3D flower-shaped MoS2/O-g-C3N4 Z-type heterojunction enhances the photocatalyst degradation of bisphenol A
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摘要: 光催化降解是一种很有应用前景的污染物处理方法。采用溶剂热法制备了3D/2D二硫化钼负载氧掺杂石墨相氮化碳(MoS2/O-g-C3N4)复合材料,通过XRD、XPS、SEM、TEM、FTIR和PL等表征了MoS2与O-g-C3N4之间Z型异质结的成功构建。在模拟太阳光下,当MoS2的负载量为0.2%时,MoS2/O-g-C3N4的光催化活性最高,双酚A (BPA)的降解率为92.6%,是纯g-C3N4的7倍。此外,MoS2和O-g-C3N4之间界面的紧密接触和相互的协同效应,显著增强了光催化反应活性位点和可见光吸收能力,有效提高了光生载流子的分离。根据液相质谱联用仪(LC-MS)和自由基捕获实验,提出了0.2%MoS2/O-g-C3N4异质结复合材料降解BPA可能的光催化降解机制。本研究为制备高效异质结光催化剂提供了新的方法。Abstract: Photocatalytic degradation was considered as a promising strategy for the elimination of hazardousorganic pollutants. In this work, a binary 3D/2D molybdenum disulfide supported oxygen-doped graphite carbon nitride (MoS2/O-g-C3N4) heterojunctions was successfully fabricated by using a facile hydrothermal strategy. Meanwhile, the as-prepared photocatalysts were characterized by XRD, XPS, SEM, TEM, FTIR and PL. By these characterized observed the formation of Z-type heterojunction between MoS2 and O-g-C3N4. Under visible light irradiation, when the loading of MoS2 was 0.2%, MoS2/O-g-C3N4 exhibited better photocatalytic activity, and the degradation rate of bisphenol A (BPA) is 92.6%, which is 7 times higher than that of pure g-C3N4. In addition, the close contact and mutual synergistic effect of the interface between MoS2 and O-g-C3N4 significantly enhance the photocatalytic reaction active sites and visible light absorption capacity, and effectively improve the separation of photogenerated carriers. Using liquid chromatography-mass spectrometry technology (LC-MS) and capturing experimental results, the possible photocatalytic mechanism of the 0.2%MoS2/O-g-C3N4 heterojunction composite material degrading crystal violet were proposed. This research provides a new method for the preparation of high-efficiency heterojunction photocatalysts.
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Key words:
- MoS2 /
- graphite carbon nitride /
- Z-type heterojunction /
- photocatalysis /
- mutual synergistic
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图 1 (a) 石墨相氮化碳(g-C3N4)、氧掺杂g-C3N4 (O-g-C3N4)、MoS2和X%MoS2/O-g-C3N4的XRD图谱(插图为g-C3N4和O-g-C3N4的放大图);g-C3N4 (b)、O-g-C3N4 (c) 和0.2%MoS2/O-g-C3N4 (d) 的TEM图像
Figure 1. (a) XRD patterns of graphite carbon nitride (g-C3N4), oxygen-doped g-C3N4 (O-g-C3N4), MoS2 and X%MoS2/O-g-C3N4 (Illustration is an enlarged view of g-C3N4 and O-g-C3N4); TEM images of g-C3N4 (b), O-g-C3N4 (c) and 0.2%MoS2/O-g-C3N4(d)
图 2 (a) 0.2%MoS2/O-g-C3N4的XPS全谱;(b) g-C3N4、O-g-C3N4、MoS2和0.2%MoS2/O-g-C3N4的C1s谱;(c) O-g-C3N4和0.2%MoS2/O-g-C3N4的N1s谱;(d) g-C3N4、O-g-C3N4和0.2%MoS2/O-g-C3N4的O1s谱;(e) MoS2和0.2%MoS2/O-g-C3N4的Mo3d谱;(f) MoS2和0.2%MoS2/O-g-C3N4的S2p谱
Figure 2. (a) XPS survey of 0.2%MoS2/O-g-C3N4; (b) C1s spectra of g-C3N4, O-g-C3N4, MoS2 and 0.2%MoS2/O-g-C3N4; (c) N1s spectra of O-g-C3N4 and 0.2%MoS2/O-g-C3N4; (d) O1s spectra of g-C3N4, O-g-C3N4 and 0.2%MoS2/O-g-C3N4; (e) Mo3d spectrum of MoS2 and 0.2%MoS2/O-g-C3N4; (f) S2p spectra of MoS2 and 0.2%MoS2/O-g-C3N4
图 5 (a) g-C3N4、O-g-C3N4和X%MoS2/O-g-C3N4的UV-vis DRS光谱图;(b) O-g-C3N4、MoS2和0.2%MoS2/O-g-C3N4的(αhv)1/2-hv曲线;(c) g-C3N4、O-g-C3N4和0.2%MoS2/O-g-C3N4的PL光谱图;(d) g-C3N4、O-g-C3N4和0.2%MoS2/O-g-C3N4的电化学阻抗图
