Electrochemical preparation and characterization of surface-fluorinated TiO2 nanoporous film and its enhanced photoelectrochemical and photocatalytic properties

被引:124
作者
Cheng, X. F. [1 ]
Leng, W. H. [1 ]
Liu, D. P. [1 ]
Xu, Y. M. [1 ]
Zhang, J. Q. [1 ]
Cao, C. N. [1 ,2 ]
机构
[1] Zhejiang Univ, Dept Chem, Hangzhou 310027, Peoples R China
[2] Chinese Acad Sci, Inst Met Res, State Key Lab Corros & Protect Met, Shenyang 110016, Peoples R China
关键词
D O I
10.1021/jp7097476
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
In recent years, surface fluorination of TiO2 has been demonstrated to be an efficient method for improving its photocatalytic (PC) reactivity toward some pollutants. In this paper, a new and simple method for surface fluorination and porosity-creating of TiO2 is Presented. The sample was prepared by anodization of TiO2 in HF aqueous solutions formed by direct thermal oxidization of titanium sheet. The preparation conditions were optimized. The prepared samples were characterized by scanning electron microscopy (SEM), Raman spectroscopy, UV-vis diffuse reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL). The photoelectrochemical (PEC) and photocatalytic (PC) properties of the samples were also investigated. SEM and Raman showed that the anodization made the TiO2 nanoporous, which consequently increased markedly the specific surface area, but did not change the bulk crystal structure under a certain preparation condition. DRS analysis revealed that the light absorption was decreased after electrochemical etching. The band gap energy narrowed from 3.15 to 3.04 eV. The surface fluorination of the etched-TiO2 was evidently supported by XPS. Highly enhanced PEC performance and PC activities for the degradation of target pollutants, phenol, methylene blue, and reactive brilliant red on the etched-TiO2 were observed. The possible reasons for such an improvement were studied in detail by a combination of the abovementioned methods and (photo) electrochemical techniques. It is mainly attributed to the enhanced specific surface area, negative-shifted appearing energy band edges, decreased surface recombination centers, and/or favorable charge transfer rate. The F-containing TiO2 electrode has an excellent stability against fluoride desorption.
引用
收藏
页码:8725 / 8734
页数:10
相关论文
共 47 条
[1]   Photocatalytic activity of sol-gel-derived nanocrystalline titania [J].
Baiju, K. V. ;
Shukla, S. ;
Sandhya, K. S. ;
James, J. ;
Warrier, K. G. K. .
JOURNAL OF PHYSICAL CHEMISTRY C, 2007, 111 (21) :7612-7622
[2]   Doubling exponent models for the analysis of porous film electrodes by impedance.: Relaxation of TiO2 nanoporous in aqueous solution [J].
Bisquert, J ;
Garcia-Belmonte, G ;
Fabregat-Santiago, F ;
Ferriols, NS ;
Bogdanoff, P ;
Pereira, EC .
JOURNAL OF PHYSICAL CHEMISTRY B, 2000, 104 (10) :2287-2298
[3]   Enhanced photoelectrocatalytic performance of Zn-doped WO3 photocatalysts for nitrite ions degradation under visible light [J].
Cheng, X. F. ;
Leng, W. H. ;
Liu, D. P. ;
Zhang, J. Q. ;
Cao, C. N. .
CHEMOSPHERE, 2007, 68 (10) :1976-1984
[4]   MOTT-SCHOTTKY PLOTS AND FLAT-BAND POTENTIALS FOR SINGLE-CRYSTAL RUTILE ELECTRODES [J].
COOPER, G ;
TURNER, JA ;
NOZIK, AJ .
JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 1982, 129 (09) :1973-1977
[5]   LIGHT-INDUCED REDOX REACTIONS IN NANOCRYSTALLINE SYSTEMS [J].
HAGFELDT, A ;
GRATZEL, M .
CHEMICAL REVIEWS, 1995, 95 (01) :49-68
[6]   Photoreactivity of sol-gel TiO2 films formed on soda-lime glass substrates:: Effect of SiO2 underlayer containing fluorine [J].
Hattori, A ;
Shimoda, K ;
Tada, H ;
Ito, S .
LANGMUIR, 1999, 15 (16) :5422-5425
[7]   ENVIRONMENTAL APPLICATIONS OF SEMICONDUCTOR PHOTOCATALYSIS [J].
HOFFMANN, MR ;
MARTIN, ST ;
CHOI, WY ;
BAHNEMANN, DW .
CHEMICAL REVIEWS, 1995, 95 (01) :69-96
[8]   Effects of surface oxygen vacancies on photophysical and photochemical processes of Zn-doped TiO2 nanoparticles and their relationships [J].
Jing, Liqiang ;
Xin, Baifu ;
Yuan, Fulong ;
Xue, Lianpeng ;
Wang, Baiqi ;
Fu, Honggang .
JOURNAL OF PHYSICAL CHEMISTRY B, 2006, 110 (36) :17860-17865
[9]  
JOHN CF, 1999, J ELECTROCHEM SOC, V146, P1960
[10]   Electrochemical and photoelectrochemical investigation of single-crystal anatase [J].
Kavan, L ;
Gratzel, M ;
Gilbert, SE ;
Klemenz, C ;
Scheel, HJ .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1996, 118 (28) :6716-6723