Measuring internal quantum efficiency to demonstrate hot exciton dissociation

Abstract

Grancini et al. reported that “hot [charge transfer state] dissociation produces an overall increase in the charge generation yield” in organic solar cells (OSCs). If true, this is an important result as the process could dramatically improve efficiencies. Hot excitons are a 'hot' topic but was the increase in internal quantum efficiency (IQE) seen by Grancini et al. really due to hot excitons? In this Correspondence we demonstrate that when interference and other optical effects are correctly accounted for, the apparent strong contribution from hot excitons is absent...