Zhang et al. report non-destructive halide exchange by employing butylammonium halide incorporated post-treatment to achieve perovskite with low trap density and tuneable bandgap for blue LEDs, with external quantum efficiencies of 23.6%, 20.9%, and 15.5% for emission peaks at 488, 478, and 468 nm, respectively.
- Kai Zhang
- Yang Shen
- Jian-Xin Tang
