硼掺杂SiC的制备、表征及其可见光分解水产氢性能

采用原位碳热还原法制备了硼掺杂的β-SiC（β-SiC）光催化剂，并考察了其可见光下光催化分解水制氢的性能．利用X射线衍射仪、X射线光电子能谱、扫描电镜及紫外一可见吸收光谱等测试方法对所制备催化剂的晶型、形貌、表面性质及能带结构进行了表征．分析结果表明，硼原子掺杂进入SiC晶格并取代了Si位点，在价带上方形成了浅受主能级，从而导致了带隙宽变窄．浅受主能级作为空穴的捕获中心可抑制光生电子和空穴的复合．因此，与SiC相比，硼掺杂SiC光催化剂在可见光下催化分解水产氢的活性大大提高．当B／Si的摩尔比为0．05时，硼掺杂SiC表现出最高的光催化产氢活性．...

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Bibliographic Details
Published in物理化学学报 Vol. 30; no. 1; pp. 135 - 140
Main Author 董莉莉 王英勇 童希立 靳国强 郭向云
Format Journal Article
LanguageChinese
Published 中国科学院山西煤炭化学研究所，煤转化国家重点实验室，太原030001 2014
中国科学院大学，北京100049%中国科学院山西煤炭化学研究所，煤转化国家重点实验室，太原030001
Subjects
β-SiC
产氢
光催化
可见光
硼掺杂
B doping
产氢
硼掺杂
Photocatalysis
Hydrogen evolution
光催化
Visible light
β-SiC
可见光
Online AccessGet full text
ISSN1000-6818
DOI10.3866/PKU.WHXB201311052

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Summary:采用原位碳热还原法制备了硼掺杂的β-SiC（β-SiC）光催化剂，并考察了其可见光下光催化分解水制氢的性能．利用X射线衍射仪、X射线光电子能谱、扫描电镜及紫外一可见吸收光谱等测试方法对所制备催化剂的晶型、形貌、表面性质及能带结构进行了表征．分析结果表明，硼原子掺杂进入SiC晶格并取代了Si位点，在价带上方形成了浅受主能级，从而导致了带隙宽变窄．浅受主能级作为空穴的捕获中心可抑制光生电子和空穴的复合．因此，与SiC相比，硼掺杂SiC光催化剂在可见光下催化分解水产氢的活性大大提高．当B／Si的摩尔比为0．05时，硼掺杂SiC表现出最高的光催化产氢活性．
Bibliography:β-SIC; B doping; Photocatalysis; Hydrogen evolution; Visiblelight
11-1892/06
Boron-doped E-SiC （BxSiC） photocatalysts were prepared by in-situ carbothermal reduction, and their photocatalytic performances for H2 evolution under visible light irradiation were investigated. The crystal structure, surface property, morphology, and band gap structure of the BxSiC photocatalysts were studied using X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and ultraviolet-visible absorption spectroscopy. The characterization results indicate that B atoms have doped into the SiC lattice and substituted Si sites, leading to the formation of a shallow acceptor level above the valence band of SiC, resulting in a narrowed band gap energy. The shallow acceptor level acts as a hole trap, preventing the recombination of photo-excited electrons and holes. Therefore, the photocatalytic H2 evolution activity of B-doped SiC was greatly improved compared with that of SiC. The highest hydrogen evolution rat
ISSN:1000-6818
DOI:10.3866/PKU.WHXB201311052