Photocatalytic degradation mechanism of mefenamic acid by N-doped carbon quantum dots loaded on TiO2
ZHANG Qian-xin1, WANG Feng-liang1, XIE Zhi-jie1, SU Yue-han1, CHEN Ping1, LÜ Wen-ying1, YAO kun1, LIU Hai-jin2, LIU Guo-guang1
1. School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006 China;
2. School of Chemistry and Environmental Science, Henan Normal University, Xinxiang 453007 China
The water-soluble N-doped carbon quantum dots (NCQDs) were successfully prepared by hydrothermal method, which was used to dope titanium dioxide to form P25/NCQDs composite materials. The morphology, elemental and catalytic activity of NCP composites were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and UV-Vis Absorption Spectroscopy (UV-vis). The results show that the NCQDs was successfully attached to the surface of P25. NCQDs could let the absorption spectrum of P25 redshift and enhance the light absorption range of P25. The photocatalytic degradation of mefenamic acid (MEF) by NCP was 6.4 times higher than bare P25 under the same conditions. The effects of NCP composite on the photocatalytic degradation of MEF was also studied. The pH was favorable for the degradation of MEF in alkaline condition. The electron paramagnetic resonance (EPR) results show that the hydroxyl radical was the main active substance in the NCP system. The contribution rate of ·OH for MEF degradation was 82.9% through the quenching experiment by add isopropanol as scavenger.
Evgenidou E N, Konstantinou I K, Lambropoulou D A. Occurrence and removal of transformation products of PPCPs and illicit drugs in wastewaters:A review[J]. Science of the Total Environment, 2015,505:905-926.
[2]
Oliver D. Diphenylamine and derivatives in the environment:a review.[J]. Chemosphere, 2003,53(8):809-18.
[3]
Hilton M J, Thomas K V. Determination of selected human pharmaceutical compounds in effluent and surface water samples by high-performance liquid chromatography-electrospray tandem mass spectrometry.[J]. Journal of Chromatography A, 2003, 1015(1/2):129-41.
[4]
Tauxe-Wuersch A, Alencastro L F D, Grandjean D, et al. Occurrence of several acidic drugs in sewage treatment plants in Switzerland and risk assessment.[J]. Water Research, 2005, 39(9):1761-1772.
[5]
Suwalsky, Mario Manrique-Moreno M, Howe J, et al. Molecular interactions of mefenamic acid with lipid bilayers and red blood cells.[J]. Journal of the Brazilian Chemical Society, 2011,22(12):2243-2249.
Wang A N, Teng Y, Hu X F, et al. Diphenylarsinic acid contaminated soil remediation by titanium dioxide (P25) photocatalysis:Degradation pathway, optimization of operating parameters and effects of soil properties.[J]. Science of the Total Environment, 2016,541:348-355.
[8]
Sakthivel S, Kisch H. Photocatalytic and Photoelectrochemical Properties of Nitrogen-Doped Titanium Dioxide[J]. Chemphyschem A European Journal of Chemical Physics & Physical Chemistry, 2003,4(5):487-90.
Wu C G, Chao C C, Kuo F T. Enhancement of the photo catalytic performance of TiO2 catalysts via transition metal modification[J]. Catalysis Today, 2004,97(s2-3):103-112.
Li H, He X, Liu Y, et al. Synthesis of fluorescent carbon nanoparticles directly from active carbon via a one-step ultrasonic treatment[J]. Materials Research Bulletin, 2011,46(1):147-151.
[13]
Hengchao Z, Hai M, Suoyuan L, et al. Fe2O3/carbon quantum dots complex photocatalysts and their enhanced photocatalytic activity under visible light[J]. Dalton Transactions, 2011,40(41):10822-5.
[14]
Ma S. A facile route for the preparation of ZnO/C composites with high photocatalytic activity and adsorption capacity[J]. Crystengcomm, 2014,16(21):4478-4484.
[15]
Wang J, Gao M, Ho G W. Bidentate-complex-derived P25/carbon dot photocatalysts:in situ synthesis, versatile heterostructures, and enhanced H2 evolution[J]. J.mater.chem.a, 2014,2(16):5703-5709.
[16]
Zhang Y Q, Ma D K, Zhang Y G, et al. N-doped carbon quantum dots for TiO2-based photocatalysts and dye-sensitized solar cells[J]. Nano Energy, 2013,2(5):545-552.
[17]
李海涛.荧光纳米碳点的合成及其催化应用研究[D]. 苏州大学, 2013.
[18]
Gong J. A novel rapid and green synthesis of highly luminescent carbon dots with good biocompatibility for cell imaging[J]. New Journal of Chemistry, 2014,38(4):1376-1379.
[19]
Wang C, Wu X, Li X, et al. Upconversion fluorescent carbon nanodots enriched with nitrogen for light harvesting[J]. Journal of Materials Chemistry, 2012,22(31):15522-15525.
[20]
Jing W U, Zhou W F, Pan G, et al. Preparation and properties on rare-earth element praseodymium doped nano-titanium dioxide photocatalyst[J]. Journal of Functional Materials, 2010,41(4):562-530.
YANG, Shi-ying, Li-ping, et al. Reaction site and mechanism in the UV or visible light induced P25photodegradation of Orange G[J]. 环境科学学报(英文版), 2006,18(1):61381V-61381V-8.
[23]
Ji Y, Zhou L, Ferronato C, et al. Photocatalytic degradation of atenolol in aqueous titanium dioxide suspensions:Kinetics, intermediates and degradation pathways[J]. Journal of Photochemistry & Photobiology A Chemistry, 2013,254(7):35-44.
