不同晶型Bi_2O_3可见光光催化降解罗丹明B的研究  

Visible-Light Photocatalytic Degradation of RhB by Bi_2O_3 Polymorphs

作　　者：邹文[1] 郝维昌[1] 信心[1] 王天民[1] 

机构地区：[1]北京航空航天大学材料物理与化学研究中心,北京100191

出　　处：《无机化学学报》2009年第11期1971-1976,共6页Chinese Journal of Inorganic Chemistry

基　　金：国家自然科学基金资助项目(No.50732004)

摘　　要：采用化学沉淀法制备了α、β、γ3种晶体结构的Bi2O3光催化剂。利用XRD、TEM、氮气吸附、TG-DSC、紫外-可见漫反射光谱对样品的晶体结构、微观形貌、光学吸收特性进行了表征,并以罗丹明B（RhB）作为模型污染物,研究了不同的粉体光催化剂在可见光（λ〉420 nm）照射下的光催化能力。结果表明：制备的α-Bi2O3为长3μm、宽1μm的板条状颗粒,带隙为2.84 eV;β-Bi2O3为粒径约150 nm的不规则颗粒,带隙为2.75 eV;γ-Bi2O3为直径6 nm、长度150～200 nm的纳米管,带隙为2.68 eV。在可见光照射下Bi2O3光催化降解RhB的活性如下：γ-Bi2O3〉β-Bi2O3〉α-Bi2O3,其中γ-Bi2O3在辐照60 min后对罗丹明B的脱色率可达97%以上。The α, β, and γ-Bi2O3 were obtained by a chemical precipitation method. The crystal structures, morphologies and optical properties of Bi2O3 polymorphs were characterized by X-ray diffraction （XRD）, transmission electron microscopy （TEM）, nitrogen adsorption method, thermal gravimetry-differential scanning calorimetry （TG- DSC） and ultraviolet-visible diffuse reflectance spectroscopy （UV-Vis DRS）. The photoeatalytie performance of Bi2O3 was evaluated using rhodamine B （RhB） as a model pollutant under visible light illumination （λ〉420 nm）. The result showed that the lath-shaped α-Bi2O3 with a band gap of 2.84 eV was 3 μm in length and 1 μm in width; the irregular β-Bi2O3 with a band gap of 2.75 eV had a particle size of approximately 150 nm; the nanotube γ-Bi2O3 with a band gap of 2.68 eV was 6 nm in diameter and 150 nm to 200 nm in length. The photocatalytic degradation of RhB by Bi2O3 polymorphs under visible light illumination were as follows： γ-Bi2O3〉β-Bi2O3〉α-Bi2O3. The γ-Bi2O3 nanotube exhibited the best photocatalytic performance which can effectively degrade 97% RhB within 60 min.

关 键 词：BI2O3 可见光 光催化 纳米管 

分 类 号：O643[理学—物理化学]