Colorimetric sensor assay for detection of hydrogen peroxide using green synthesis of silver chloride nanoparticles: Experimental and theoretical evidence

Green and cost-effective synthesis method for preparation of metal nanoparticles and their applications for development of simple sensing strategy are of great demand to research community. So that in the present study, we report a green route for synthesis of silver chloride nanoparticles (AgCl-NPs) using brown algae from the Persian Gulf. Then its application for colorimetric detection of hydrogen peroxide (H2O2) was investigated. Interestingly the alga extract was served as capping agent. Synthesized AgCl- NPs were characterized by UV–vis spectroscopy, powder X-ray diffraction, energy dispersive X-ray spectroscopy, while the morphology and size analysis were characterized by high resolution transmission electron microscopy and dynamic light scattering. Finally, after optimization of solution pH, a simple and facile approach was developed for the naked-eye detection of hydrogen peroxide. Moreover, a theoretical study of AgCl interaction with hydrogen peroxide in both gas and solvent phase was performed at density functional level of theory. Theoretical results indicated that electrostatic interaction plays an important role in degradation of silver chloride nanoparticles induced by catalytic decomposition of hydrogen peroxide. This phenomenon led to considerable change in the surface plasmon resonance band at 417 nm which depends on H2O2 concentration. The absorbance at 417 nm was found to be linearly dependent on the hydrogen peroxide concentration in the range of 1–120 μM, with limit of detection of 8.64 nM.