Multiple Exciton Generation in Colloidal Nanocrystals

Nanomaterials

Charles Smith¹ 

[1] School of Physics and Astronomy and Photon Science Institute, University of Manchester, Manchester M13 9PL, UK; E-Mail

关键词: multiple exciton generation;    carrier multiplication;    nanocrystals;    quantum dots;    nanoparticles;    solar cells;    photovoltaic;   

DOI  :  10.3390/nano4010019

来源: mdpi

【 摘 要 】

In a conventional solar cell, the energy of an absorbed photon in excess of the band gap is rapidly lost as heat, and this is one of the main reasons that the theoretical efficiency is limited to ~33%. However, an alternative process, multiple exciton generation (MEG), can occur in colloidal quantum dots. Here, some or all of the excess energy is instead used to promote one or more additional electrons to the conduction band, potentially increasing the photocurrent of a solar cell and thereby its output efficiency. This review will describe the development of this field over the decade since the first experimental demonstration of multiple exciton generation, including the controversies over experimental artefacts, comparison with similar effects in bulk materials, and the underlying mechanisms. We will also describe the current state-of-the-art and outline promising directions for further development.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.