共沉淀法制备Ag3PO4/MWCNTs复合光催化材料及其表征与降解染料废水

通过简单的共沉淀法制备掺杂不同碳管含量的Ag₃PO₄/MWCNTs复合光催化材料，并对样品进行XRD、SEM、FT-IR、UV-vis等表征。以300 W氙灯模拟太阳光，通过光催化材料对甲基橙的降解来评价光催化材料对印染废水的催化效果。结果表明：PVP的存在使得制备的Ag₃PO₄颗粒表面光滑、结晶性好、尺寸较小（200~300 nm）；经过混酸改性后增加了大量的带有羧基基团的碳管，均匀地分布在Ag₃PO₄颗粒表面，与其形成了很好的复合；合成的复合材料较纯Ag₃PO₄具有更加优异的光催化活性，当碳管质量分数为3.6%时催化效果最好。最后，对所制备材料的光催化机理进行了分析。

Preparation of Ag3PO4/MWCNT composites by a chemical coprecipitation process and their use in the degradation of dye wastewater

Novel Ag₃PO₄/MWCNTs composite photocatalysts with different CNTs contents have been successfully synthesized by a simple precipitation process and characterized by XRD, SEM, UV-vis and FT-IR. The photocatalytic performance of the as-prepared photocatalysts in the degradation of dye wastewater was tested using methyl orange (MO) as a representative dye under simulated visible light irradiation by a 300 WXe lamp. The results showed that Ag₃PO₄ nanoparticles exhibit high crystallinity and smaller size (200-300 nm) when prepared in the presence of PVP. A mixed acid treatment results in the formation of a large number carboxyl groups on the surface of MWCNTs, which promotes the coupling with Ag₃PO₄ nanoparticles. Ag₃PO₄/3.6% MWCNTs displayed a higher photocatalytic activity than pure Ag₃PO₄ and other composites contained different CNTs contents. The mechanism for the photocatalytic degradation of MO is discussed at the end of this paper.