极化电荷设计调控金属/半导体复合体系的能带结构
详细信息 查看官网全文
- 英文论文题名：Energy Band Engineering of Metal/Semiconductor Hybrid by Polarization Charge Design
- 论文作者：刘研 ; 江俊
- 英文论文作者：Yan Liu ; J.Jiang ; Department of Chemical Physics ; University of Science and Technology of China
- 年：2016
- 作者机构：中国科学技术大学化学物理系;
- 论文关键词：Ⅱ型异质结 ; Ⅰ型异质结 ; 极化电荷 ; 能带结构
- 会议召开时间：2016-07-01
- 会议录名称：中国化学会第30届学术年会摘要集-第四十分会：纳米体系理论与模拟
- 语种：中文
- 分类号：O649;TB33
- 学会代码：ZGHY
- 会议名称：中国化学会第30届学术年会-第四十分会 ; 纳米体系理论与模拟
- 会议地点：中国辽宁大连
- 主办单位：中国化学会
- 学会名称：中国化学会
- 页数：1
- 文件大小：161k
- 原文格式：D
- 会议级别：全国
摘要
在半导体体系中,设计异质结构(能带间隙呈现Ⅰ型嵌套对准和Ⅱ型交错对准)来调控电荷流动具有重要的应用价值。我们基于第一性原理模拟,提出利用复合材料表界面功函数的差异,诱导极化电荷的形成,实现调控能带结构。如下图所示的金属M负载在纳米半导体异质结S1-S2(Ⅰ型带隙匹配)上的体系,金属与半导体S2接触,由于功函数的差异产生极化电荷,极化电荷在半导体S2中的累积将有效抬升能带,从而与半导体S1形成Ⅱ型异质结构。光辐射条件下,光生电子-空穴会因为能带交错实现分离。通过密度泛函理论计算来筛选材料,指导实验制备得到了ZnS-(CdS/Au)纳米棒,验证了电子-空穴的分离,并有效提升了能量转化效率。该工作为纳米半导体复合材料在光电转化和光催化方面的应用提供了一个新的思路。
A first-principles study is performed to propose anddemonstrate a novel stragey toward convenient energy band engineering inmetal/semiconductor hybrids. In this design, a metallic nanoparticle(M) is interfaced with a type-Ⅰ bi nary heteronanostructure(S-S2). The calculatedresults indicate that the conversion from the straddling gap(type Ⅰ) of S1-S2 heterojunction to the staggered gap(type Ⅱ) of S1-(S2/M) ensures well-steeredcollections of electrons at th e surface of the exposed nanorod stem and holesat the metal surface of the node sheath.In the ternary architecture of S1-(S2/M),the work function difference would drivefree electrons to flow from M to S2 so as to level up the energy bands of S2, andeventually achieve the type-Ⅰ-to-type-Ⅱ conversion.
A first-principles study is performed to propose anddemonstrate a novel stragey toward convenient energy band engineering inmetal/semiconductor hybrids. In this design, a metallic nanoparticle(M) is interfaced with a type-Ⅰ bi nary heteronanostructure(S-S2). The calculatedresults indicate that the conversion from the straddling gap(type Ⅰ) of S1-S2 heterojunction to the staggered gap(type Ⅱ) of S1-(S2/M) ensures well-steeredcollections of electrons at th e surface of the exposed nanorod stem and holesat the metal surface of the node sheath.In the ternary architecture of S1-(S2/M),the work function difference would drivefree electrons to flow from M to S2 so as to level up the energy bands of S2, andeventually achieve the type-Ⅰ-to-type-Ⅱ conversion.
引文
[1]Zhuang,T.;Liu,Y.;Sun,M.;Jiang,J.;Yu,S.Angew.Chem.Int.Ed.2015,54:11495.
[2]Zhuang,T.;Liu,Y.;Li,Y.;Zhao,Y.;Jiang,J.;Yu,S.Angew.Chem.Int.Ed.2016,DOI:10.1002/anie.201601865
[3]Zhuang,T.;Liu,Y.;Li,Y.;Sun,M.;Jiang,J.;Yu,S.Under Revision
[2]Zhuang,T.;Liu,Y.;Li,Y.;Zhao,Y.;Jiang,J.;Yu,S.Angew.Chem.Int.Ed.2016,DOI:10.1002/anie.201601865
[3]Zhuang,T.;Liu,Y.;Li,Y.;Sun,M.;Jiang,J.;Yu,S.Under Revision