期刊：
Journal of Physical Chemistry C,2010年114(42):18198-18206 ISSN：1932-7447
通讯作者：
Zhang, Lizhi
作者机构：
[Zhang, Lizhi; Zhang, Xi] Cent China Normal Univ, Key Lab Pesticide & Chem Biol, Minist Educ, Coll Chem, Wuhan 430079, Peoples R China.
通讯机构：
[Zhang, Lizhi] C;Cent China Normal Univ, Key Lab Pesticide & Chem Biol, Minist Educ, Coll Chem, Wuhan 430079, Peoples R China.
摘要：
Foreign nonmetal or metal element doping has been widely used to tailor the electronic and band structures of wide band gap binary oxide semiconductor photocatalysts, extending their absorption edges into the visible light range for better utilization of solar light. Besides doping with foreign elements, self-doping can also tune the electronic and band structures of semiconductor photocatalysts but only limited to binary metal oxides, such as oxygen-deficient TiOx (x < 2). In this study, we demonstrate that self-doping is able to tune the electronic and band structures of ternary semiconductor photocatalysts and thus significantly enhance their photocatalytic activities by utilizing BiOI as the example. Density functional theory calculations revealed that iodine self-doping could effectively tune the electronic structures of BiOI. Motivated by the calculations, iodine self-doped bismuth oxyiodide photocatalysts were synthesized with a soft chemical method to illustrate this band structure tailoring approach. Experimental results confirmed that self-doping could change the electronic structures to intrinsically improve the optical absorption property and charge transfer ability, thus enhancing the photocatalytic activity of ternary semiconductors. Meanwhile, the intense absorption with a steep absorption edge of self-doped ternary semiconductors is different from that of foreign elements doped TiO2 with discrete bands, confirming this is a novel electronic and band structure tuning method. This successful band structure tailoring example of ternary semiconductors suggests the self-doping strategy could be general to develop novel visible light driven ternary photocatalysts with enhanced performances.
摘要：
Carbon-modified niobium oxide (Nb2O5) nanostructures, that firstly exhibited good visible light photocatalytic activity of Nb2O5 species, were synthesized by utilizing a low temperature, one-pot nonaqueous sol–gel approach. The resulting products were characterized by powder X-ray diffraction, scanning electron microscopy, transmission electron microscopy and nitrogen adsorption. Unlike the commercial or other reported Nb2O5 products that only respond to the UV-light irradiation, the present carbon-modified Nb2O5 nanostructures obtained at 200 °C in our experiment exhibited much better photocatalytic activity on degradation of RhB under visible light, which was about 39 times of that of commercial Nb2O5, 18 times of that of Degussa P25, and 5 times of that of carbon modified mesoporous TiO2. Moreover, these carbon-modified Nb2O5 nanostructures were also able to efficiently split water under visible light. The growth mechanism and the origin of visible light photocatalytic activity of the resulting Nb2O5 nanostructures were proposed. These carbon-modified Nb2O5 products are expected to be more suitable candidates than that of the most studied TiO2 as visible light photocatalysts.
作者：
Wanjun WANG;Lizhi ZHANG;Taicheng AN;Ho Yin YIP;Po Keung WONG
作者机构：
[Wanjun WANG; Ho Yin YIP; Po Keung WONG] Shcool of Life Sciences,The Chinese University of Hong Kong,Shatin,NT,Hong Kong SAR,CHINA;[Lizhi ZHANG] Key Laboratory of Pesticide & Chemical Biology of Ministry of Education,College of Chemistry,Huazhong Normal University,Wuhan,CHINA;[Taicheng AN] State Key Laboratory of Organic Geochemistry,Guangzhou Institute of Geochemistry,Chinese Academy of Sciences,Guangzhou 510640,CHINA
会议名称：
第十五届全国催化学术会议
会议时间：
2010-6-1
会议地点：
广州
会议主办单位：
中国化学会
会议论文集名称：
第十五届全国催化学术会议论文集
摘要：
The roles of photogenerated charged and reactive species including h+,e-,·O2-,H2O2,·Ohbulk or ·Ohsurface in visible-light-driven (VLD) photocatalytic degradation of pollutants and disinfection of bacteria is still a controversial issue.In this study,a selected VLD photocatalyst,B-Ni-codoped TiO2 (BNT) microsphere,was used to study their VLD photocatalytic activities for dye degradation and bacterial disinfection.The BNT microsphere was prepared by an aerosol-assisted flow synthesis method with a surface area of 90 m2/g and band gap energy of 2.25 eV1.Under visible light irradiation,the as-prepared BNT microspheres showed high photocatalytic degradation of the selected synthetic dye,Rhodamine B (RhB),and disinfection of the selected bacterium,Escherischia coli K-12.
期刊：
Journal of Physical Chemistry C,2010年114(26):11534-11541 ISSN：1932-7447
通讯作者：
Zhang, Lizhi
作者机构：
[Zhang, Lizhi; Xu, Hua] Cent China Normal Univ, Coll Chem, Minist Educ, Key Lab Pesticide & Chem Biol, Wuhan 430079, Peoples R China.
通讯机构：
[Zhang, Lizhi] C;Cent China Normal Univ, Coll Chem, Minist Educ, Key Lab Pesticide & Chem Biol, Wuhan 430079, Peoples R China.
