Enhanced Photocatalytic and Photoluminescence Properties of NiS Doped with Pr3+ for Efficient Dye Degradation: Kinetics and Isotherm Studies

This study presents the successful synthesis of NiS doped with Pr³⁺ nanoparticles via the reflux method, followed by characterization techniques such as XRD, SEM, TEM, FTIR, BET, Raman, PL, and UV–vis spectroscopy. The nanoparticles exhibited particle sizes ranging from 12 to 19 nm using the Scherrer equation. EDX analysis confirmed the presence of Ni, S, and Pr, verifying the successful incorporation of Pr³⁺. When excited at 424 nm, the photoluminescence emission spectrum shows electronic transitions such as ³P₁ → ³H₅, ³P₀ → ³H₅, ¹D₂ → ³H₄, ³P₀ → ³F₂. Chromaticity (CIE) of the doped samples at varying Pr³⁺ concentrations indicates the potential for white light emission, highlighting their applicability in solid-state lighting. BET analysis reveals a notable increase in surface area with higher Pr³⁺ doping levels. NiS doped with Pr³⁺ nanoparticles demonstrate excellent photocatalytic degradation efficiencies under UV light, achieving 96% degradation of rhodamine B, 92% of methylene blue, 95% of methyl orange, and 94% of congo red within 90 min, and follow pseudo-first-order kinetics. This study offers a detailed evaluation of the influence of Pr³⁺ doping on the luminescent and photocatalytic performance of NiS nanoparticles, underscoring their potential for environmental remediation and optoelectronic applications.