In this study, an effort has been made to synthesize diatomite/silver phosphate (DT/AgP) composites and dye degradation test was carried out to evaluate the photocatalytic activity under solar light irradiation. Diatomite–silver phosphate composites with different DT/AgP ratios were prepared by precipitation of Ag 3 PO 4 on diatomite that led to the formation of small Ag 3 PO 4 particles on the diatomite surfaces. UV–visible diffuse reflectance analysis shows that DT/AgP composites can absorb visible wavelength, whereas TiO 2 catalyst only work under UV irradiance. Compared to pure AgP, the composite samples show higher specific surface area measured by Brunauer–Emmett–Teller analysis. Dye degradation test under solar light irradiation reveals that the photocatalytic reaction follows a pseudo-first-order rate law and the composite catalyst with DT/AgP ratio 1:0.8 shows better catalytic activity towards both rhodamine B and methyl orange degradation. As reference, a well-known commercial TiO 2 (Evonik-P25) was used in dye degradation test. It could be presumed that deposition of silver phosphate clusters (Ag 3 PO 4 , AgP) on diatom frustules (diatomite) provided an efficient photocatalyst activated by solar light irradiation.

中文翻译：

---

硅藻土/磷酸银复合材料在太阳辐射下有效降解有机染料

在这项研究中，已经努力合成硅藻土/磷酸银（DT/AgP）复合材料，并进行了染料降解试验以评估在太阳光照射下的光催化活性。通过在硅藻土上沉淀 Ag 3 PO 4 导致在硅藻土表面形成小的 Ag 3 PO 4 颗粒，制备了具有不同 DT/AgP 比的硅藻土-磷酸银复合材料。紫外可见漫反射分析表明，DT/AgP 复合材料可以吸收可见光波长，而 TiO 2 催化剂只能在紫外光照射下工作。与纯 AgP 相比，通过 Brunauer-Emmett-Teller 分析测量的复合样品显示出更高的比表面积。太阳光照射下的染料降解试验表明，光催化反应遵循拟一级速率规律，DT/AgP比为1:0.8的复合催化剂对罗丹明B和甲基橙的降解具有更好的催化活性。作为参考，在染料降解测试中使用了众所周知的商业TiO 2 (Evonik-P25)。可以推测，磷酸银簇（Ag 3 PO 4 ，AgP）在硅藻壳（硅藻土）上的沉积提供了一种由太阳光照射激活的有效光催化剂。