Heteroanionic Lead‐Free Double‐Perovskite Halides for Bandgap Engineering

The hetero-anionic lead-free double perovskite halides are realized through mechanochemical synthesis by Tae Heon Kim and co-workers in article number 2201119. The degree of anion substitution is tunable inducing manipulation of the band gaps and the emitted colors of the anionic-mixed double perovskite halides. The band gap engineering via anion exchange is applicable to fabricate lead-free optoelectronic devices with high performance.