Developing suitable photocatalysts and understanding their intrinsic catalytic mechanism remain key challenges in the pursuit of highly active, good selective, and long-term stable photocatalytic CO reduction (PCOR) systems. Herein, monoclinic Cu(OH)CO is firstly proven to be a new class of photocatalyst, which has excellent catalytic stability and selectivity for PCOR in the absence of any sacrificial agent and cocatalysts. Based on a Cu(OH)CO photocatalyst and CO two-sided C isotopic tracer strategy, and combined with in situ diffused reflectance infrared Fourier transform spectroscopy (DRIFTS) analysis and density functional theory (DFT) calculations, two main CO transformation routes, and the photo-decomposition and self-restructuring dynamic equilibrium mechanism of Cu(OH)CO are definitely revealed. The PCOR activity of Cu(OH)CO is comparable to some of state-of-the-art novel photocatalysts. Significantly, the PCOR properties can be further greatly enhanced by simply combining Cu(OH)CO with typical TiO to construct composites photocatalyst. The highest CO and CH production rates by 7.5 wt% Cu(OH)CO-TiO reach 16.4 μmol gh and 116.0 μmol gh, respectively, which are even higher than that of some of PCOR systems containing sacrificial agents or precious metals modified photocatalysts. This work provides a better understanding for the PCOR mechanism at the atomic levels, and also indicates that basic carbonate photocatalysts have broad application potential in the future.

中文翻译：

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Cu2(OH)2CO3稳定光催化CO2还原的光分解和自重构动态平衡机制

开发合适的光催化剂并了解其内在催化机制仍然是追求高活性、良好选择性和长期稳定的光催化二氧化碳还原（PCOR）系统的关键挑战。在此，单斜晶系Cu(OH)CO首次被证明是一类新型光催化剂，在没有任何牺牲剂和助催化剂的情况下，对PCOR具有优异的催化稳定性和选择性。基于Cu(OH)CO光催化剂和CO双面C同位素示踪策略，并结合原位漫反射红外傅里叶变换光谱(DRIFTS)分析和密度泛函理论(DFT)计算，两种主要的CO转化路线，以及明确揭示了Cu(OH)CO的光分解和自重构动态平衡机制。 Cu(OH)CO 的 PCOR 活性可与一些最先进的新型光催化剂相媲美。值得注意的是，通过简单地将 Cu(OH)CO 与典型的 TiO 结合构建复合光催化剂，可以进一步大大增强 PCOR 性能。 7.5 wt% Cu(OH)CO-TiO 的最高 CO 和 CH 产率分别达到 16.4 μmol gh 和 116.0 μmol gh，甚至高于一些含有牺牲剂或贵金属改性光催化剂的 PCOR 系统。这项工作为原子水平上的PCOR机理提供了更好的理解，也表明碱性碳酸盐光催化剂在未来具有广阔的应用潜力。