Energy Funneling from Water-Dispersed Perovskites to Chromophores
Pooja Aggarwal, Anubhab Halder, Neelakshi Neelakshi, Ramesh Ramapanicker, Vishal Govind Rao
Abstract
Cesium lead halide perovskite nanocrystals (PNCs) have enjoyed enormous attention in optoelectronics and photovoltaics. However, instability under polar conditions and limited energy/charge transport due to long-chain capping ligands restrict their large-scale applications. We have engineered a short-chain multidentate bolaamphiphilic ligand (NKE-3), which provides synergistic passivation of the perovskite surface by one multidentate ionic terminal and localizes water molecules by another multidentate ionic terminal, leading to a water-suspended colloidal solution of PNCs. NKE-3 allows efficient long-range dipole-based fluorescence resonance energy transfer (FRET) from perovskites to Rhodamine B isothiocyanate (RITC) in water, with FRET efficiencies ranging from 96% to 98%. We calculated the FRET rate using the acceptor’s rise-time component, as it ensures no contamination from FRET-inactive donors. Moreover, we tuned the emission maxima of PNCs through halide exchange to optimize FRET efficiency. Such energy funneling to a suitable molecular photocatalyst is imperative for PNCs’ potential applications.