Study on photocatalytic nitrobenzene reduction to aniline over hierarchical flower-like Cu/TiO2
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摘要: 采用醇解溶剂热法制备金属Cu修饰的系列多级花状TiO2光催化剂（X% Cu/TiO2），并以可见光光催化硝基苯还原制苯胺为模型反应评价其光催化性能. 结果显示：3.3% Cu/TiO2光催化剂展现出优异的催化活性，可见光催化3 h硝基苯的转化率达到83%. 主要原因有两个方面：多级介孔结构增加了催化剂比表面积，促进了硝基苯吸附、扩散及其与催化剂的接触；金属Cu的引入降低了催化剂的带宽，增强了光生电子和空穴的分离能力，进而提升了其光催化性能. 此外，3.3% Cu/TiO2光催化剂表现出良好的稳定性，具有一定的潜在实用价值.Abstract: A series of metal Cu-modified hierarchical flower-like TiO2 catalysts (X% Cu/TiO2) was prepared by using an alcoholysis solvothermal method, and their photocatalytic performance were evaluated by using visible-light photocatalytic reduction of nitrobenzene to aniline as a model reaction. The results show that 3.3% Cu/TiO2 photocatalyst exhibits excellent catalytic activity, achieving 83% nitrobenzene conversion under visible-light irradiation for 3.0 h. There are two main attributions : firstly, the hierarchical structure enlarged the catalyst’s surface area and thus, improved the adsorption and diffusion of nitrobenzene and its contact efficiency with catalyst; secondly, the introduction of metal Cu reduced the catalyst’ energy band and enhanced the separation ability of photoelectron-hole, and thus enhanced the photocatalytic activity. In addition, 3.3% Cu/TiO2 also exhibits good stability and shows good potential in practical applications.
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Key words:
- photocatalysis /
- TiO2 /
- hierarchical structure /
- nitrobenzene reduction /
- metal modification
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图 2 不同催化剂的N2吸脱附等温线和孔径分布曲线
Figure 2. N2 adsorption-desorption isotherms and pore size distribution curves of different catalysts
图 7 不同催化剂的紫外可见漫反射光谱图
Figure 7. Uv-vis diffuse reflection spectra of different catalysts
图 8 不同催化剂的硝基苯光催化还原制苯胺的光催化活性
Figure 8. Photocatalytic activities of different catalysts for nitrobenzene reduction to aniline
图 9 不同催化剂的对位取代基硝基苯光催化还原制苯胺活性图
Figure 9. Photocatalytic activities of different catalysts for reduction nitrobenzene with various p-substituents to anilines
图 10 6次循环后3.3% Cu/TiO2的稳定性测试
Figure 10. Recycling test of 3.3% Cu/TiO2 after six cycles
表 1 不同催化剂的物理结构参数
Table 1. Physical parameters of different catalysts
催化剂 比表面积/
(m2·g−1)孔容/
(cm3·g−1)孔径/
nm晶粒尺寸/
nmTiO2 22 0.09 16 22 0.5% Cu/TiO2 28 0.10 14 22 2% Cu/TO2 28 0.11 15 21 3.3% Cu/TiO2 47 0.26 21 21 4.1% Cu/TiO2 39 0.24 23 21 5% Cu/TiO2 39 0.23 23 21 
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[1] KUMAR S, SURENDAR T, KUMAR B, et al. Synthesis of magnetically separable and recyclable g-C3N4-Fe3O4 hybrid nanocomposites with enhanced photocatalytic performance under visible-light irradiation[J] . Journal of Physical Chemistry C,2013,49:26135 − 26143. [2] CORMA A, SERNA P. Chemoselective hydrogenation of nitro-compounds with supported gold catalysts[J] . Science,2006,313:332 − 334. doi: 10.1126/science.1128383 [3] WU W, LIU G, XIE Q, et al. A simple and highly efficient route for the preparation of p-phenylenediamine by reducing 4-nitroaniline over commercial CdS visible light-driven photocatalyst in water[J] . Green Chemistry,2012,14:1705 − 1709. doi: 10.1039/c2gc35231a [4] 吴龙华, 孙佳怡, 雷金梅, 等. 掺铁二氧化钛类芬顿对染料废水的处理研究[J] . 