From the inside out : colloidal CdSe/CdS semiconductor nanorods : a study on the influence of their structures, surface ligands, and interactions with Redox-Active (Poly)Dopamine

The main focus of this thesis was the preparation of using nanorods (NRs) as photosensitizers, and divided into three chapters, where the structure of CdSe/CdS NRs, the phase transfer of CdSe/CdS dot-in-rod NRs and the interactions between dot-in-rod NRs and dopamine / polydopamine were discussed. Larger influence of surface defect was discovered in the inside-out NRs in the photoluminescence spectroscopy then further confirmed in the transient absorption spectroscopy. The phase transfer of the dot-in-rod NRs was successful monitored by FT-IR. And the influence of surface electron trap (ns scale) and hole trap (ps scale) was discovered in photoluminescence spectroscopy then further confirmed in time-resolved emission spectroscopy and transient absorption spectroscopy. The interaction between NRs and dopamine or polydopamine differed from surface ligands. With MUA ligand, the quenching mechanism was electron transfer which was further confirmed by transient absorption spectroscopy on the polydopamine coated MUA-NRs. With HS-PEG-OCH3 ligand, the quenching mechanism was more likely to be hole transfer.