Near-unity emission in zero-dimensional Sb(III)-based halides intervened by hydrogen bonds towards efficient solid-state lighting technology

Zero-dimensional (0D) metal halides have garnered considerable interest owing to their superb optical characteristics , and adaptable architectures. Two 0D organic-inorganic metal halides (OIMHs) (C 20 H 20 P) 2 SbCl 5 ·(EA) ([C 20 H 20 P] + = ethyltriphenylphosphine) and (C 20 H 20 P) 2 SbCl 5 ·(IPA) were successfully synthesized and investigated using a simple solvent-evaporation approach. These OIMHs possess a similar structure, except for the solvent molecules in the lattice, however, their photoluminescence quantum yields (PLQYs) exhibit a considerable difference, with 99.82% in (C 20 H 20 P) 2 SbCl 5 ·(EA) and 73.7% in (C 20 H 20 P) 2 SbCl 5 ·(IPA). Bond-order and crystal orbital Hamilton population (COHP) calculations reveal that (C 20 H 20 P) 2 SbCl 5 ·EA system exhibits stronger hydrogen bonds , leading to stronger supramolecular interactions, which suppress non-radiative transition. The experimental results and density functional theory (DFT) calculations suggest an increase in PLQY, which could be attributed to the stronger hydrogen bonding in (C 20 H 20 P) 2 SbCl 5 ·(EA) resulting in strong interactions between the organic and inorganic components, good mobility, and improved exciton utilization. This study introduces a rational strategy for microstructure optimization, which builds upon solvent modulation to achieve stronger hydrogen bonding and thus improve the PLQY of 0D OIMHs.