Preparation of High-Efficiency Light Emitters Based on Copper and Silver Halides

The recent discovery of novel families of high-efficiency light emitters based on all-inorganic copper(I) halides has been an important step forward in both realization of alternative non-Pb light emitters for practical applications and studies of photophysical properties of a brand-new metal halide system with unique crystal structures. These all-inorganic copper(I) halides demonstrate low-dimensional non-perovskite structures, often based on tetrahedral coordination around copper, and consequently, exhibit very flat bands around the optical gap, leading to very localized charges and enhanced emission attributed to the presence of high stability self-trapped excitons (STEs) at room temperature. Although copper(I) halides combine some of the most desirable attributes for practical applications such as light emission efficiencies up to 100%, non-toxic and earth-abundant chemical compositions, most copper(I) halides must be handled carefully as they are prone to degradation in ambient air (e.g., via oxidation to copper(II) species). Additionally, copper(I) halides are found to exhibit photoemission in the blue region with an unusually poor tunability of the optical emission and absorption properties. In this talk, we will summarize our recent work aimed at improving both environmental stability and tunability of optical properties of our high-efficiency copper(I) halides through silver substitution and preparation of series of hybrid organic-inorganic copper(I) halides.