Kevin E. Rivera Cruz and David F. Watson
Charge transfer across interfaces of semiconductor heterostructures is the key for efficient solar energy conversion. PbS quantum dots (QDs) interfaced with V2O5 nanowires (NWs) provide a promising system for harnessing solar energy efficiently by spatial separation of charge carriers through type II interface. The PbS/V2O5 heterostructures were succesfully prepared via linker-assisted assembly (LAA) and successive ionic layer adsorption and reaction (SILAR). For LAA, the cysteinate (Cys) capped PbS QDs were synthesized by ligand exchange with oleate capped PbS QDs. The Cys capped PbS QDs were characterized by Fourier transform infrared (FT-IR), Nuclear Magnetic Resonance (NMR) and Ultraviolet visible spectroscopy (UV-vis). Attachment of PbS QDs onto V2O5 NWs was confirmed by Transmission electron (TEM) and Scanning electron (SEM) microscopy and Energy-dispersive X-ray spectroscopy (EDS). Ongoing experiments are focused on spectroscopic characterization of excited-state charge-transfer processes within the heterostructures.