Effect of Pulsed Laser Irradiation on Perovskite/TiO2 Nanoparticles

Abstract

Perovskite layers are key nanoscale absorbers in a wide range of optoelectronic devices, driving intense research into their deposition control, crystallization kinetics, and interfacial nanoengineering. In this work, we investigate the effects of nanosecond-pulsed Nd:YVO₄ laser irradiation (355 nm) on the structural and optical properties of perovskite layers integrated with TiO₂ nanoparticles. Nanoscale modifications induced by laser processing are systematically analyzed through optical transmission, photoluminescence (PL), surface morphology, and elemental composition measurements. The results reveal laser fluence as a decisive parameter: Low fluence deteriorates optoelectronic performance by forming a defective surface dead layer via increased nanoscale roughness, whereas higher fluence enhances optical transmittance through controlled nanoscale ablation and film thinning. Moreover, the incorporation of a mesoporous TiO₂ nanoparticle scaffold plays a critical role in maintaining bandgap stability during laser exposure, underscoring its protective function against localized thermal decomposition. These findings demonstrate that laser-matter interactions at the nanoscale can be precisely tuned to engineer perovskite layers for targeted optoelectronic device applications.