In this paper, a composite photocatalyst is prepared by using waste clay bricks to adsorb nano-TiO2, and the decorative concrete surface layer is made by using it. Then, it is found that the reclaimed clay sand (RCA) prepared by building waste clay bricks has poor workability, with the relative strength between 40% and 80%, but can meet the strength requirements of ordinary building mortar. Compared with RCA, the natural sand (NS) has lower water absorption, coarser particles and higher hardness. The relative strength of the mortar prepared by it is between 50% and 80%, which also meets the basic strength requirements of the mortar. In terms of photocatalytic effect, the decorative concrete surface layer prepared by the composite photocatalyst has good photocatalytic effect and can effectively degrade NOx in automobile exhaust. The decorative concrete surface layer made of NS has lower degradation efficiency of NOx than RCA. Photocatalytic concrete surface layer prepared by RCA loaded with nano-TiO2 has good photocatalytic durability.

中文翻译：

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废粘土砖制备纳米TiO2及其对混凝土的光催化作用

本文利用废粘土砖吸附纳米TiO2制备复合光催化剂，并用其制备装饰性混凝土表层。然后，发现用建筑废粘土砖制备的再生粘土砂（RCA）的可加工性较差，相对强度在40％至80％之间，但可以满足普通建筑砂浆的强度要求。与RCA相比，天然砂（NS）具有较低的吸水率，较粗的颗粒和较高的硬度。由其制备的砂浆的相对强度在50％至80％之间，也满足了砂浆的基本强度要求。就光催化作用而言，由复合光催化剂制备的装饰性混凝土表面层具有良好的光催化作用，并能有效降解汽车尾气中的NOx。由NS制成的混凝土装饰表面层的NOx降解效率低于RCA。RCA负载纳米TiO2制备的光催化混凝土表面层具有良好的光催化耐久性。