Hydrophobic Chain-Induced Conversion of Three-Dimensional Perovskite Nanocrystals to Gold Nanocluster-Grafted Two-Dimensional Platelets for Photoinduced Electron Transfer Substrate Formulation.

Abstract

Considering the augmentation of new generation energy harvesting devices and applications of electron-hole separation therein, conversion of 3D cubic CsPbBr3 perovskite nanocrystals into 2D-platelets through ligand-ligand hydrophobic interactions has been conceived here. Cationic surfactants with various chain length coated the gold nanoclusters (AuNCs) that interact with oleic acid (OA) and oleylamine (OAm) coated 3D CsPbBr3 nanocrystals to disintegrate the crystallinity of the perovskites and reformation of AuNC-grafted 2D-platelets of unusually large size. The planar perovskite-derivatives act as an exciton donor to the embedded AuNCs through photoinduced electron transfer (PET). This process is controlled by the optimum surfactant chain length. Transient absorption spectroscopy shows that the fastest radical growth time (4 ps) was with the 14-carbon containing tail of the surfactant, followed by the 16-carbon (45 ps) and the 12-carbon (290 ps) ones. PET is administered by the energy gaps of the participating candidates that control the transition dynamics. Our findings can be a potential tool to develop metal nanocluster-based hybrid 2D perovskite-derived platelets for optoelectronic applications.