Kinetics and thermodynamics studies of nickel manganite nanoparticle as photocatalyst and fuel additive

In this study, nickel manganite (NiMn₂O₄) nanoparticles were prepared using a hydrothermal method and examined its potential as a photocatalyst for the Acid Green 25 (AG-25) dye degradation. The nanoparticles were subjected to structural analysis using X-ray diffraction (XRD) and morphological analysis using scanning electron microscopy (SEM). The study examined the kinetics and thermodynamics of degradation processes that are catalyzed by photocatalysis. To ascertain their effect on dye degradation, several parameters, such as catalyst dose, H₂O₂ concentration, and temperature, were investigated. With a temperature of 315 K in a pseudo-first-order kinetic reaction, a 0.3 M H₂O₂ concentration, 0.05 mg/mL catalyst dose, and a promising removal efficiency of 96 % was achieved by the NiMn₂O₄ NPs in 40 min. Thermodynamic analysis revealed the spontaneous and entropy-driven nature of catalytic degradation, progressing favorably at elevated temperatures. Additionally, the NiMn₂O₄ NPs were applied as a fuel additive to analyze its influence on combustion and the physical characteristics of the modified fuel. The modified fuel demonstrated exceptional catalytic efficiency, emphasizing the potential of the NiMn₂O₄ NPs as an effective additive.