Exploring Mg2+ doped CoCr2O4 Nanoparticles: Eco-Friendly Pigments, radiation dosimeters and latent fingerprint visualization

Abstract

This research investigates the impact of Mg²⁺ doping in CoCr₂O₄ nanoparticles (NPs) to address the challenges of toxicity and cost of cobalts, targeting applications in green ceramic pigments and radiation dosimetry. Mg_xCo_1-xCr₂O₄ (x = 0.0, 0.05, 0.1, 0.15, 0.2 and 0.25) NPs are synthesized using a solution combustion method. Thermoluminescence (TL) studies conducted on these NPs under varying gamma (γ) radiation doses (1–100 Gy, Co-60 γ-source) revealed a proportional increase in TL peak intensity with dose, establishing a robust linear dose–response relationship. The TL glow curves exhibited three prominent peaks, primarily at ∼ 190 °C, 240 °C, and 335 °C, indicative of distinct trap levels in the NPs matrix. The primary peaks near 190 °C and 240 °C are dominant, with a minor secondary peak around 335 °C. Advanced analytical techniques, including Computerized Glow Curve Deconvolution (CGCD) and Chens Peak Shape Method (PSM), are utilized to extract activation energies and trapping parameters, confirming general order kinetics for the glow curves. Consistency in activation energy values across methods underscored the study reliability. These findings position Mg²⁺ doped CoCr₂O₄ NPs as promising materials for radiation dosimetry. Additionally, optimized Mg_0.15Co_0.85Cr₂O₄ NPs demonstrated efficient latent fingerprints (LFPs) detection on diverse surfaces using a simple powder application method. Further analysis of pore characteristics, such as count, positioning, dimensions, and spacing, is conducted. A Python-based mathematical model analyzed Level I–II ridge features, successfully deciphering details from single and overlapping fingerprints (FPs), offering valuable insights into structural patterns.