通过使用尺寸选择的 ZnO 胶体系统地改变受主态密度来调节电子转移速率。

Tuning electron transfer rates via systematic shifts in the acceptor state density using size-selected ZnO colloids.

机构信息

Department of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, USA.

出版信息

J Am Chem Soc. 2010 Oct 13;132(40):13963-5. doi: 10.1021/ja104482t.

PMID:20858008

Abstract

We report direct measurements of the influence of the available density of acceptor states on the rate of near-barrierless electron transfer between a dye sensitizer and an oxide semiconductor. The electron donor was the excited state of a zinc porphyrin, and the acceptors were a series of size-selected ZnO nanocrystals. The available density of states was tuned by controlling the relative position of the ZnO band edge using quantum confinement. The resulting change in the rate was consistent with a simple model of the state density as a function of energy above the ZnO band edge.

摘要

我们报告了受主态密度对染料敏化剂和氧化物半导体之间近无势垒电子转移速率影响的直接测量结果。电子供体是锌卟啉的激发态，受体是一系列尺寸选择的 ZnO 纳米晶体。通过控制 ZnO 能带边缘的相对位置，利用量子限制来调节可用态密度。所得速率变化与一个简单的态密度随 ZnO 能带边缘上方能量变化的模型一致。