Citation: HE Jie, FAN Yi-Ning. Dispersion and Acidity of Niobia on Nb₂O₅/γ-Al₂O₃[J]. Acta Physico-Chimica Sinica, ;2010, 26(03): 679-684. doi: 10.3866/PKU.WHXB20100233 shu

Dispersion and Acidity of Niobia on Nb₂O₅/γ-Al₂O₃

HE Jie ,
FAN Yi-Ning

1.
School of Chemical Engineering, Anhui University of Science and Technology, Huainan 232001, Anhui Province, P. R. China; Key Laboratory of Mesoscopic Chemistry of the Ministry of Education, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, P. R. China

Received Date: 28 August 2009
Available Online: 4 January 2010

Supported niobium pentoxide materials are effective catalysts for a variety of reactions. Nb2O5/γ-Al2O3 catalysts with different Nb2O5 loadings were prepared by aqueous solution impregnation using niobium oxalate as a precursor on γ-Al2O3. The samples were characterized with respect to the dispersion state of the niobium oxide species on γ-Al2O3 by X-ray power diffraction (XRD) and laser Raman spectroscopy (LRS). The nature of the surface acidity was investigated using Fourier-transform infrared spectroscopy of pyridine adsorption (Py-IR). The catalytic activity of the as-prepared catalysts was evaluated by the condensation reaction of iso-butene (IB) and iso-butyraldehyde (IBA) to form 2,5-dimethyl-2,4-hexadiene (DMHD). Results reveal that the dispersion capacity (ΓNb) of Nb on γ-Al2O3 is about 7.6 μmol·m-2. This value is almost identical to the density of the octahedral vacant sites of the preferentially exposed (110) plane (7.5 μmol·m-2) on the surface of the γ-Al2O3 support. Additionally, the“incorporated model”suggests that Nb5+ cations are located on the vacant sites of the (110) plane on γ-Al2O3. These results suggest that isolated niobia (NbOx) species are present and are bound to the surface of the γ-Al2O3 support through Nb—O—Al bonds at a loading well below that corresponding to monolayer dispersion. This is consistent with the result from LRS. The formation of isolated NbOx species, which binds to the surface of the support through Nb—O—Al bonds, causes a decrease in the amount of surface Lewis acid sites (LAS) on the Nb2O5/γ-Al2O3 catalysts. With an increase in Nb2O5 loading, polymeric NbOx species are formed by the Nb—O—Nb bridging of neighboring isolated NbOx species and Bronsted acid sites (BAS) are generated. We found that the catalytic activity towards the condensation reaction of IB and IBA to form DMHD increased because the amount and strength of the Bronsted acid sites increased as the number of polymeric niobia species increased. When the loading exceeds the monolayer dispersion capacity, the catalytic activity (turnover frequency (TOF) of DMHD) decreased because of the formation of the three-dimensional NbOx species. Additionally, the selectivity of DMHD decreased because of an increase in the strength of the Bronsted acid sites. We suggest that the strength of the Bronsted acid sites are related to the state of NbOx on the surface of the Nb2O5/γ-Al2O3 catalysts.
- Surface acidity,
