采用光还原法将AgCl中的Ag+还原为Ag0,同时将其负载于钛酸盐BaTiO3的表面,制备了具有高催化性能的三元复合型光催化剂BaTiO3/Ag/AgCl。利用X射线衍射(XRD)、场发射扫描电子显微镜(FE-SEM)、X光电子能谱(XPS)、紫外-可见漫反射光谱和荧光光谱等手段对复合光催化剂的物相结构和形貌、元素价态、光学性能等进行了表征,通过在可见光下降解罗丹明B(Rh B)溶液,对复合光催化剂的性能进行了探究。结果表明:以AgNO3为银源,HCl为沉淀剂,得到AgCl并将其负载到BaTiO3表面,当n(AgNO3)∶n(BaTiO3)=20∶100,光还原时间为30min时,所得到的20% BaTiO3/Ag/AgCl复合光催化剂光催化性能最佳,在可见光照射75min后,对Rh B的降解率达到98.1%,捕获剂实验表明O-2为主要活性物种。
The photoreduction method was used to reduce Ag+ in AgCl to Ag0,and at the same time,it was successfully loaded on the surface of titanate BaTiO3 to prepare BaTiO3/Ag/AgCl ternary composite photocatalyst with high performance.Using X-ray diffraction (XRD),field emission scanning electron microscope (FE-SEM),X-ray electron spectroscopy (XPS),ultraviolet-visible diffuse reflectance spectroscopy and fluorescence spectroscopy,the phase structure,morphology,valence state of element and optical properties of the photocatalyst were characterized.The performance of the photocatalyst was explored by degrading rhodamine B (Rh B) solution under visible light.The results shown that AgNO3 was used as the silver source and HCl as the precipitant to obtain AgCl,and load it on the surface of BaTiO3.When n(AgNO3)∶n(BaTiO3)=20∶100 and the photoreduction time was 30min,the obtained 20% BaTiO3/Ag/AgCl had the best performance.After 75min of visible light irradiation,the degradation rate of Rh B reached 98.1%.The capture agent experiment shown that O-2 was the main active species.
[1] Herrmann J M.Heterogeneous photocatalysis:fundamentals and applications to the removal of various types of aqueous pollutants[J].Catalysis Today,1999,53(1):115-129.
[2] Linsebigler A L,Lu G,Yates Jr J T.Photocatalysis on TiO2 surfaces:principles,mechanisms,and selected results[J].Chemical Reviews,1995,95(3):735-758.
[3] Liu G,Zhao Y,Sun C,et al.Synergistic effects of B/N doping on the visible-light photocatalytic activity of mesoporous TiO2[J].Angewandte Chemie International Edition,2008,47(24):4516-4520.
[4] Devi L G,Krishnamurthy G.TiO2-and BaTiO3-assisted photocatalytic degradation of selected chloroorganic compounds in aqueous medium:correlation of reactivity/orientation effects of substituent groups of the pollutant molecule on the degradation rate[J].The Journal of Physical Chemistry A,2011,115(4):460-469.
[5] Xian T,Yang H,Di L J,et al.Enhanced photocatalytic activity of BaTiO3@g-C3N4 for the degradation of methyl orange under simulated sunlight irradiation[J].Journal of Alloys and Compounds,2015,622:1098-1104.
[6] Zou J P,Zhang L Z,Luo S L,et al.Preparation and photocatalytic activities of two new Zn-doped SrTiO3 and BaTiO3 photocatalysts for hydrogen production from water without cocatalysts loading[J].International Journal of Hydrogen Energy,2012,37(22):17068-17077.
[7] Cui Y,Briscoe J,Dunn S.Effect of ferroelectricity on solar-light-driven photocatalytic activity of BaTiO3-influence on the carrier ceparation and stern layer formation[J].Chemistry of Materials,2013,25(21):4215-4223.
[8] Fan H,Li H,Liu B,et al.Photoinduced charge transfer properties and photocatalytic activity in Bi2O3/BaTiO3 composite photocatalyst[J].ACS Applied Materials Interfaces,2012,4(9):4853-4857.
[9] Lin X,Xing J,Wang W,et al.Photocatalytic activities of heterojunction semiconductors Bi2O3/BaTiO3:a strategy for the design of efficient combined photocatalysts[J].The Journal of Physical Chemistry C,2007,111(49):18288-18293.
[10] Kanhere P,Chen Z.A review on visible light active perovskite-based photocatalysts[J].Molecules,2014,19(12):19995-20022.
[11] Kappadan S,Gebreab T W,Thomas S,et al.Tetragonal BaTiO3 nanoparticles:an efficient photocatalyst for the degradation of organic pollutants[J].Materials Science in Semiconductor Processing,2016,51:42-47.
[12] Hu C,Peng T,Hu X,et al.Plasmon-induced photodegradation of toxic pollutants with Ag-AgI/Al2O3 under visible-light irradiation[J].Journal of the American Chemical Society,2010,132(2):857-862.
[13] Zhang L S,Wong K H,Yip H Y,et al.Effective photocatalytic disinfection of E.coli K-12 using AgBr-Ag-Bi2WO6 nanojunction system irradiated by visible light:the role of diffusing hydroxyl radicals[J].Environmental Science & Technology,2010,44(4):1392-1398.
[14] Yang Y,Guo W,Guo Y,et al.Fabrication of Z-scheme plasmonic photocatalyst Ag@ AgBr/g-C3N4 with enhanced visible-light photocatalytic activity[J].Journal of Hazardous Materials,2014,271:150-159.
[15] Wang X,Yang S,Tian L.Synthesis and photocatalytic activity of Ag@AgCl modified ZnO[J].Asian Journal of Chemistry,2014,26(6):1735-1737.
[16] Wang L,Niu C G,Wang Y,et al.The synthesis of Ag/AgCl/BiFeO3 photocatalyst with enhanced visible photocatalytic activity[J].Ceramics International,2016,42(16):18605-18611.
[17] 樊苗苗,樊国栋,郑少芳,等.AgBr-Ag3PO4-CSs三元复合光催化剂的制备及性能[J].硅酸盐学报,2019,47(4):36-43.
[18] Xu S,Liu Z,Zhang M,et al.Piezotronics enhanced photocatalytic activities of Ag-BaTiO3 plasmonic photocatalysts[J].Journal of Alloys and Compounds,2019,801:483-488.
[19] Alex K V,Prabhakaran A,Jayakrishnan A R,et al.Charge coupling enhanced photocatalytic activity of BaTiO3/MoO3 heterostructures[J].ACS Applied Materials & Interfaces,2019,11(43):40114-40124.
[20] Ye L,Liu J,Gong C,et al.Two different roles of metallic Ag on Ag/AgX/BiOX (X=Cl,Br) visible light photocatalysts:surface plasmon resonance and Z-scheme bridge[J].ACS Catalysis,2012,2(8):1677-1683.
[21] Zhang S,Li J,Wang X,et al.In situ ion exchange synthesis of strongly coupled Ag@ AgCl/g-C3N4 porous nanosheets as plasmonic photocatalyst for highly efficient visible-light photocatalysis[J].ACS Applied Materials & Interfaces,2014,6(24):22116-22125.
