银纳米粒子沉积含有氧空位的钒酸铋能够提高其近红外光催化性能（英文）

钒酸铋因其独有的廉价、低毒性、热稳定性和高氧化性能等特性而备受瞩目,是利用太阳能降解污染物、水分解等应用方面最优选择的半导体纳米材料之一.选择表面粗糙多孔尺寸均匀的橄榄状钒酸铋有助于吸附更多的电子受体参与到半导体表面的氧化还原反应当中,从而提高其光催化活性.另外,太阳能谱中紫外光占不到5%,可见光占45%,与传统的半导体TiO_2材料相比,钒酸铋禁带宽度在2.4 eV左右,能较好地吸收太阳光能实现光能转化.但是太阳光中近一半的光能属于近红外,不能被传统的纯相钒酸铋所利用.为了更好地利用太阳能,可将氧空位缺陷引入到钒酸铋晶体中,以实现近红外光能的转化利用.氧空位缺陷在半导体材料中不仅能够吸收近红外光,在低于导带的位置形成电子传输的桥梁,而且能够吸附更多的氧分子转化成活性物种.另一方面,氧空位缺陷态的引入使半导体钒酸铋材料暴露更多的活性位点,参与到溶液的氧化还原反应中.由于钒酸铋光激发的载流子浓度有限,并且光生电子-空穴容易复合,本文采用银纳米粒子负载在钒酸铋表面,利用其等离子共振效应产生的热电子与氧空位缺陷的协同作用,能够提高其载流子传输速率,抑制光生电子-空穴复合,达到更优的光能到化学能转化的目的.基于此,本文采用电子自旋共振光谱(ESR),X射线光电子能谱(XPS)和紫外可见光谱(UV-Vis)等手段研究了氧空位缺陷引入到钒酸铋以及Ag纳米粒子担载于橄榄状半导体材料上对光催化降解罗丹明B染料中太阳能驱动活性的影响.ESR结果证明,在测试过程中橄榄状钒酸铋材料吸收了更多的电子,表明存在很多氧空位缺陷.XPS结果表明出现高浓度的吸收氧峰意味着钒酸铋材料上存在大量氧空位缺陷;银纳米粒子成功负载在具有氧空位缺陷的钒酸铋材料上.UV-Vis结果表明该材料光吸收范围扩展到近红外光范围,其禁带宽度比传统纯相钒酸铋减小,Ag-BiVO_4-OV样品的导价带位置发生明显变化.因此,由于氧空位和银纳米粒子存在于橄榄状钒酸铋主体中,其光催化降解罗丹明B的效率远远高于纯相钒酸铋样品.由此可见氧空位缺陷和银纳米粒子的引入使得半导体光催化材料光学性能正效应增加.Supporting Information for Ag nanoparticles deposited on oxygen-vacancy-containing BiV O4 for enhanced near-infrared photocatalytic activity Chunjing Shi,Xiaoli Dong*,Xiuying Wang,Hongchao Ma,Xiufang Zhang School of Light Industry and Chemical Engineering,Dalian Polytechnic University,Dalian 116034,Liaoning,China*Corresponding author.E-mail:dongxl@dlpu.edu.cn On the other hand,the nitrogen sorption isotherm of the reactions,but also can provide more surface active sites for as-prepared samples possesses an obvious condensation step oxygen activation and reduction,and thereby positively around P/P0=0.5-0.9,which is typical hysteresis loops of facilitating the reaction process and endowing the catalyst with mesoporous materials(Fig.S1).It is indicated that the robust redox kinetics.as-prepared Ag-BiV O4-OV possesses the mesoporous structure To further prove remarkable photocatalytic activities of the(Fig.S2).In addition,the Ag-BiV O4-OV exhibits ultra-large as-prepared samples,the photocatalytic activities of the typical surface area(34.8 m3/g),which is more than 2 times larger samples based on previous report was listed(Table S1).This than that of pure BiV O4(Fig.S1).The novel mesoporous statistics indicated that the as-prepared Ag-BiV O4-OV reveals structure and larger surface area not only can promote the more excellent photocatalytic performance.diffusion of active species and accelerate subsequent surface50Ag-Bi VO-OV41)-g3m40(c d Bi VO4be30ords a20me u olV1000.0 0.2 0.4 0.6 0.8 1.0Relative pressure(P/P)0Fig.S1.N2-sorption isotherm of pure BiV O4 and Ag-BiV O4-OV.Ag-Bi VO4-OV Bi VO41)-mn1-g3m(c D d V/d0 10 20 30 40 50 60 70 80Pore size(nm)Fig.S2.Pore size distributions of pure BiV O4 and Ag-BiV O4-OV.Table S1Summary for the photocatalytic activities of the typical samples.Sample Amount Amount of dye Light source Time Degradation rate Reference Ag-BiV O4-OV 20 mg 50 mL RhB(10 mg/L)simulated sunlight 100 min 99%this work mono-dispersed m-BiV O4 0.1 g 50 mL RhB(15μmol/L)visible light 10 h 99%1]BiV O4–Ag/Co3O4 100 mg 50 mL RhB(10 mg/L)simulated sunlight 120 min 97%2]the BiV O-4 80 mg 80 mL RhB(1×105 mol/L)visible light 6 h 97%3]Dy-BiV O4 50 mg 50 mL(10 mg/L)visible light 10 h 66.9%4]m-BiV O4 0.2 g 100 mL of RhB(0.01 mmol/L)visible light 150 min 98%5]BiV O4/CeO 2 50 mg 50 mL RhB(2×10-5 mol/L)visible light 210 min 90%6]

Ag nanoparticles deposited on oxygen-vacancy-containing BiVO4for enhanced near-infrared photocatalytic activity

This study investigates the photodegradation of the organic dye rhodamine B by Ag-nanoparticle-containing BiVO4catalysts under different irradiation conditions. The catalysts consist of Ag nano-particles deposited on oxygen-vacancy-containing BiVO4. The morphology of the BiVO4is olive shaped, and it has a uniform size distribution. The BiVO4possesses a high oxygen vacancy density, and the resulting Ag nanoparticle-BiVO4catalyst exhibits higher photocatalytic activity than BiVO4. The RhB degradation by the Ag nanoparticle-BiVO4catalyst is 99% after 100 min of simulated solar irradiation. BiVO4containing oxygen vacancies as a rationally designed support extends the catalyst response into the near-infrared region, and facilitates the trapping and transfer of plasmonic hot electrons. The enhanced photocatalytic efficiency is attributed to charge transfer from the BiVO4to Ag nanoparticles, and surface plasmon resonance of the Ag nanoparticles. These insights into elec-tron-hole separation and charge transfer may arouse interest in solar-driven wastewater treatment and water splitting.