Figure 5. (a) UV-vis DRS spectra of g-C3N4, O-g-C3N4 and 0.2%MoS2/O-g-C3N4; (b) Plots of (αhv)1/2 versus band-gap energy (hv) of O-g-C3N4, MoS2 and 0.2%MoS2/O-g-C3N4; (c) PL spectra of g-C3N4, O-g-C3N4 and 0.2%MoS2/O-g-C3N4; (d) Nyquist plots of EIS of g-C3N4, O-g-C3N4 and 0.2%MoS2/O-g-C3N4
图 6 (a) g-C3N4、O-g-C3N4、MoS2和X%MoS2/O-g-C3N4的光催化降解图;(b) g-C3N4、O-g-C3N4、MoS2和X%MoS2/O-g-C3N4的降解动力学曲线;(c) 0.2%MoS2/O-g-C3N4催化剂循环实验;(d) 0.2%MoS2/O-g-C3N4循环前后的XRD图谱;(e) 0.2%MoS2/O-g-C3N4循环前后的FTIR图谱
Figure 6. Photocatalytic degradation diagrams of g-C3N4, O-g-C3N4, MoS2 and X%MoS2/O-g-C3N4; (b) Degradation kinetic curves of g-C3N4, O-g-C3N4, MoS2 and X%MoS2/O-g-C3N4; (c) 0.2%MoS2/O-g-C3N4 catalyst cycle test; (d) XRD patterns before and after cycles of 0.2%MoS2/O-g-C3N4; (e) FTIR spectra before and after cycles of 0.2%MoS2/O-g-C3N4
C—Bisphenol A (BPA) concentration after t time; C0—BPA concentration at the initial time; K—Speed constant; R2—Fit coefficient
表 1 g-C3N4、O-g-C3N4和0.2%MoS2/O-g-C3N4的质构特性
Table 1. Textural properties of g-C3N4, O-g-C3N4 and 0.2%MoS2/O-g-C3N4
Sample SBET/(m2·g−1) Pore size/nm g-C3N4 14.94 0.092 O-g-C3N4 48.28 0.313 0.2%MoS2/O-g-C3N4 39.89 0.228 -
[1] HASSAN N S, JALIL A A, TRIWAHYONO S, et al. Synergistic effect of microwave rapid heating and weak mineralizer on silica-stabilized tetragonal zirconia nanoparticles for enhanced photoactivity of Bisphenol A[J]. Journal of Molecular Liquids,2018,261:423-430. doi: 10.1016/j.molliq.2018.04.068 [2] KUMAR A, RANA A, SHARMA G, et al. Recentadvances in nano-Fenton catalytic degradation of emerging pharmaceutical contaminants[J]. Journal of Molecular Liquids,2019,290:111177. doi: 10.1016/j.molliq.2019.111177 [3] BAI X, YANG L, HAGFELDT A, et al. D35-TiO2 nano-crystalline film as a high performance visible-light photocatalyst towards the degradation of bisphenol A[J]. Chemical Engineering Journal,2019,355:999-1010. doi: 10.1016/j.cej.2018.08.061 [4] LIANG P, MENG D D, LIANG Y, et al. Cation deficiency tuned LaCoO3-δ perovskite for peroxymonosulfate activation towards bisphenol A degradation[J]. Chemical Engineering Journal,2020,409(2):128196. [5] CONG Y Q, ZHANG W H, DING W, et al. Fabrication of electrochemically-modified BiVO4-MoS2-Co3O4 compo-site film for bisphenol A degradation[J]. Journal of Environmental Sciences,2021,102:341-351. doi: 10.1016/j.jes.2020.09.027 [6] YANG Y, ZENG Z T, ZHANG C, et al. Construction of iodine vacancy-rich BiOI/Ag@AgI Z-scheme heterojunctio n photocatalysts for visible-light-driven tetracycline degradation: Transformation pathways and mechanism insight[J]. Chemical Engineering Journal,2018,349:808-821. doi: 10.1016/j.cej.2018.05.093 [7] LIU Y Z, XU X Y, ZHANG J Q, et al. Flower-like MoS2 on graphitic carbon nitride for enhanced photocatalytic and electrochemical hydrogen evolutions[J]. Applied Catalysis B: Environmental,2018,239:334-344. doi: 10.1016/j.apcatb.2018.08.028 [8] 张家晶 郑永杰, 金春雪, 等. g-C3N4基光催化剂改性的研究进展[J]. 