Novel Au/La-Bi5O7I Microspheres with Efficient Visible-Light Photocatalytic Activity for NO Removal: Synergistic Effect of Au Nanoparticles, La Doping, and Oxygen Vacancy
Novel Au/La-Bi5O7I Microspheres with Efficient Visible-Light Photocatalytic Activity for NO Removal: Synergistic Effect of Au Nanoparticles, La Doping, and Oxygen Vacancy
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具有高效可见光光催化活性的新型 Au/La-Bi5O7I 微球去除 NO：Au 纳米颗粒、La 掺杂和氧空位的协同效应
DOI：
10.1021/acsami.9b14300
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发表时间：
2019
影响因子：
9.5
通讯作者：
Hojamberdiev Mirabbos
中科院分区：
文献类型：
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作者：
Zhang Jingyu;Zhu Gangqiang;Li Shiping;Rao Fei;Qadeer-Ul Hassan;Gao Jianzhi;Huang Yu;Hojamberdiev Mirabbos
采用溶剂热法制备了La掺杂的球形Bi 5 O 7 I（L-BOI）样品，并在450 °C下煅烧2 h。采用室温化学还原法将Au纳米粒子负载到6%La掺杂的Bi_5 O_7 I（2%A-6%L-BOI）微球上。紫外-可见吸收光谱表明，与纯BOI相比，L-BOI和2%A-6%L-BOI样品具有较强的可见光吸收。电子顺磁共振结果表明，在L-BOI样品中的氧空位的数量增加与La掺杂量的增加。分别通过XPS-VB测量的价带（VB）位置和密度泛函理论计算的费米能级来研究所制备的光催化剂的能带结构。选择NO作为目标气体污染物，以确认La掺杂和Au纳米粒子的等离子体效应对BOI微球的光催化活性的影响。与BOI、L-BOI和A-BOI光催化剂相比，2%A-6%L-BOI样品在可见光照射下表现出增强的光催化性能。有趣的是，2%A-6%L-BOI样品也可以减少NO去除过程中的中间体NO2的量。2%A-6% L-BOI光催化剂的光催化效率的提高得益于La离子掺杂、氧空位和Au纳米颗粒表面等离子体共振效应的协同作用。根据捕集实验和电子自旋共振谱测试结果，确定了NO的氧化去除过程中有H+、E-和·O2-参与。
Sphere-like Bi5O7I (BOI) doped with La (L-BOI) samples were prepared by a solvothermal method followed by calcination at 450 °C for 2 h. Au nanoparticles were loaded on 6% La-doped Bi5O7I (2%A–6%L-BOI) microspheres by a room-temperature chemical reduction method. The UV–vis absorption spectra show that the L-BOI and 2%A–6%L-BOI samples have a strong visible-light absorption in comparison with the pure BOI. The electron paramagnetic resonance results indicate that the number of oxygen vacancies in L-BOI samples is increased with an increasing amount of the La dopant. The band structure of the prepared photocatalysts is investigated by confirming the positions of the valence band (VB) measured by XPS-VB and the Fermi level computed by density functional theory, respectively. NO is selected as a target gaseous pollutant to confirm the influence of La doping and the plasmonic effect of Au nanoparticles on the photocatalytic activity of BOI microspheres. The 2%A–6%L-BOI sample exhibits an enhanced photocatalytic performance compared to BOI, L-BOI, and A-BOI photocatalysts under visible-light irradiation. Interestingly, the 2%A–6%L-BOI sample also can reduce the amount of intermediate NO2during the NO removal process. The enhanced photocatalytic efficiency of the 2%A–6%L-BOI photocatalyst is profited from the synergy of La-ion doping, oxygen vacancy, and the surface plasmon resonance effect of Au nanoparticles. Based on the results of trapping experiments and electron spin resonance spectroscopy tests, h+, e–, and•O2–were involved in the NO oxidative removal.