| 异质型BiOI/NaBiO3光催化剂的合成及其光催化性能 |
| Synthesis of Heterojunction Type BiOI/NaBiO3 Photocatalyst and Enhanced Photocatalytic Activities |
| 作者 | 单位 | E-mail | | 姬磊 | 东北石油大学化学化工学院, 石油与天然气化工省高校重点实验室, 大庆 163318 | ljidqpi@163.com | | 王浩人 | 东北石油大学化学化工学院, 石油与天然气化工省高校重点实验室, 大庆 163318 | | | 于瑞敏 | 东北石油大学化学化工学院, 石油与天然气化工省高校重点实验室, 大庆 163318 | | | 姜震 | 东北石油大学化学化工学院, 石油与天然气化工省高校重点实验室, 大庆 163318 | | | 汪怀远 | 东北石油大学化学化工学院, 石油与天然气化工省高校重点实验室, 大庆 163318 | |
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| 摘要: 根据表面化学蚀刻原理采用加热冷凝回流的方法制备了一系列组成的异质结构BiOI/NaBiO3光催化剂。利用X射线粉末衍射(XRD)、扫描电子显微镜(SEM)和紫外-可见漫反射光谱(UV-Vis-DRS)等技术对其晶相结构、微观形貌和光吸收性能进行了表征。光催化实验表明, BiOI/NaBiO3在可见光下可以有效降解罗丹明B(RhB), 当BiOI与NaBiO3的物质的量分数为一定值时, 异质结构的光催化剂明显优于单一组分的光催化活性。通过加入不同的牺牲剂及荧光实验结果推测了该异质结构材料的光催化机理, 并且分析了其光生载流子的传输方向及光催化过程的活性物种。研究表明, BiOI/NaBiO3的催化活性增强主要归结为两者之间形成了有效的异质结构, 其内建电场能够促进光生载流子的分离, 同时光生空穴h+在光催化降解过程中是主要的活性物种。 |
| 关键词: 光催化 BiOI NaBiO3 异质结 机理 |
| 基金项目: 黑龙江省普通高等学校青年学术骨干支持计划(No.1251G002)、东北石油大学青年科学基金(No.2012QN114)和黑龙江省普通高校石油与 天然气化工重点实验室开放基金(No.HXHG2012-0)资助项目。 |
| Abstract: BiOI/NaBiO3 heterostructure photocatalysts were synthesized using HI as etching agents to react with NaBiO3 by a heating condensate reflux method according to surface chemical etching principle. Several characterization tools including X-ray powder diffraction (XRD), scanning electron microscope (SEM) and UV-Vis diffuse reflectance spectra (UV-Vis DRS) were employed to study the phase structures, morphologies and optical properties of the as-prepared samples respectively. From the degradation of Rhodamine B(RhB) under visible light irradiation experimental results, we can obtained that the absorption capacity of as-prepared samples were enhanced with increasing the BiOI amounts in the BiOI/NaBiO3 heterostructures until the BiOI/NaBiO3 ratio is 79.62%. With increasing BiOI content, the photocatalytic activity enhanced gradually and then decreased. As the BiOI content increase to 17.34%, the highest photocatalytic activity could be achieved, and the RhB almost faded completely with the time increasing to 100 min. The results show that the adsorption ability is only a factor not all to promote the photocatalytic ability. The EVB of NaBiO3 and BiOI were calculated to be 2.23 and 2.41 eV and the ECB of NaBiO3 and BiOI were -0.23 and 0.46 eV by the UV-Vis DRS method respectively. To evaluate the roles of reactive species during photocatalysis, different scavengers including benzoquinone, isopropyl alcohol and methanol were adopted as the traps for O2-, OH and h+ for RhB degradation. The results suggesting that h+ played major role for RhB degradation. Terephthalic acid photoluminescence (TA-PL) probing test demonstrated that OH could be negligible also. According to the band gap structure of BiOI/NaBiO3, the effects of scavengers and the PL experimental results, a possible charge separation processes between BiOI and NaBiO3, and the pathway for the photocatalytic activity enhancement mechanism was proposed. The heterojunction at the interface between p-BiOI and n-NaBiO3 can efficiently reduce the recombination of photogenerated electron-hole pairs and which accounts for the enhancement of photocatalytic activity. Form the analysis of potential, it is theoretically reasonable that the photocatalytic degradation of RhB could be attributed to the reaction of hole directly rather than OH and O2- radicals. |
| Keywords: photocatalysis BiOI NaBiO3 heterojunction mechanism |
| 投稿时间：2014-09-30 修订日期：2014-11-24 |
| 摘要点击次数: 2256 |
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| 姬磊,王浩人,于瑞敏,姜震,汪怀远.异质型BiOI/NaBiO3光催化剂的合成及其光催化性能[J].无机化学学报,2015,31(3):521-528. |
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