现代化工, 2021, 41(3):42-47.ZHANG Jiajing, ZHENG Yongjie, JIN Chunxue, et al. Research progress on modification g-C3N4-based photocatalyst[J]. Modern Chemical Industry,2021,41(3):42-47(in Chinese). [9] YU W W, ZHANG T, ZHAO Z K. Garland-like intercalated carbon nitride prepared by an oxalic acid-mediated assembly strategy for highly-efficient visible-light-driven photoredox catalysis[J]. Applied Catalysis B: Environmental,2020,278:119342. doi: 10.1016/j.apcatb.2020.119342 [10] HUMAYUNA M, FU Q Y, ZHENG Z P, et al. Improved visible-light catalytic activities of novel Au/P-doped g-C3N4 photocatalyst for solar fuel production and mechanism[J]. Applied Catalysis A General,2018,568:139-147. doi: 10.1016/j.apcata.2018.10.007 [11] XU Q, CHENG B, YU J, et al. Making co-condensed amorphous carbon/g-C3N4 composites with improved visible-light photocatalytic H2 production performance using Pt as cocatalyst[J]. Carbon,2017,118:241-249. doi: 10.1016/j.carbon.2017.03.052 [12] HAK C H, SIM L C, LEONG K H, et al. M/g-C3N4 (M=Ag, Au, and Pd) composite: Synthesis via sunlight photodepo-sition and application towards the degradation of bisphenol A[J]. Environmental Science and Pollution Research,2018,25(25):25401-25412. [13] MO Z, XU H, SHE X J, et al. Constructing Pd/2D-C3N4 composites for efficient photocatalytic H2 evolution through nonplasmon induced bound electrons[J]. Applied Surface Science,2019,467:151-157. [14] MO Z, XU H, CHEN Z G, et al. Construction of MnO2/monolayer g-C3N4 with Mn vacancies for Z-scheme overall water splitting[J]. Applied Catalysis B: Environmental,2019,241:452-460. doi: 10.1016/j.apcatb.2018.08.073 [15] LI Y F, ZHOU M H, CHENG B, et al. Recent advances in g-C3N4-based heterojunction photocatalysts[J]. Journal of Materials Science & Technology,2020,56(21):1-17. [16] JOURSHABANI M, LEE B K, SHARIATINIA Z. From traditional strategies to Z-scheme configuration in graphitic carbon nitride photocatalysts: recent progress and future challenges[J]. Applied Catalysis B: Environmental,2020,276:119157. doi: 10.1016/j.apcatb.2020.119157 [17] ZHU Y, CHEN Z H, GAO Y W, et al. General synthesis of carbon and oxygen dual-doped graphitic carbon nitride via copolymerization for non-photochemical oxidation of organic pollutant[J]. Journal of Hazardous Materials,2020,394:122578. doi: 10.1016/j.jhazmat.2020.122578 [18] FANG G, LI M Y, SHEN H F, et al. Enhanced photocatalytic characteristics and low selectivity of a novel Z-scheme TiO2/g-C3N4/Bi2WO6 heterojunction under visible light[J]. Materials Science in Semiconductor Processing,2021,121:105374. doi: 10.1016/j.mssp.2020.105374 [19] GUO L, YANG Z, MARCUS K, et al. MoS2/TiO2 heterostructures as nonmetal plasmonic photocatalysts for highly efficient hydrogen evolution[J]. Energy Environment Science,2018,11(1):106-114. doi: 10.1039/C7EE02464A [20] ZI X Y, WAN J, YANG X, et al. Vacancy-rich 1T-MoS2 monolayer confined to MoO3 matrix: An interface-engineered hybrid for efficiently electrocatalytic conversion of nitrogen to ammonia[J]. Applied Catalysis B: Environmental, 2021, 286: 119870. [21] LIU Y Z, ZHANG H Y, KE J, et al. 0D (MoS2)/2D (g-C3N4) heterojunctions in Z-scheme for enhanced photocatalytic and electrochemical hydrogen evolution[J]. Applied Catalysis B: Environmental,2018,228:64-74. doi: 10.1016/j.apcatb.2018.01.067 [22] ZHANG D D, ZHANG G