[24]
Raghava Reddy K, Gomes V G, Hassan M. Carbon functionalized P25nanofibers for high efficiency photocatalysis[J]. Materials Research Express, 2014,1(1).
[25]
Chang E E, Liu T Y, Huang C P, et al. Degradation of mefenamic acid from aqueous solutions by the ozonation and O3/UV processes[J]. Separation & Purification Technology, 2012,98(39):123-129.
[26]
Xiao R, Noerpel M, Luk H L, et al. Thermodynamic and kinetic study of ibuprofen with hydroxyl radical:A density functional theory approach[J]. International Journal of Quantum Chemistry, 2014,114(1):74-83.
[27]
Khodja A A, Lavedrine B, Richard C, et al. Photocatalytic degradation of metoxuron in aqueous suspensions of. Analytical and kinetic studies[J]. International Journal of Photoenergy, 2002,4(4):147-151.
[28]
Haque M M, Mohd M, Bahnemann D W. Semiconductormediated Photocatalyzed degradation of a herbicide derivative, chlorotoluron, in aqueous suspensions[J]. Environmental Science & Technology, 2006,40(15):4765-70.
[29]
Edhlund B L, Arnold W A, Kristopher M N. Aquatic photochemistry of nitrofuran antibiotics[J]. Environmental Science & Technology, 2006,40(17):5422-7.
[30]
Shan Z, Yong C, O'Shea K E. P25 photocatalytic degradation of phenylarsonic acid[J]. Journal of Photochemistry & Photobiology A Chemistry, 2010,5(1):61-68.
[31]
Rao Y F, Chu W. Reaction mechanism of linuron degradation in P25 suspension under visible light irradiation with the assistance of H2O2.[J]. Environmental Science & Technology, 2009,43(16):6183-6189.
[32]
Jungwon K, Chul Wee L, Wonyong C. Platinized WO3 as an environmental photocatalyst that generates OH radicals under visible light[J]. Environmental Science & Technology, 2010, 44(17):6849-54.
[33]
Park H, Park Y, Kim W, et al. Surface modification of P25 photocatalyst for environmental applications[J]. Journal of Photochemistry & Photobiology C Photochemistry Reviews, 2013,15(3):1-20.
[34]
Sun Y, Pignatello J J. Evidence for a surface dual hole-radical mechanism in the titanium dioxide photocatalytic oxidation of 2,4-D.[J]. Environmental Science & Technology, 1995,29(29):2065-72.
[35]
Chen P, Wang F, Chen Z F, et al. Study on the photocatalytic mechanism and detoxicity of gemfibrozil by a sunlight-driven TiO2/carbon dots photocatalyst:The significant roles of reactive oxygen species[J]. Applied Catalysis B Environmental, 2017,204:250-259.
[36]
Chen Y, Yang S, Wang K, et al. Role of primary active species and P25 surface characteristic in UV-illuminated photodegradation of Acid Orange 7[J]. Journal of Photochemistry & Photobiology A Chemistry, 2005,172(1):47-54.
[37]
Lee A T, Hoffmann M R. Chemical mechanism of inorganic oxidants in the P25/UV process:increased rates of degradation of chlorinated hydrocarbons[J]. Environmental Science & Technology, 1995,29(10):2567-2573.
[38]
Chen M G, Zhang F, Cui C, et al. Treatment of wastewater from paracetamol factory by using non-thermal plasma and active carbon[C]//Materials for Renewable Energy & Environment (ICMREE), 2011International Conference on, 2011:138-9.
[39]
Buxton G V, Greenstock C L, Helman W P, et al. Critical Review of rate constants for reactions of hydrated electrons, hydrogen atoms and hydroxyl radicals (OH/O- in Aqueous Solution[J]. Journal of Physical & Chemical Reference Data, 1988,17(2):513-886.
[40]
Jungho R, Wonyong C. Substrate-specific photocatalytic activities of P25and multiactivity test for water treatment application.[J]. Environmental Science & Technology, 2008, 42(1):294-300.
[41]
Hapeshi E, Achilleos A, Vasquez M I, et al. Drugs degrading photocatalytically:Kinetics and mechanisms of ofloxacin and atenolol removal on titania suspensions[J]. Water Research, 2010, 44(6):1737-1746.
[42]
Chen P, Wang F, Zhang Q, et al. Photocatalytic degradation of clofibric acid by gC3N4/P25 composites under simulated sunlight irradiation:The significant effects of reactive species.[J]. Chemosphere, 2017,172:193-200.
Han Y, Huang H, Zhang H, et al. Carbon Quantum Dots with Photoenhanced Hydrogen-Bond Catalytic Activity in Aldol Condensations[J]. Acs Catalysis, 2016,4(3):781-787.
[45]
Zhang Y Q, Ma D K, Zhang Y G, et al. N-doped carbon quantum dots for P25-based photocatalysts and dye-sensitized solar cells[J]. Nano Energy, 2013,2(5):545-552.
[46]
Yu H. ZnO/carbon quantum dots nanocomposites:one-step fabrication and superior photocatalytic ability for toxic gas degradation under visible light at room temperature[J]. New Journal of Chemistry, 2012,36(36):1031-1035.
[47]
Hai M, Zheng M, Yang L, et al. Large scale electrochemical synthesis of high quality carbon nanodots and their photocatalytic property[J]. Dalton Transactions, 2012,41(31):9526-31.
[48]
Zhang X, Li X, Qin W. Investigation of the catalytic activity for ozonation on the surface of NiO nanoparticles[J]. Chemical Physics Letters, 2009,479(s4-6):310-315.
