Enhanced Multiple Exciton Generation in Quasi-One-Dimensional Semiconductors

被引：128

作者：

Cunningham, Paul D. ^{[1
]}

Boercker, Janice E. ^{[1
]}

Foos, Edward E. ^{[1
]}

Lumb, Matthew P. ^{[1
,2
]}

Smith, Anthony R. ^{[1
]}

Tischler, Joseph G. ^{[1
]}

Melinger, Joseph S. ^{[1
]}

机构：

[1] USN, Res Lab, Washington, DC 20375 USA

[2] George Washington Univ, Sch Engn & Appl Sci, Washington, DC 20052 USA

来源：

NANO LETTERS | 2011年 / 11卷 / 08期

关键词：

Multiple exciton generation; carrier multiplication; nanorods; nanocrystals; photovoltaic; EFFICIENCY CARRIER MULTIPLICATION; QUANTUM DOTS; CONVERSION EFFICIENCY; COLLOIDAL PBSE; SOLAR-CELLS; ABSORPTION; LIMITS;

D O I：

10.1021/nl202014a

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

The creation of a single electron-hole pair (i.e., exciton) per incident photon is a fundamental limitation for current optoelectronic devices including photodetectors and photovoltaic cells. The prospect of multiple exciton generation per incident photon is of great interest to fundamental science and the improvement of solar cell technology. Multiple exciton generation is known to occur in semiconductor nanostructures with increased efficiency and reduced threshold energy compared to their bulk counterparts. Here we report a significant enhancement of multiple exciton generation in PbSe quasi-one-dimensional semiconductors (nanorods) over zero-dimensional nanostructures (nanocrystals), characterized by a 2-fold increase in efficiency and reduction of the threshold energy to (2.23 +/- 0.03)E-g, which approaches the theoretical limit of 2E(g). Photovoltaic cells based on PbSe nanorods are capable of improved power conversion efficiencies, in particular when operated in conjunction with solar concentrators.

引用

页码：3476 / 3481

页数：6

共 47 条

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