Effect of the oleylamine on non-stoichiometric crystal growth for Cs–Cu-X (X = Br, I) ternary system based microcrystal

In response to regulations on material specifications for commercial applications requiring specific optical properties, researchers have developed lead-free materials over the past decade as alternatives to lead-based halide perovskite materials. An in-depth investigation into material composition has revealed various trends in the emission mechanism, showcasing significant potential characterized by distinctive features. This paper explores the inorganic cesium copper halide (ICCH) materials characterized by self-trapped exciton (STE) derived from 0D and 1D isolated metal halide structures. Our optical analyses indicate a predominant role of STE in influencing the optical properties. Further, we investigated the non-stoichiometric growth mechanism and identified its association with Cu⁺-OLA (oleylamine). The fabricated transition-metal dichalcogenides (TMD)-based photodetector demonstrated enhanced performance using the 1D structured CsCu₂X₃ composition under 365 nm irradiation, attributed to its reduced electron-localization properties.