G, HOU Y D, et al. Layering MoS2 on soft hollow g-C3N4 nanostructures for photocatalytic hydrogen evolution[J]. Applied Catalysis A Generals,2016,521:2-8. doi: 10.1016/j.apcata.2015.10.037 [23] YAN Y, BAO Y X, GE X, et al. Ultrathin MoS2 nanoplates with rich active sites as highly efficient catalyst for hydrogen evolution[J]. ACS Applied Material Interfaces,2013,5(24):12794-12798. doi: 10.1021/am404843b [24] LU D Z, WANG H M, ZHAO X N, et al. Highly efficient visible-light-induced photoactivity of Z-scheme g-C3N4/Ag/MoS2 ternary photocatalysts for organic pollutant degradation and production of hydrogen[J]. ACS Sustainable Chemistry & Engineering,2017,5(2):1436-1445. [25] XU Q L, ZHU B C, CHENG B, et al. Photocatalytic H2 evolution on graphdiyne/g-C3N4 hybrid nanocomposites[J]. Applied Catalysis B: Environmental,2019,255:117770. doi: 10.1016/j.apcatb.2019.117770 [26] XIE J F, ZHANG H, LI S, et al. Defect-rich MoS2 ultrathin nanosheets with additional active edge sites for enhanced electrocatalytic hydrogen evolution.[J]. Advanced Materials,2013,25(40):5807-5813. doi: 10.1002/adma.201302685 [27] ZHANG S, LIU Y, GU P C, et al. Enhanced photodegradation of toxic organic pollutants using dual-oxygen-doped porous g-C3N4: Mechanism exploration from both experimental and DFT studies[J]. Applied Catalysis B: Environmental,2019,248:1-10. doi: 10.1016/j.apcatb.2019.02.008 [28] WU Z S, HE X F, XUE Y T, et al. Cyclodextrins grafted MoS2/g-C3N4 as high-performance photocatalysts for the removal of glyphosate and Cr (VI) from simulated agricultural runoff[J]. Chemical Engineering Journal,2020,399:125747. doi: 10.1016/j.cej.2020.125747 [29] JALEEL U, DEVI K, MADHUSHREE R, et al. Statistical and experimental studies of MoS2/g-C3N4/TiO2: A ternary Z-scheme hybrid composite[J]. Journal of Materials Science,2021,56(11):1-23. [30] DENG Y C, TANG L, ZENG G M, et al. Insight into highly efficient simultaneous photocatalytic removal of Cr(VI) and 2, 4-diclorophenol under visible light irradiation by phosphorus doped porous ultrathin g-C3N4 nanosheets from aqueous media: Performance and reaction mechanism[J]. Applied Catalysis B: Environmental,2017,203:343-354. doi: 10.1016/j.apcatb.2016.10.046 [31] LI G, LI Y J, LIU H, et al. Architecture of graphdiyne nanoscale films[J]. Chemical Communications,2010,46(19):3256-3258. doi: 10.1039/b922733d [32] SHE X J, WU J J, ZHONG J, et al. Oxygenated monolayer carbon nitride for excellent photocatalytic hydrogen evolution and external quantum efficiency[J]. Nano Energy,2016,27:138-146. doi: 10.1016/j.nanoen.2016.06.042 [33] XUE M Q, NI G H, PAN A X, et al. 2D/2D heterostructure of flower-like MoS2 nanospheres anchored on g-C3N4 nanosheets for reducing friction and wear[J]. Chalcogenide Letters,2021,18(2):91-102. [34] WEI Z Y, SHEN X Y, JI Y X, et al. Synthesis of novel MoS2/g-C3N4 nanocomposites for enhanced photocatalytic activity[J]. Journal of Materials Science Materials in Electronics,2020,31(18):70-73. [35] REDDY K R, REDDY C V, NADAGOUDA M N, et al. Polymeric graphitic carbon nitride (g-C3N4)-based semiconducting nanostructured materials: Synthesis methods, properties and photocatalytic applications[J]. Journal