摘要：
We demonstrate a low-temperature, one-pot nonaqueous sol−gel method for the selective synthesis of C−Cl-codoped TiO2 with different crystal phases and morphologies, including anatase nanocrystals, rutile nanorods, and a mixed phase with anatase and rutile nanocrystals. The synthetic protocol employed titanium tetrachloride as the titanium precursor and the mixture of chloroform and ethanol as the solvent. The as-prepared C−Cl-codoped TiO2 powders were characterized in detail by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, high-resolution TEM, X-ray photoelectron spectroscopy, and UV−vis diffuse reflectance spectroscopy. We evaluated their photocatalytic performances by the degradation of rhodamine B (RhB) solution under visible-light irradiation. On the basis of the above measurements, the doping process and dopant origin of C−Cl-codoped TiO2 as well as the formation mechanism of different phases were analyzed. We concluded that the tuning of the chloroform volume in the reaction system could easily control the final TiO2 phase and realize the controllable C−Cl codoping. The chlorine dopant in C−Cl-codoped TiO2 might originate from TiCl4, not from the decomposition of chloroform. We also analyzed the C−Cl-codoping modes and their influence on the visible-light photocatalytic activity of the final C−Cl-codoped TiO2. This study provides a facile, nonaqueous approach to synthesize tunable C−Cl-codoped TiO2 with enhanced visible-light-driven photocatalytic activity.
期刊：
Journal of Physical Chemistry C,2009年113(17):7200-7206 ISSN：1932-7447
通讯作者：
Jia, Falong
作者机构：
[Zhang, Lizhi; Jia, Falong] Cent China Normal Univ, Coll Chem, Wuhan 430079, Peoples R China.;[Wong, Ka-wai] Chinese Univ Hong Kong, Dept Phys, Shatin, Hong Kong, Peoples R China.
通讯机构：
[Jia, Falong] C;Cent China Normal Univ, Coll Chem, Wuhan 430079, Peoples R China.
摘要：
Uniform nanostructured palladium (Pd) has been successfully electrodeposited directly on gold substrate through a facile template-free approach, which involved a cyclic electrochemical deposition/dissolution of Pd. Under the regulation of potential scan and surfactant, standing Pd nanoplates and nanotrees were prepared. Improved and superior electrocatalytic activities toward the oxidation of ethanol were observed from these electrodes coated with nanostructured Pd. Furthermore, the uniform Pd nanostructures can be conveniently deposited onto a flexible substrate with a gold precoating, thus allowing fabrication of miniaturized flexible devices. This approach provides a simple route for the synthesis of highly catalytic Pd nanostructures with an excellent electrical contact to a substrate, which is important for the overall device performance. The critical effects exerted by the electrochemical conditions and surfactant will also be discussed.
期刊：
Journal of Physical Chemistry C,2009年113(38):16625-16630 ISSN：1932-7447
通讯作者：
Zhang, Lizhi
作者机构：
[Zhang, Lizhi; Xiao, Haiyan; Ai, Zhihui] Cent China Normal Univ, Coll Chem, Minist Educ, Key Lab Pesticide & Chem Biol, Wuhan 430079, Peoples R China.
通讯机构：
[Zhang, Lizhi] C;Cent China Normal Univ, Coll Chem, Minist Educ, Key Lab Pesticide & Chem Biol, Wuhan 430079, Peoples R China.
摘要：
Hierarchical CeO2 nanocrystal microspheres were synthesized with a nonaqueous sol−gel method at a low temperature of 120 °C. The products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), and nitrogen sorption measurements. The adsorption performances of hierarchical CeO2 nanocrystal microspheres were tested with the batch removals of typical pollutants of Cr(VI) and rhodamine B from simulated wastewater. It was found that the nanostructured CeO2 could effectively remove Cr(VI) without pH preadjustment. The Freundlich adsorption isotherm was applicable to describe the removal processes. Kinetics of the Cr(VI) removal was found to follow pseudosecond-order rate equation. Furthermore, the as-prepared and Cr(VI)-adsorbed hierarchical CeO2 nanocrystal microspheres were carefully analyzed by X-ray photoelectron spectroscopy (XPS). On the basis of the XPS results, a possible mechanism of Cr(VI) removal with hierarchical CeO2 nanocrystal microspheres was proposed. Moreover, these nonaqueous sol−gel synthesized hierarchical CeO2 nanocrystal microspheres also exhibited remarkable ability to remove rhodamine B, suggesting they are promising absorbents for wastewater treatment.
期刊：
Journal of Physical Chemistry C,2009年113(14):5455-5459 ISSN：1932-7447
通讯作者：
Zhang, Lizhi
作者机构：
[Zhang, Lizhi; Li, Pengna; Ding, Xing; Song, Xiao; Ai, Zhihui] Cent China Normal Univ, Coll Chem, Key Lab Pesticide & Chem Biol Minist Educ, Wuhan 430079, Peoples R China.
通讯机构：
[Zhang, Lizhi] C;Cent China Normal Univ, Coll Chem, Key Lab Pesticide & Chem Biol Minist Educ, Wuhan 430079, Peoples R China.
摘要：
We report that hollow spheres of transition metal oxides (TiO2, ZrO2, SnO2, Fe2O3, and Co3O4) could be formed in flowing aerosols. The formation of hollow structures was attributed to the in situ emission of gas phase HBO2 from the inner part of the metal oxide microspheres during the pyrolysis of flowing aerosols. We interestingly found that the addition of H3BO3 could not only result in the formation of hollow spheres but also tailor the property of the metal oxides. The resulting TiO2 and Co3O4 hollow spheres exhibited enhanced photocatalytic and magnetic properties compared to the counterpart solid spheres, respectively. We believe this study provides a simple and convenient method for industrial production of transition metal oxide hollow spheres with enhanced properties.
