Metal halide perovskites: promising materials toward next-generation circularly polarized luminescence

Metal halide perovskites (MHPs) have emerged as highly appealing materials for circularly polarized luminescence (CPL) related applications, owing to their spin-related photoelectric properties and flexible structural adjustment. However, the realization of high circular dichroic (CD) intensity and luminescence dissymmetry factors (g(lum)) remains a challenge faced in the field of CPL material research, which greatly impedes the commercial application of perovskite-based CPL. In this perspective, we discuss the fabrication strategies of intercalating chiral organic ammonium into MHPs and chiral regulation of MHPs without chiral organic ammonium ligands, resulting in CPL emission. We then summarize the progress in circularly polarized light-emitting devices, mainly to realize high-performance CPL emission. These key challenges give rise to several promising research opportunities to facilitate the development of highly stable and high-performance CPL emitting devices, thus inspiring more possibilities for CPL display, cryptology, and anti-counterfeiting applications.