of Environmental Management,2019,238:25-40. [36] LI G Q, SHI J, ZHANG G D, et al. The facile synthesis of graphitic carbon nitride from amino acid and urea for photocatalytic H2 production[J]. Research on Chemical Intermediates,2017,43(9):5137-5152. doi: 10.1007/s11164-017-3041-1 [37] YANG W, WANG Y. Enhanced electron and mass transfer flow-through cell with C3N4-MoS2 supported on three-dimensional graphene photoanode for the removal of antibiotic and antibacterial potencies in ampicillin wastewater[J]. Applied Catalysis B: Environmental,2020,282:119574. [38] JIANG Z F, QIAN K, ZHU C Z, H. et al. Carbon nitride coupled with CdS-TiO2 nanodots as 2D/0D ternary composite with enhanced photocatalytic H2 evolution: A novel efficient three-level electron transfer process[J]. Applied Catalysis B: Environmental, 2017, 210: 194-204. [39] YANG B, ZHAO J J, YANG W D, et al. A step-by-step synergistic stripping approach toward ultra-thin porous g-C3N4 nanosheets with high conduction band position for photocatalystic CO2 reduction[J]. Journal of Colloid and Interface Science,2021,589(12):179-186. [40] UDDIN A, MUHMOOD T, GUO Z C, et al. Hydrothermal synthesis of 3D/2D heterojunctions of ZnIn2S4/oxygen doped g-C3N4 nanosheet for visible light driven photocatalysis of 2, 4-dichlorophenoxyacetic acid degradation[J]. Journal of Alloys and Compounds,2020,845:156206. doi: 10.1016/j.jallcom.2020.156206 [41] ZHANG J J, ZHENG Y J, ZHENG H S, et al. A 2D/3D g-C3N4/BiOI heterostructure nano-sphere with oxygen-doped for enhanced visible light-driven photocatalytic activity in environmental remediation [J]. Journal of Alloys and Compounds,2022,897: 163044. doi: 10.1016/j.jallcom.2021.163044 [42] JIANG L B, YUAN X Z, ZENG G M, et al. Phosphorus- and sulfur-codoped g-C3N4: Facile preparation, mechanism insight, and application as efficient photocatalyst for tetracycline and methyl orange degradation under visible light irradiation[J]. ACS Sustainable Chemical Engineering,2017,5(7):5831-5841. doi: 10.1021/acssuschemeng.7b00559 [43] XUE Z, ZHANG X Y, QIN J Q, et al. Constructing MoS2/g-C3N4 heterojunction with enhanced oxygen evolution reaction activity: A theoretical insight[J]. Applied Surface Science,2020,510:145489. doi: 10.1016/j.apsusc.2020.145489 [44] TIAN S C, ZHANG X H, ZHANG Z H. Capacitive deionization with MoS2/g-C3N4 electrodes[J]. Desalination,2020,479:114348. doi: 10.1016/j.desal.2020.114348 [45] HE D H, ZHANG C, ZENG G M, et al. A multifunctional platform by controlling of carbon nitride in the core-shell structure: From design to construction, and catalysis applications[J]. Applied Catalysis B: Environmental,2019,258:117957. doi: 10.1016/j.apcatb.2019.117957 [46] YANG S J, QIU X J, JIN P K, et al. MOF-templated synthesis of CoFe2O4 nanocrystals and its coupling with peroxymonosulfate for degradation of bisphenol A[J]. Chemical Engineering Journal,2018,353:329-339. doi: 10.1016/j.cej.2018.07.105 [47] XU L, YANG L, JOHANSSO E M J, et al. Photocatalytic activity and mechanism of bisphenol a removal over TiO2-x/rGO nanocomposite driven by visible light[J]. Chemical Engineering Journal,2018,350:1043-1055. doi: 10.1016/j.cej.2018.06.046