高等学校化学学报
高等學校化學學報
고등학교화학학보
CHEMICAL JOURNAL OF CHINESE UNIVERSITIES
2014年
12期
2624-2631
,共8页
王艳%张小超%赵丽军%赵晓霞%史宝萍%樊彩梅
王豔%張小超%趙麗軍%趙曉霞%史寶萍%樊綵梅
왕염%장소초%조려군%조효하%사보평%번채매
非金属掺杂%BiOCl%第一性原理%电子结构%光吸收性质%光催化
非金屬摻雜%BiOCl%第一性原理%電子結構%光吸收性質%光催化
비금속참잡%BiOCl%제일성원리%전자결구%광흡수성질%광최화
Non-metal doping%BiOCl%First-principle%Electronic structure%Optical absorption property%Photocatalysis
基于密度泛函理论的第一性原理分别研究了不同浓度Br和I掺杂BiOCl体系的能带结构、态密度、形成能和光学性质。研究结果表明,由于Br的4p和I的5p轨道作用, Br和I掺杂可在一定程度上降低BiOCl的禁带宽度,拓宽BiOCl的光吸收范围。 Br和I掺杂BiOCl的形成能计算结果表明, Br掺杂BiOCl的稳定性高于I掺杂体系。对于B, C, N, Si, P和S掺杂BiOCl体系,掺杂能级的形成主要由掺杂元素的np轨道贡献,使BiOCl吸收带边红移至可见光区。而S掺杂则位于价带顶位置,有效地降低了BiOCl禁带宽度,使BiOCl响应波长出现红移,且未形成中间能级,不易成为俘获陷阱,因此S掺杂将是一种提高BiOCl可见光光催化活性的改性方法。
基于密度汎函理論的第一性原理分彆研究瞭不同濃度Br和I摻雜BiOCl體繫的能帶結構、態密度、形成能和光學性質。研究結果錶明,由于Br的4p和I的5p軌道作用, Br和I摻雜可在一定程度上降低BiOCl的禁帶寬度,拓寬BiOCl的光吸收範圍。 Br和I摻雜BiOCl的形成能計算結果錶明, Br摻雜BiOCl的穩定性高于I摻雜體繫。對于B, C, N, Si, P和S摻雜BiOCl體繫,摻雜能級的形成主要由摻雜元素的np軌道貢獻,使BiOCl吸收帶邊紅移至可見光區。而S摻雜則位于價帶頂位置,有效地降低瞭BiOCl禁帶寬度,使BiOCl響應波長齣現紅移,且未形成中間能級,不易成為俘穫陷阱,因此S摻雜將是一種提高BiOCl可見光光催化活性的改性方法。
기우밀도범함이론적제일성원리분별연구료불동농도Br화I참잡BiOCl체계적능대결구、태밀도、형성능화광학성질。연구결과표명,유우Br적4p화I적5p궤도작용, Br화I참잡가재일정정도상강저BiOCl적금대관도,탁관BiOCl적광흡수범위。 Br화I참잡BiOCl적형성능계산결과표명, Br참잡BiOCl적은정성고우I참잡체계。대우B, C, N, Si, P화S참잡BiOCl체계,참잡능급적형성주요유참잡원소적np궤도공헌,사BiOCl흡수대변홍이지가견광구。이S참잡칙위우개대정위치,유효지강저료BiOCl금대관도,사BiOCl향응파장출현홍이,차미형성중간능급,불역성위부획함정,인차S참잡장시일충제고BiOCl가견광광최화활성적개성방법。
The band structures, density of states, formation energies and optical properties of different con-centration Br and I doped BiOCl systems were investigated via first principles based on the density functional theory. The results show that the incorporation of Br 4p and I 5p orbitals can reduce the energy gap of BiOCl, and then broaden the photo-absorption range. The calculated formation energy indicates that Br-doped BiOCl system has higher stability than I-doped BiOCl at the same doping concentration. For B, C, N, Si, P, S doped BiOCl systems, the impurity energy levels are mainly contributed to the np states of doping elements, which can make the red-shift of photo-absorption band edge into visible light region. Especially, the impurity levels of S-doped BiOCl system located in the top of valence band are difficult to become recombination center of photon-generated carriers, which can result in the reduction of BiOCl band-gap and the red-shift of light-responding scope. The S-doped BiOCl system will be a preferable modification method to improve the photo-catalytic activity of BiOCl.