科技风,2020,35:176 − 178. [5] YOO H, KIM J H. Photoactive TiO2/CuxO composite films for photocatalytic degradation of methylene blue pollutant molecules[J] . Advanced Powder Technology,2021,32(4):1287 − 1293. doi: 10.1016/j.apt.2021.02.031 [6] LU X F, SUN W J, LI J, et al. Spectroscopic investigations on the simulated solar light induced photodegradation of 4-nitrophenol by using three novel copper (II) porphyrin-TiO2 photocatalysts[J] . Spectrochemical Acta Part A: Molecular & Biomolecular Spectroscopy,2013,111:161 − 168. [7] LEE J H, KIM T, KIM E R, et al. Microwave-assisted synthesis of various Cu2O/Cu/TiO2 and CuxS/TiO2 composite nanoparticles towards visible-light photocatalytic applications[J] . Materials Chemistry and Physics,2021,259:123986. doi: 10.1016/j.matchemphys.2020.123986 [8] KUSIOR A, SYNOWIEC M, ZAKRZEWSKA K, et al. Surface-controlled photocatalysis and chemical sensing of TiO2, α-Fe2O3, and Cu2O nanocrystals[J] . Crystals,2019,9(3):163 − 214. doi: 10.3390/cryst9030163 [9] LIU J, LI X M, HE J, et al. Combining the photocatalysis and absorption properties of core-shell Cu-BTC@TiO2 microspheres: Highly efficient desulfurization of thiophenic compounds from fuel[J] . Materials (Basel),2018,11(11):2209 − 2227. doi: 10.3390/ma11112209 [10] BI F, EHSAN M F, LIU W, et al. Visible-light photocatalytic conversion of carbon dioxide into methane using Cu2O/TiO2 hollow nanospheres[J] . Chinese Journal of Chemistry,2013,33:112 − 118. [11] LI D F, WANG J G, XU F X, Et al. Mesoporous (001)-TiO2 nanocrystals with tailoring Ti3 + and surface oxygen vacancies for boosting photocatalytic selective conversion of aromatic alcohols[J] . Catalysis Science & Technology,2021,11(8):2939 − 2947. [12] YANG H G, ZENG H C. Preparation of hollow anatase TiO2 nanospheres via ostwald ripening[J] . Journal of Physical Chemistry B,2004,108:3492 − 3495. doi: 10.1021/jp0377782 [13] XU F X, WANG J G, LI D F, et al. Mesoporous (101)-TiO2 nanocrystals with tailoring Ti3 + and surface oxygen vacancies for boosting photocatalytic hydrogenation of nitrobenzenes[J] . Catalysis Science & Technology,2021,11:5147 − 5157. [14] TIAN F, ZHANG Y P, ZHANG J, et al. Raman spectroscopy: A new approach to measure the percentage of anatase TiO2 exposed (001) facets[J] . The Journal Physical Chemistry C,2012,116:7515 − 7519. doi: 10.1021/jp301256h [15] HUANG C J, YE W Q, LIU Q W, et al. Dispersed Cu2O octahedrons on h-BN nanosheets for p-nitrophenol reduction[J] . ACS Applied Materials & Interfaces,2014,6(16):14469 − 14476. [16] KAUR R, PAL B. Cu nanostructures of various shapes and sizes as superior catalysts for nitro-aromatic reduction and co-catalyst for Cu/TiO2 photocatalysis[J] . Applied Catalysis A: General,2015,491:28 − 36. doi: 10.1016/j.apcata.2014.10.035 [17] HU Y H. A highly efficient photocatalyst-hydrogenated black TiO2 for the photocatalytic splitting of water[J] . Angewandte Chemie International Edition,2012,51:12410 − 12412. doi: 10.1002/anie.201206375 [18] BABU S G, VINOTH R, KUMAR D P, et al. Influence of electron storing, transferring and shuttling assets of reduced graphene oxide at the interfacial copper doped TiO2 p-n heterojunction for increased hydrogen production[J] . Nanoscale,2015,7(17):7849 − 7857. doi: 10.1039/C5NR00504C [19] WANG J G, LIANG H, ZHANG C, et al. Bi2WO6-x nanosheets with tunable Bi quantum dots and oxygen vacancies for photocatalytic selective oxidation of alcohols[J] . Applied Catalysis B: Environmental,2019,256:117874. doi: 10.1016/j.apcatb.2019.117874 [20] WANG J G, RAO P H, AN W, et al. Boosting photocatalytic activity of Pd decorated TiO2 nanocrystal with exposed (001) facets for selective alcohol oxidations[J] . Applied Catalysis B: Environmental,2016,195:41 − 48. [21] GE Y H, LUO H, HUANG J R, et al. Visible-light-active TiO2 photocatalyst for efficient photodegradation of organic dyes[J] . Optical Materials,2021,115:111058. doi: 10.1016/j.optmat.2021.111058 [22] CHEN X B, MAO S S. Titanium dioxide nanomaterials: synthesis, properties, modifications, and applications[J] . Chemical Reviews,2007,107(7):2891 − 2959. doi: 10.1021/cr0500535 [23] XU C, YANG F, DENG B J, et al. Ti3C2/TiO2 nanowires with excellent photocatalytic performance for selective oxidation of aromatic alcohols to aldehydes[J] . Journal of Catalysis,2019,383:1 − 12. -
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