1 Faculty of Science, Kunming University of Science and Technology, Kunming 650093 2 Yunnan Provincial Key Laboratory of Intensification Metallurgy, Kunming University of Science and Technology, Kunming 650093 3 Key Laboratory of Unconventional Metallurgy of Ministry of Education, Kunming 650093 4 National Local Joint Laboratory of Engineering Application of Microwave Energy and Equipment Technology, Kunming 650093 5 Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093
Abstract: The CdS/rGO nanocomposites were prepared via microwave-hydrothermal process. The structure and morphology of CdS/rGO composites was characterized by XRD, FTIR, XPS, SEM, and TEM. The mechanism of charge transfer for CdS/rGO heterogeneous interface was investigated by UV-Vis spectra combined density functional theory (DFT) calculations. The results indicated that the CdS in CdS/rGO displayed good dispersion, high photocatalytic activity, and excellent light stability. When the content of rGO was 0.5 mg/mL, the composite exhibited the best photocatalytic activity. The photodegradation rate of methylene blue (MB) reached 94.40 % after 120 min in visible light and the composite had the similar photocatalytic performance during five cycles. The DFT calculations such as interfacial interaction, charge density difference, ave-rage electrostatic potential et al revealed that the hetero-interface between CdS and rGO formed via van der Waals' interaction, which resulted in stabilization of composites. The introduction of rGO promoted the efficient transport of photo-induced electrons from CdS to the rGO, and gave rise to spatial separation of photo-generated electrons and holes. Hence, the enhancement of photocatalytic performance was observed.
1 Chen J, Wu X J, Yin L, et al.Angewandte Chemie, 2015, 54(4), 1210. 2 And D J, Guo L.Journal of Physical Chemistry B, 2006, 110(23),11139. 3 Cao W, Zhang X, Zheng Y, et al.International Journal of Hydrogen Energy, 2017, 42(5),2924. 4 Kansal S K, Singh M, Sud D.Journal of Hazardous Materials, 2007, 141(3),581. 5 Li Q, Guo B, Yu J, et al.Journal of the American Chemical Society, 2011, 133(28),10878. 6 Sun W T, Yu Y, Pan H Y, et al.Journal of the American Chemical Society, 2008, 130(4),1124. 7 Wang M, Cai L, Wang Y, et al. Journal of the American Chemical Society, 2017,139 (11), 4144. 8 Gao P, Liu J, Sun D D, et al.Journal of Hazardous Materials, 2013, s 250,412. 9 Min Y, He G, Xu Q, et al.Journal of Materials Chemistry A, 2014, 2(8),2578. 10 Cao S, Low J, Yu J, et al.Advanced Materials, 2015, 27(13),2150. 11 Zhang C, Chen G, Li C, et al.ACS Sustainable Chemistry & Engineering, 2016, 4(11),5936. 12 Geim A K.Science, 2009, 324(5934),1530. 13 Peng T, Li K, Zeng P, et al.Journal of Physical Chemistry C, 2015, 116(43),22720. 14 Xiao F X, Miao J, Liu B.Journal of the American Chemical Society, 2014, 136(4),1559. 15 Lin Y C, Tsai D C, Chang Z C, et al. Applied Surface Science,2018, 440, 1227. 16 Zhang N, Zhang Y, Pan X, et al. Journal of Physical Chemistry C, 2012, 116(6),18023. 17 Kaveri S, Thirugnanam L, Dutta M, et al.Ceramics International, 2013, 39(8),9207. 18 Liu J, Pu X, Zhang D, et al.Materials Research Bulletin, 2014, 57(23),29. 19 Ye A, Fan W, Zhang Q, et al.Catalysis Science & Technology, 2012, 2(5), 969. 20 Lee J S, You K H, Park C B, et al.Advanced Materials, 2012, 24(8), 1084. 21 Lv X, Fu W, Chang H, et al.Journal of Materials Chemistry, 2012, 22(4),1539. 22 Zhou K, Zhang J F, et al. Journal of Functional Materials, 2018, 49(5), 5016 (in Chinese). 周凯, 张建锋, 等.功能材料, 2018, 49(5), 5016. 23 Dong C, Li X, Jin P, et al.Journal of Physical Chemistry C, 2012, 116(29),15833. 24 Liu X, Pan L, Lv T, et al.Chemical Communications, 2011, 47(43),11984. 25 Yin R, Li J, Liu R, et al.Materials Review, 2011, 25(s1), 64(in Chinese). 殷蓉, 李景印, 刘瑞红,等.材料导报, 2011, 25(s1), 64. 26 Delley B.Journal of Chemical Physics, 2000, 113(18),7756. 27 Clark S J, Segall M D, Pickard C J, et al.Zeitschrift für Kristallographie, 2005, 220,567. 28 Perdew J P, Burke K, Ernzerhof M.Physical Review Letters, 1996, 77(18),3865. 29 Vanderbilt D.Physical Review B Condensed Matter, 1990, 41(11),7892. 30 Grimme S.Journal of Computational Chemistry, 2006, 27(15),1787. 31 Grimme S.Journal of Computational Chemistry, 2004, 25(12),1463. 32 Zhang H, Lv X, Li Y, et al.ACS Nano, 2010, 4(1),380. 33 Yang M Q, Weng B, Xu Y J.Langmuir the ACS Journal of Surfaces & Colloids, 2013, 29(33),10549. 34 Zhang C, Xu Y J.ACS Applied Materials & Interfaces, 2013, 5(24),13353 35 Yang G, Yan W, Zhang Q, et al.Nanoscale, 2013, 5(24),12432. 36 Ma D, Li X, Guo Y, et al.Acta Photonica Sinica, 2017, 46(12), 128(in Chinese). 马德跃, 李晓霞, 郭宇翔,等.光子学报, 2017, 46(12),128 37 Meissner D, Memming R, Kastening B, et al.The Journal of Physical Chemistry, 1988, 92(12), 3476. 38 Meissner D, Lauermann I, Memming R, et al.The Journal of Physical Chemistry, 1988, 92(12), 3484. 39 Morrison S R.Electrochemistry at semiconductor and oxidized metal electrodes, Plenum Press, 1980. 40 Butler M A, Ginley D S.Journal of the Electrochemical Society, 1978, 125(2),228. 41 Xiang Q, Yu J, Jaroniec M.Journal of the American Chemical Society, 2012, 134(15),6575. 42 Ratcliff E L, Lee P A, Armstrong N R.Journal of Materials Chemistry, 2010, 20(13),2672. 43 Geng W, Zhao X, Liu H, et al.Journal of Physical Chemistry C, 2013, 117(20),10536.