Search

Lead-free Cs3Cu2I5 metal halides have garnered significant attention recently due to their non-toxic properties and deep-blue emission. However, their relatively low photoluminescence quantum efficiency and poor stability have limited their applications. In this work, sodium iodide (NaI) is used to facilitate the synthesis of Cs3Cu2I5 nanocrystals (NCs), demonstrating improved photoluminescence intensity, photoluminescence quantum yield, and stability. Systematic optoelectronic characterizations confirm that Na+ is successfully incorporated into the Cs3Cu2I5 lattice without altering its crystal structure. The improved Photoluminescence Quantum Yield (PLQY) and stability are attributed to the strengthened chemical bonding, which effectively suppresses vacancy defects in the lattice. Additionally, light-emitting diodes (LEDs) based on 10% NaI-doped Cs3Cu2I5 NCs were assembled, emitting vibrant blue light with a maximum radiant intensity of 82 lux and Commission Internationale de l'Eclairage (CIE) chromaticity coordinates of (0.15, 0.1). This work opens new possibilities for commercial lighting display applications. [ABSTRACT FROM AUTHOR]

Carbon dots have received much attention due to their unique physicochemical properties and diverse applications in bioimaging, optoelectronic devices, catalysis, and agriculture. Here, in this work, we report a simple hydrothermal synthesis of nitrogen and phosphorus−doped carbon dots (N, P−CDs). The optical and physical properties of the synthesized N, P−CDs are analyzed using systematical spectroscopy and electrical characterization. The synthesized N, P−CDs show strong photoluminescence at 626 nm and demonstrate high stability under UV light and other conditions. Moreover, we incorporate the synthesized N, P−CDs into water spinach by root spraying and leaf spraying. It is found that N, P−CDs could effectively promote the growth of water spinach by accelerating the photosynthetic rate, and increasing the content of total phenols, anthocyanins, and flavonoids in water spinach. [ABSTRACT FROM AUTHOR]

Lead halide perovskite has become a promising candidate for high-performance photodetectors (PDs) due to its attractive optical and electrical properties, such as high optical absorption coefficient, high carrier mobility, and long carrier diffusion length. However, the presence of highly toxic lead in these devices has limited their practical applications and even hindered their progress toward commercialization. Therefore, the scientific community has been committed to searching for low-toxic and stable perovskite-type alternative materials. Lead-free double perovskite, which is still in the preliminary stage of exploration, has achieved inspiring results in recent years. In this review, we mainly focus on two types of lead-free double perovskite based on different Pb substitution strategies, including A2M(I)M(III)X6 and A2M(IV)X6. We review the research progress and prospects of lead-free double perovskite photodetectors in the past three years. More importantly, from the perspective of optimizing the inherent defects in materials and improving device performance, we propose some feasible pathways and make an encouraging perspective for the future development of lead-free double perovskite photodetectors. [ABSTRACT FROM AUTHOR]