| 黄应平.石墨烯-溴氧化铋复合物的制备及可见光光催化性能研究[J].分子催化,2014,(4):367-375 |
| 石墨烯-溴氧化铋复合物的制备及可见光光催化性能研究 |
| Preparation of Graphene –BiOBr composite and the enhanced photocatalytic activity under visible-light irradiation |
| 投稿时间：2014-03-31 修订日期：2014-07-05 |
| DOI： |
| 中文关键词: 石墨烯-溴氧化铋 负载 可见光 |
| 英文关键词:Gre-BiOBr composite recombination photocatalysis |
| 基金项目:国家自然科学基金(21377067，21207079，21177072)；湖北省新世纪人才入选人员优先资助项目(201203)；中国科学院生态环境研究中心开放基金(KF2011-07) |
|
| 摘要点击次数: 2061 |
| 全文下载次数: 4214 |
| 中文摘要: |
| 采用超声-水热法在溴氧化铋(BiOBr)上负载不同含量氧化石墨来制备石墨烯-溴氧化铋(Gre-BiOBr)复合物，利用X-射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、紫外可见漫反射(UV-Vis DRS)、荧光分光光度计(PL)、比表面积仪(BET)及红外光谱仪(FT-IR)对不同负载量的Gre-BiOBr进行初步表征。发现BiOBr负载石墨烯前后均为斜四方晶型(JCPDS:78-0348)，均为大小500-1000 nm片层状。在可见光照射下(λ≥420 nm)，以罗丹明B(Rhodamine B, RhB)和水杨酸(Salicylicacid, SA)作为降解底物，发现经过负载石墨烯后BiOBr的可见光活性有明显提高，且当负载质量比为10%时，Gre-BiOBr复合物表现出最好的可见光活性，此时光降解RhB反应速率(k10%Gre-BiOBr=0.046 min-1)约为单纯BiOBr(kBiOBr =0.02 min-1)的两倍。经测定10% Gre-BiOBr复合物的比表面积为10.50 m2/g，禁带宽度为2.61 eV，能吸收λ≥475 nm可见光。结合自由基捕获实验，发现该催化体系主要涉及超氧自由基(O2•−)和空穴(h+)的共同氧化作用。10% Gre-BiOBr催化剂循环使用5次，仍保持着良好光催化活性，表明该催化剂稳定性较好。 |
| 英文摘要: |
| Graphene-bismuth oxybromide (Gre-BiOBr) composites with different amounts of graphene loading on BiOBr were prepared by ultrasound-hydrothermal method, named BiOBr, 2% Gre-BiOBr, 6% Gre-BiOBr, 10% Gre-BiOBr and 14% Gre-BiOBr, respectively. The materials were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM), ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS), fluorotrophotometer(PL) and Brunauer-Emmett- Teller (BET). The results showed that the as-prepared catalysts were the diagonal square crystal shape(JCPDS card no: 78-0348), and the sheet of them were about 500-1000 nm sheets. Compared with pure BiOBr, the photocatalytic activity of Gre-BiOBr was significantly improved on the degradation of Rhodamine B (RhB) and Salicylicacid(SA) under visible light irradiation(λ≥420 nm). The 10% Gre-BiOBr catalyst showed the best photocatalytic activity and the degradation rate of RhB (k10%Gre-BiOBr=0.046 min-1) was twice than that of pure BiOBr (kBiOBr=0.020 min-1). The specific surface area and the band gap (Eg) of 10% Gre-BiOBr catalyst were 10.50 m2•g-1 and 2.61 eV (~475 nm). Based on the free radicals captured experiments, the catalytic mechanism was mainly related to the common oxidation of the super oxygen radical (O2•−) and holes (h+). The photocatalytic activity of 10% Gre-BiOBr was excellent in the recycle-usage for five times，so it had good stability. |
| HTML 查看全文 查看/发表评论 下载PDF阅读器 |