- Nb2O5/γ-Al2O3,
- NbOx surface species,
- Olefin-aldehyde condensation
1. [1]
  Weihan Zhang , Menglu Wang , Ankang Jia , Wei Deng , Shuxing Bai . 表面硫物种对钯-硫纳米片加氢性能的影响. Acta Physico-Chimica Sinica, 2024, 40(11): 2309043-. doi: 10.3866/PKU.WHXB202309043
2. [2]
  Heng Chen , Longhui Nie , Kai Xu , Yiqiong Yang , Caihong Fang . 两步焙烧法制备大比表面积和结晶性增强超薄g-C₃N₄纳米片及其高效光催化产H₂O₂. Acta Physico-Chimica Sinica, 2024, 40(11): 2406019-. doi: 10.3866/PKU.WHXB202406019
3. [3]
  Chuanming GUO , Kaiyang ZHANG , Yun WU , Rui YAO , Qiang ZHAO , Jinping LI , Guang LIU . Performance of MnO₂-0.39IrO_x composite oxides for water oxidation reaction in acidic media. Chinese Journal of Inorganic Chemistry, 2024, 40(6): 1135-1142. doi: 10.11862/CJIC.20230459
4. [4]
  Xinlong WANG , Zhenguo CHENG , Guo WANG , Xiaokuen ZHANG , Yong XIANG , Xinquan WANG . Enhancement of the fragile interface of high voltage LiCoO₂ by surface gradient permeation of trace amounts of Mg/F. Chinese Journal of Inorganic Chemistry, 2024, 40(3): 571-580. doi: 10.11862/CJIC.20230259
5. [5]
  Hongyi LI , Aimin WU , Liuyang ZHAO , Xinpeng LIU , Fengqin CHEN , Aikui LI , Hao HUANG . Effect of Y(PO₃)₃ double-coating modification on the electrochemical properties of Li[Ni_0.8Co_0.15Al_0.05]O₂. Chinese Journal of Inorganic Chemistry, 2024, 40(7): 1320-1328. doi: 10.11862/CJIC.20230480
6. [6]
  Xingyang LI , Tianju LIU , Yang GAO , Dandan ZHANG , Yong ZHOU , Meng PAN . A superior methanol-to-propylene catalyst: Construction via synergistic regulation of pore structure and acidic property of high-silica ZSM-5 zeolite. Chinese Journal of Inorganic Chemistry, 2024, 40(7): 1279-1289. doi: 10.11862/CJIC.20240026
7. [7]
  Dong-Xue Jiao , Hui-Li Zhang , Chao He , Si-Yu Chen , Ke Wang , Xiao-Han Zhang , Li Wei , Qi Wei . Layered (C5H6ON)2[Sb2O(C2O4)3] with a large birefringence derived from the uniform arrangement of π-conjugated units. Chinese Journal of Structural Chemistry, 2024, 43(6): 100304-100304. doi: 10.1016/j.cjsc.2024.100304
8. [8]
  Cheng PENG , Jianwei WEI , Yating CHEN , Nan HU , Hui ZENG . First principles investigation about interference effects of electronic and optical properties of inorganic and lead-free perovskite Cs₃Bi₂X₉ (X=Cl, Br, I). Chinese Journal of Inorganic Chemistry, 2024, 40(3): 555-560. doi: 10.11862/CJIC.20230282
9. [9]
  Liyang ZHANG , Dongdong YANG , Ning LI , Yuanyu YANG , Qi MA . Crystal structures, luminescent properties and Hirshfeld surface analyses of three cadmium(Ⅱ) complexes based on 2-(3-(pyridin-2-yl)-1H-pyrazol-1-yl)benzoate. Chinese Journal of Inorganic Chemistry, 2024, 40(10): 1943-1952. doi: 10.11862/CJIC.20240079
10. [10]
  Yangrui Xu , Yewei Ren , Xinlin Liu , Hongping Li , Ziyang Lu . 具有高传质和亲和表面的NH₂-UIO-66基疏水多孔液体用于增强CO₂光还原. Acta Physico-Chimica Sinica, 2024, 40(11): 2403032-. doi: 10.3866/PKU.WHXB202403032
11. [11]
