Broadband red emission from one-dimensional hexamethonium lead bromide perovskitoid.

Broadband emissions from low-dimensional hybrid perovskites have aroused intense interest. However, the achievement of broadband red emission in lead halide perovskites remains challenging. Herein, we report a one-dimensional (1D) hybrid lead bromide perovskitoid, (HM)PbBr (HM = hexamethonium), featuring a corrugated "3 × 3" [PbBr] chain. The unique structure results in intriguingly red emission peaking at 692 nm, with a PLQY of around 6.24%. Our spectroscopic and computational studies reveal that the red emission derives from self-localized Pb, Pb and Br species confined within the inorganic lead bromide lattice that function as radiative centres. This finding will benefit the design of perovskite systems for efficient red emission.