The development of efficient photocatalysts for wastewater remediation is often hindered by time-intensive degradation experiments. This study introduces a novel, high-throughput screening protocol using Ice-Temperature Irradiated Thermoluminescence (ITI-TL) to predict the photocatalytic potential of orthorhombic CaSO \(_{4}\) :Dy nanophosphors synthesized via sol-gel and co-precipitation methods. While traditional X-ray diffraction (XRD) and scanning electron microscopy (SEM) confirmed phase purity and morphological evolution, they fail to quantify the real-time charge carrier dynamics essential for catalysis. Our results demonstrate that ITI-TL provides a direct “window” into these dynamics by measuring initial electron-hole (e-h) pair concentration and thermal stability. The sample synthesized via co-precipitation and annealed at 900 \(^{\circ }\) C exhibited the highest initial carrier density ( \(8.3 \times 10^{5}\) counts) and superior thermal retention (50.1% loss at 100 °C), which directly correlated with a peak Methylene Blue degradation efficiency of 90% and the fastest pseudo-first-order kinetics. Conversely, samples with lower ITI-TL stability demonstrated reduced catalytic performance. A Spearman rank correlation of the composite ITI-TL index (carrier density and thermal loss) against MB degradation efficiency yielded \(\rho = 0.95\) , providing formal statistical validation of the screening framework. This work validates ITI-TL as a transformative diagnostic tool capable of estimating a material’s environmental remediation potential in minutes rather than hours, streamlining the discovery of next-generation persistent phosphors.
