Ethylcellulose-Encapsulated Inorganic Lead Halide Perovskite Nanoparticles for Printing and Optoelectronic Applications

Inorganic lead halide perovskite nanoparticles (NPs) have attracted attention for next-generation optoelectronics and anti-counterfeiting applications. The fully inorganic NPs get degraded in polar solvents resulting in poor stability. These also tend to degrade under exposure to high temperatures resulting in obstacles to application in reliable anti-counterfeiting and optoelectronics applications. The encapsulation of perovskite NPs with ethyl cellulose (EC) as a polymer matrix to overcome these obstacles is explored using a facile solution blending technique followed by ultra-sonication and characterization. These NPs demonstrate enhanced photoluminescence (PL) intensity, improved color clarity, and considerable stability. Along with organic binders, they can be used in developing printable ink for making patterns. A logo coated with CsPbBr₃ + EC and CsPbBr_1.5 I_1.5 + EC exposed in normal light and UV light (365 nm) shows a clear image that becomes blue-green and yellow color. Additionally, the effect of light on the current density–voltage characteristics of the size-dependent encapsulated NPs shows that photocurrent has dramatically improved over 5.14 times in CsPbBr₃ + EC and 1.68 times in CsPbBr_1.5 I_1.5 + EC compared to that of pristine one. These results demonstrate its potential uses for several applications such as luminescent printing applications, sensors, and optoelectronic applications.