Enhancing Wide-Spectrum Blue Luminescence Efficiency and Stability in Bi3+-Doped Cs2zncl4 Nanocrystals from Stes and Advancing Energy Applications

Lead halide perovskites exhibit exceptional photovoltaic properties, rendering them highly promising for luminescence applications. However, the commercial viability of perovskites encounters significant hurdles primarily stemming from two concerns: lead toxicity and limited stability under ambient conditions. Consequently, the development of non-toxic and stable perovskite alternatives has become a pressing and pivotal objective in the realm of optoelectronic materials. This study presents a comprehensive examination of lead-free metal halide Cs2ZnCl4:Bi3+ nanocrystals (NCs) that emit blue light, exhibiting both stability and efficiency. By utilizing these nanocrystals as a luminescence down-shifting (LDS) layer in conjunction with commercial GaAs solar cell devices, we have successfully resolved the issue of weak absorption in short-wavelength silicon-based cells through down-conversion principles, consequently augmenting the photovoltaic conversion efficiency (PCE) of solar cells by approximately 1%. Additionally, the integration of Bi3+-doped Cs2ZnCl4 nanocrystals with 365 nm commercial LED chips enables the creation of broad-spectrum blue-emitting LED devices. Consequently, we firmly believe that all-inorganic metal halide Cs2ZnCl4:Bi3+ nanocrystals possess substantial potential for future applications in novel lead-free perovskite photovoltaics and LEDs.