School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, China.
Faculty of Environmental & Biological Engineering, Guangdong University of Petrochemical Technology, Maoming, 525000, China.
J Hazard Mater. 2020 Jun 15;392:122355. doi: 10.1016/j.jhazmat.2020.122355. Epub 2020 Feb 19.
As a metal-free photocatalyst, the photocatalytic activity of graphitic carbon nitride (g-CN) remains restricted due to an insufficient visible-light absorption capacity, the rapid recombination of photoinduced carriers, and low surface area. Consequently, P-doped g-CN (PCN) was successfully prepared via a single -step thermal polymerization technique using phytic acid biomass and urea, which exhibited remarkable photocatalytic activity for the degradation of indometacin (IDM). The IDM degradation rate was 7.1 times greater than that of pristine g-CN (CN). Furthermore, AgWO was loaded onto the surface of the PCN, which formed a Z-scheme heterostructure that promoted the separation of photogenerated carriers. According to analyses of the chemical binding states of PCN, P atoms replaced carbon atoms in the CN framework. According to electron localization function analysis, the low ELF values of P-N facilitated the transfer of photoelectrons. The results of active species scavenging experiments confirmed that superoxide radicals were the primary active species in the photocatalytic degradation system. Finally, the photocatalytic degradation pathways of IDM were predicted through the identification of by-products and IDM reaction sites.
作为一种无金属光催化剂，石墨相氮化碳（g-CN）的光催化活性由于可见光吸收能力不足、光生载流子的快速复合以及表面积低而受到限制。因此，通过使用植酸生物质和尿素的一步热聚合技术成功制备了 P 掺杂 g-CN（PCN），其在降解吲哚美辛（IDM）方面表现出显著的光催化活性。IDM 的降解速率比原始 g-CN（CN）高 7.1 倍。此外，AgWO 负载在 PCN 的表面上，形成 Z 型异质结构，促进光生载流子的分离。通过对 PCN 的化学结合状态分析，发现 P 原子取代了 CN 框架中的碳原子。根据电子定域函数分析，P-N 的低 ELF 值有利于光电子的转移。通过捕获实验确认了超氧自由基是光催化降解体系中的主要活性物质。最后，通过鉴定副产物和 IDM 反应位点预测了 IDM 的光催化降解途径。
