The contamination of industrial water sources with synthetic dyes, such as methylene blue (MB), remains a persistent environmental concern, demanding effective remediation techniques. In response, this research centers on the utilization of trimetallic nanoparticles (TMNPs) composed of Fe-Ni-Cr, Fe-Ni-Cd and Fe-Ni-Cu as a promising solution to address color-related pollution in aquatic ecosystems. These nanoparticles were synthesized using the wet chemical precipitation method and rigorously characterized using Fourier transform infrared (FT-IR), energy-dispersive X-rays (EDX), and scanning electron microscopy (SEM). Armed with these trimetallic nanoparticles, our primary objective was to harness their photocatalytic prowess when exposed to direct sunlight in aqueous environments for the degradation of MB. The progress of photodegradation was meticulously monitored using a reliable visible spectrophotometer, providing insights into the degradation kinetics. Remarkably, within just six hours of solar irradiation, the TMNPs exhibited a remarkable capacity to degrade MB, achieving an impressive degradation rate ranging from 77.5% to 79.4%. In our relentless pursuit of optimization, we conducted a comprehensive examination of various parameters including catalyst dosage, dye dosage, and pH levels, focusing specifically on the Fe-Ni-Cr TMNPs. Through systematic experimentation, a trifecta of optimal conditions emerged: a pH level of 10 (resulting in a 79.35% degradation after 1.5 h), a catalyst amount of 0.005 g (yielding 43.5% degradation after 1.5 h), and a dye concentration of 40.0 ppm (culminating in a 42.54% degradation after 1.5 h). The study also extended its scope to explore the regeneration potential of the catalyst, shedding light on its sustainability in long-term applications. Amidst the vibrant interplay of color and water, TMNPs emerged as a symbol of optimism, offering a promising avenue for the removal of synthetic dyes from the water system. With each experiment and investigation, we inch closer to realizing clearer waters and brighter environmental horizons.

A simple electrochemical paper-based sensor (ePAS) using mPEG-b-PLG/CdO quantum dots enabled selective glycine detection. Wax-printed channels and carbon/silver electrodes made this green, reusable, and low-cost platform suitable for real samples.