Luan Jingfei, Liu Wenlu, Yao Ye, Ma Bingbing, Niu Bowen, Yang Guangmin, Wei Zhijie
School of Physics, Changchun Normal University, Changchun 130032, China.
State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093, China.
Materials (Basel). 2022 Aug 26;15(17):5906. doi: 10.3390/ma15175906.
A new photocatalyst, Er2FeSbO7, was prepared by solid phase sintering using the high-temperature synthesis method for the first time in this paper. Er2FeSbO7/BiTiSbO6 heterojunction (EBH) catalyst was prepared by the solvent thermal method for the first time. Er2FeSbO7 compound crystallized in the pyrochlore-type architecture and cubelike crystal system; the interspace group of Er2FeSbO7 was Fd3m and the crystal cellular parameter a of Er2FeSbO7 was 10.179902 Å. The band gap (BDG) width of Er2FeSbO7 was 1.88 eV. After visible light irradiation of 150 minutes (VLGI-150min) with EBH as a photocatalyst, the removal rate (RR) of enrofloxacin (ENR) concentration was 99.16%, and the total organic carbon (TOC) concentration RR was 94.96%. The power mechanics invariable k toward ENR consistency and visible light irradiation (VLGI) time with EBH as a photocatalyzer attained 0.02296 min−1. The power mechanics invariable k which was involved with TOC attained 0.01535 min−1. The experimental results showed that the photocatalytic degradation (PCD) of ENR within pharmaceutical waste water with EBH as a photocatalyzer under VLGI was in keeping with the single-order reactivity power mechanics. The RR of ENR with EBH as a photocatalyzer was 1.151 times, 1.269 times or 2.524 times that with Er2FeSbO7 as a photocatalyst, BiTiSbO6 as a photocatalyst, or N-doping TiO2 (N-TO) as a photocatalyst after VLGI-150min. The photocatalytic activity, which ranged from high to low among above four photocatalysts, was as follows: EBHP > Er2FeSbO7 > BiTiSbO6 > N-TO. After VLGI-150min toward three periods of the project with EBH as a photocatalyst, the RR of ENR attained 98.00%, 96.76% and 95.60%. The results showed that the stability of EBH was very high. With appending trapping agent, it could be proved that the oxidative capability for degrading ENR, which ranged from strong to weak among three oxidic radicals, was as follows: superoxide anion > hydroxyl radicals (HRS) > holes. This work provides a scientific basis for the research and oriented leader development of efficient heterojunction catalysts.
本文首次采用高温合成法通过固相烧结制备了一种新型光催化剂Er2FeSbO7。首次采用溶剂热法制备了Er2FeSbO7/BiTiSbO6异质结（EBH）催化剂。Er2FeSbO7化合物以烧绿石型结构和立方晶系结晶；Er2FeSbO7的空间群为Fd3m，晶体胞参数a为10.179902 Å。Er2FeSbO7的带隙（BDG）宽度为1.88 eV。以EBH为光催化剂进行150分钟可见光照射（VLGI - 150min）后，恩诺沙星（ENR）浓度的去除率（RR）为99.16%，总有机碳（TOC）浓度RR为94.96%。以EBH为光催化剂时，对ENR一致性和可见光照射（VLGI）时间的动力学常数k达到0.02296 min−1。与TOC相关的动力学常数k达到0.01535 min−1。实验结果表明，在VLGI条件下，以EBH为光催化剂对制药废水中ENR的光催化降解（PCD）符合一级反应动力学。以EBH为光催化剂时，VLGI - 150min后ENR的RR分别是以Er2FeSbO7为光催化剂、以BiTiSbO6为光催化剂或以N掺杂TiO2（N - TO）为光催化剂时的1.151倍、1.269倍或2.524倍。上述四种光催化剂的光催化活性从高到低依次为：EBHP > Er2FeSbO7 > BiTiSbO6 > N - TO。以EBH为光催化剂对该项目的三个阶段进行VLGI - 150min后，ENR的RR分别达到98.00%、96.76%和95.60%。结果表明EBH的稳定性非常高。通过添加捕获剂可以证明，在三种氧化自由基中，降解ENR的氧化能力从强到弱依次为：超氧阴离子 > 羟基自由基（HRS） > 空穴。这项工作为高效异质结催化剂的研究和定向引领发展提供了科学依据。
