Electron transfer tuned by pressure-dependent aggregation-induced emission in InP/ZnS quantum dot–anthraquinone complexes

Abstract

Electron transfer (ET) process is considered a substantial factor in influencing the photoelectric conversion efficiency of optoelectronic devices. While pressure has demonstrated effective tune ET, a comprehensive investigation into the mechanisms for both restraining and promoting ET remains elusive. Herein, we have performed measurements using in situ high-pressure steady-state photoluminescence (PL), Raman scattering spectra, and femtosecond transient absorption (fs-TA) spectroscopy on InP/ZnS quantum dot–anthraquinone (InP/ZnS QD-AQ) complexes. The experimental results have demonstrated that the pressure-suppressed ET process in the InP/ZnS QD-AQ complexes arises from both the aggregation-induced emission (AIE) effect of AQ in toluene and the quantum confinement effect of the InP/ZnS QDs. The reduction in the distance between InP/ZnS QD and AQ under pressure emerges as a key factor that promotes the ET process in the InP/ZnS QD-AQ complexes. Furthermore, we observed that the pressure not only enhances the ET process but also suppresses the auger recombination process in liquid phase I of toluene, consequently leading to an enhancement in the photoelectric conversion efficiency. This study contributes to understanding the mechanism of the ultrafast dynamic processes in the pressure-induced QD-receptor complexes, and it has great potential for preparing efficient and stable optoelectronic devices.