  Ping Lu , Baoyin Du , Ke Liu , Ze Luo , Abiduweili Sikandaier , Lipeng Diao , Jin Sun , Luhua Jiang , Yukun Zhu . Heterostructured In2O3/In2S3 hollow fibers enable efficient visible-light driven photocatalytic hydrogen production and 5-hydroxymethylfurfural oxidation. Chinese Journal of Structural Chemistry, 2024, 43(8): 100361-100361. doi: 10.1016/j.cjsc.2024.100361
12. [12]
  Juan Guo , Mingyuan Fang , Qingsong Liu , Xiao Ren , Yongqiang Qiao , Mingju Chao , Erjun Liang , Qilong Gao . Zero thermal expansion in Cs₂W₃O₁₀. Chinese Chemical Letters, 2024, 35(7): 108957-. doi: 10.1016/j.cclet.2023.108957
13. [13]
  Renshu Huang , Jinli Chen , Xingfa Chen , Tianqi Yu , Huyi Yu , Kaien Li , Bin Li , Shibin Yin . Synergized oxygen vacancies with Mn2O3@CeO2 heterojunction as high current density catalysts for Li–O2 batteries. Chinese Journal of Structural Chemistry, 2023, 42(11): 100171-100171. doi: 10.1016/j.cjsc.2023.100171
14. [14]
  Hao BAI , Weizhi JI , Jinyan CHEN , Hongji LI , Mingji LI . Preparation of Cu₂O/Cu-vertical graphene microelectrode and detection of uric acid/electroencephalogram. Chinese Journal of Inorganic Chemistry, 2024, 40(7): 1309-1319. doi: 10.11862/CJIC.20240001
15. [15]
  Wenlong LI , Xinyu JIA , Jie LING , Mengdan MA , Anning ZHOU . Photothermal catalytic CO₂ hydrogenation over a Mg-doped In₂O_3-x catalyst. Chinese Journal of Inorganic Chemistry, 2024, 40(5): 919-929. doi: 10.11862/CJIC.20230421
16. [16]
  Haojie Duan , Hejingying Niu , Lina Gan , Xiaodi Duan , Shuo Shi , Li Li . Reinterpret the heterogeneous reaction of α-Fe₂O₃ and NO₂ with 2D-COS: The role of SDS, UV and SO₂. Chinese Chemical Letters, 2024, 35(6): 109038-. doi: 10.1016/j.cclet.2023.109038
17. [17]
  Yatian Deng , Dao Wang , Jinglan Cheng , Yunkun Zhao , Zongbao Li , Chunyan Zang , Jian Li , Lichao Jia . A new popular transition metal-based catalyst: SmMn₂O₅ mullite-type oxide. Chinese Chemical Letters, 2024, 35(8): 109141-. doi: 10.1016/j.cclet.2023.109141
18. [18]
  Haohao Sun , Wenxuan Wang , Yuli Xiong , Zelang Jian , Wen Chen . Boosting the electrochromic properties by large V₂O₅ nanobelts interlayer spacing tuned via PEDOT. Chinese Chemical Letters, 2024, 35(9): 109213-. doi: 10.1016/j.cclet.2023.109213
19. [19]
  Xinpeng LIU , Liuyang ZHAO , Hongyi LI , Yatu CHEN , Aimin WU , Aikui LI , Hao HUANG . Ga₂O₃ coated modification and electrochemical performance of Li_1.2Mn_0.54Ni_0.13Co_0.13O₂ cathode material. Chinese Journal of Inorganic Chemistry, 2024, 40(6): 1105-1113. doi: 10.11862/CJIC.20230488
20. [20]
  Xinting XIONG , Zhiqiang XIONG , Panlei XIAO , Xuliang NIE , Xiuying SONG , Xiuguang YI . Synthesis, crystal structures, Hirshfeld surface analysis, and antifungal activity of two complexes Na(Ⅰ)/Cd(Ⅱ) assembled by 5-bromo-2-hydroxybenzoic acid ligands. Chinese Journal of Inorganic Chemistry, 2024, 40(9): 1661-1670. doi: 10.11862/CJIC.20240145

Get Citation

PDF

XML

Metrics

PDF Downloads(1276)
Abstract views(2204)
HTML views(13)

通讯作者: 陈斌, bchen63@163.com

1.
沈阳化工大学材料科学与工程学院沈阳 110142

Dispersion and Acidity of Niobia on Nb2O5/γ-Al2O3

Metrics

通讯作者: 陈斌, bchen63@163.com

Dispersion and Acidity of Niobia on Nb₂O₅/γ-Al₂O₃