In the present report, we employed a single-step simpler pyrolytic process for synthesizing magnetic graphene nanosheets (m-GNS) using expired iron-supplemented tablets. The microscopic morphological results showed the formation of multilayered graphene nanosheets (m-GNS) doped with iron oxide nanoparticles that impart magnetic behavior. m-GNS are used here as advanced oxidative materials to break down an azo dye named acid orange 7 (AO7). In the presence of sunlight, the rate of photodegradation of the AO7 dye is seven times faster than that under artificial light (visible and infrared), which significantly advocates the influence of sunlight. Based on trapping experiments, the production of hydroxyl radicals under sunlight has majorly been responsible for the photodegradation of the AO7 dye. A comparative nuclear magnetic resonance analysis was performed to support the breaking down of the complex organic framework of AO7 dyes into low-molecular-weight hydrocarbons.