Spectral adjustable Re-Cs3Cu2I5 nanocrystal-in-glass composite with long-term stability

Cs3Cu2I5 materials exhibit significant potential in diverse application fields like LEDs, scintillation, photoelectric detection, and so on. However, their poor stability against moisture /water and singularity nature of emission band hinder their rapid utilization. Differing from the lattice or ligand modification methods commonly used, this work deftly integrates solid-state sintering and glass composite techniques to synthesize Cs3Cu2I5 nanocrystal-in-glass composite (NGC) with exceptional stability. Cs3Cu2I5 NGC demonstrated remarkable stability, maintaining its integrity even after immersion in an aqueous solution for 240 h or exposure to air for 180 days. Importantly, this proposed fabrication approach further utilizes the high solubility of glass materials for rare earth elements to solve the problem of the low solid solubility of Re3+ in Cs3Cu2I5. The full-spectrum tunable emission has been achieved in the composite of Re3+ and Cs3Cu2I5 materials for the first time. This study not only validates Re-Cs3Cu2I5 NGC as a promising fluorescent material but also establishes a novel method for fabricating composite materials based on rare-earth and copper perovskites, along with verifying their suitability in optical applications such as anti-counterfeiting and temperature measurement.