This study aims to understand the impact of carbonation on the photocatalytic self-cleaning and radiative cooling properties of autoclaved cement composites. The composites are prepared with varying silica contents and sources, with and without alumina addition under autoclave conditions. The phase composition, microstructure, optical properties, and photocatalytic self-cleaning performance are systematically characterized and analyzed. Outdoor measurements are conducted to validate the cooling performance of the material under ambient conditions. Cracking behaviors during autoclave/carbonation treatments and the performance degradation in functionalities upon carbonation are observed. The cement/nanosilica/alumina ternary system demonstrates the best overall performance, considering productibility during autoclave curing, effectiveness, and carbonation durability of functionalities. C-A-S-H minerals, mainly Al-Foshagite, in this system, serve as precursors for the generation of γ-AlO upon carbonation, mitigating the deterioration of photocatalytic properties. The findings are expected to provide new insights for the development and engineering practice of functional cementitious materials for durable cooling applications.

中文翻译：

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光催化铝硅酸盐水泥复合材料的碳化：自清洁和辐射冷却性能的演变


本研究旨在了解碳化对蒸压水泥复合材料光催化自清洁和辐射冷却性能的影响。该复合材料采用不同的二氧化硅含量和来源，在高压釜条件下添加或不添加氧化铝来制备。对相组成、微观结构、光学性能和光催化自清洁性能进行了系统的表征和分析。进行室外测量是为了验证材料在环境条件下的冷却性能。观察到高压釜/碳酸化处理期间的开裂行为以及碳酸化时功能的性能下降。考虑到高压釜固化过程中的生产率、有效性和功能的碳化耐久性，水泥/纳米二氧化硅/氧化铝三元系统表现出最佳的整体性能。该系统中的 C-A-S-H 矿物（主要是 Al-Foshagite）可作为碳酸化时生成 γ-Al2O 的前体，从而减轻光催化性能的恶化。研究结果预计将为用于耐用冷却应用的功能性水泥材料的开发和工程实践提供新的见解。