Recent Progress on Synthesis, Characterization, and Applications of Metal Halide Perovskites@Metal Oxide

Metal halide perovskites (MHPs) have become a promising candidate in a myriad of applications, such as light-emitting diodes, solar cells, lasing, photodetectors, photocatalysis, transistors, etc. This is related to the synergy of their excellent features, including high photoluminescence quantum yields, narrow and tunable emission, long charge carrier lifetimes, broad absorption spectrum along with high extinction absorptions coefficients, among others. However, the main bottleneck is the poor stability of the MHPs under ambient conditions. This is imposing severe restrictions with respect to their industrialized applications and commercialization. In this context, metal oxide (MO_x) coatings have recently emerged as an efficient strategy toward overcoming the stabilities issues as well as retaining the excellent properties of the MHPs, and therefore facilitate the development of the related devices’ stabilities and performances. This review provides a summary of the recent progress on synthetic methods, enhanced features, the techniques to assess the MHPs@MO_x composites, and applications of the MHPs@MO_x. Specially, novel approaches to fabricate the composites and new applications of the composites are also reported in this review for the first time. This is rounded by a critical outlook about the current MHPs’ stability issues and the further direction to ensure a bright future of MHPs@MO_x.