Synthesis of ZnO@γ-Fe2O3 core–shell nanocomposites by a facile thermal decomposition approach and their application in photocatalytic degradation of congo red
ZnO@γ-Fe2O3 core–shell nanocomposites were synthesized by a facile thermal decomposition approach. ZnO nanorods were first synthesized by calcination of zinc acetate at 300 °C, in air. γ-Fe2O3 nanoparticles were then deposited on the surface of ZnO nanorods by the thermal decomposition of iron acetylacetonate at 200 °C in diphenyl ether. The structure, composition, optical and magnetic properties of the nanocomposites were studied using an array of techniques. XRD results suggest the presence of γ-Fe2O3 nanoparticles and ZnO, and FE-SEM images indicate formation of shell of iron oxide on the ZnO nanorods. Transmission electron microscopy studies clearly show that ZnO possesses rod morphology (length = 1.1 ± 0.1 μm, diameter = 40.1 ± 7 nm) and TEM images of the ZnO@γ-Fe2O3 nanocomposites show uniform shell of γ-Fe2O3 coated on the ZnO nanorods and thickness of the γ-Fe2O3 shell varies from 10 to 20 nm. Diffuse reflectance spectra of ZnO@γ-Fe2O3 nanocomposites reveal extended optical absorption in the visible range (400–600 nm) and photoluminescence spectra indicate that the ZnO@γ-Fe2O3 nanocomposites exhibit enhanced defect emission. The ZnO@γ-Fe2O3 core–shell nanocomposites show superparamagnetic behaviour at room temperature. The core–shell nanocomposites exhibit enhanced visible-light driven photocatalytic degradation of congo red in an aqueous solution as compared to pure ZnO nanorods and γ-Fe2O3 nanoparticles. The enhanced photocatalytic activity is attributed to good visible-light absorption and effective charge separation at the interface of ZnO@γ-Fe2O3 core–shell nanocomposites.
KeywordsZnO@γ-Fe2O3 core–shell nanocomposites Thermal decomposition Photocatalytic degradation
P. J thanks the Council of Scientific and Industrial Research (CSIR), New Delhi for the financial support (Project No. 01(2726)/13/EMR-II). The award of Research Fellowship to Mr. Sudheer Kumar Yadav by the University Grants Commission, Government of India, is gratefully acknowledged. The authors are also thankful to the Institute Instrumentation Centre, Indian Institute of Technology Roorkee for providing the facilities.
- Chen YJ, Zhang F, Zhao GG, Fang XY, Jin HB, Gao P, Zhu CL, Cao MS, Xiao G (2010b) Synthesis, multi-nonlinear dielectric resonance, and excellent electromagnetic absorption characteristics of Fe3O4/ZnO core/shell nanorods. J Phys Chem C 114(20):9239–9244. doi: 10.1021/jp912178q CrossRefGoogle Scholar
- Guo N, Liang Y, Lan S, Liu L, Zhang J, Ji G, Gan S (2014) Microscale hierarchical three-dimensional flowerlike TiO2/PANI composite: synthesis, characterization, and its remarkable photocatalytic activity on organic dyes under UV-light and sunlight irradiation. J Phys Chem C 118(32):18343–18355. doi: 10.1021/jp5044927 CrossRefGoogle Scholar
- Jiang R, Yao J, Zhu H, Fu Y, Guan Y, Xiao L, Zeng G (2014) Effective decolorization of congo red in aqueous solution by adsorption and photocatalysis using novel magnetic alginate/γ-Fe2O3/CdS nanocomposite. Desalin Water Treat 52(1–3):238–247. doi: 10.1080/19443994.2013.787551 CrossRefGoogle Scholar
- Maya-Treviño ML, Guzmán-Mar JL, Hinojosa-Reyes L, Ramos-Delgado NA, Maldonado MI, Hernández-Ramírez A (2014) Activity of the ZnO-Fe2O3 catalyst on the degradation of Dicamba and 2,4-D herbicides using simulated solar light. Ceram Int 40(6):8701–8708. doi: 10.1016/j.ceramint.2014.01.088 CrossRefGoogle Scholar
- Saffari J, Mir N, Ghanbari D, Khandan-Barani K, Hassanabadi A, Hosseini-Tabatabaei MR (2015) Sonochemical synthesis of Fe3O4/ZnO magnetic nanocomposites and their application in photo-catalytic degradation of various organic dyes. J Mater Sci Mater Electron 26(12):9591–9599. doi: 10.1007/s10854-015-3622-y CrossRefGoogle Scholar
- Wang J, Li R, Zhang Z, Sun W, Xu R, Xie Y, Xing Z, Zhang X (2008) Efficient photocatalytic degradation of organic dyes over titanium dioxide coating upconversion luminescence agent under visible and sunlight irradiation. Appl Catal A Gen 334(1–2):227–233. doi: 10.1016/j.apcata.2007.10.009 CrossRefGoogle Scholar