MHP photocatalysts. It is anticipated that this Focus Review can provide guidance on the design of MHP-based photocatalysts and help uncover some common issues encountered by the scientific community when studying MHP photocatalysts.

中文翻译：

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用于光催化 CO2 还原的金属卤化物钙钛矿纳米晶体的合理设计：最新进展、挑战和前景

金属卤化物钙钛矿纳米晶体（MHP NCs）在光催化领域引起了广泛的科学兴趣。近年来，各种类型的MHP光催化剂在光催化CO ₂还原方面得到了深入的探索。然而，一些关键问题，如严重的电荷复合、低稳定性和产物的来源，已经成为开发 MHP 光催化剂的瓶颈。因此，合理设计MHPs对于加深我们对上述问题的理解和开发高效的光催化剂是值得的。_{本焦点综述重点介绍了 MHP 光催化剂在光催化 CO 2}设计原则方面的最新进展减少。阐明了各种改性策略，并对未来的挑战和前景进行了展望，以指出MHP光催化剂可能的研究方向。预计本次焦点综述可为基于 MHP 的光催化剂的设计提供指导，并有助于揭示科学界在研究 MHP 光催化剂时遇到的一些常见问题。