Formation and perspectives of metal halide hybrid glasses

Metal halide hybrids (MHH) crystalline materials have been widely applied in optoelectronic fields such as solar cells, light-emitting diodes, and photodetectors, owing to their excellent crystalline quality and efficient charge-carrier transport properties. Intriguingly, the emergence of MHH glasses with long-range disorder offers a unique pathway for property modulation. However, a comprehensive understanding of the developmental trajectory of MHH glasses and their composition-dependent glass-forming ability remains elusive in the academic community. In this perspective, starting from the fundamental knowledge for MHH glass formation, we systematically summarize the relationship between chemical structure design and the basic requirements for glass formation in current organic cation–metal ion systems, as well as the state-of-the-art application progress. Furthermore, we explore the correlation between organic cation configuration and the glass-forming ability of MHH glasses and highlight the advantages of the two-component mixing strategy in modulating the properties of MHH glasses. We also outline the challenges and corresponding solutions at each critical stage of structural design. Finally, we provide a perspective on the future development directions of the MHH glass family.