An Approach for Optimizing the Shell Thickness of Core−Shell Quantum Dots Using Photoinduced Charge Transfer

High Resolution Image Download MS PowerPoint Slide Photoinduced charge-transfer dynamics between CdSe quantum dots (QDs) possessing varying monolayers of ZnS and hole scavengers such as phenothiazine (PT) and N -methylphenothiazine (NMPT) were investigated for optimizing the shell thickness of core−shell quantum dots. Spectroscopic investigations indicate that phenothiazine binds onto the surface of bare CdSe QDs, resulting in the photoluminescence quenching, and two monolayers of ZnS prevent the electron-transfer process. Methodologies presented here can provide quantitative information on the optimum shell thickness of core−shell QDs, which can suppress the undesired electron transfer and provide maximum luminescence yield.