The SPE modified with rGO-Co₃O₄-Pt nanocomposites exhibits the highest redox activity compared to the bare electrode and electrodes modified with rGO, Co₃O₄, Pt, or rGO-Co₃O₄ composites. The CV results revealed that the bare SPE exhibited minimal redox activity, indicating its limited ability to catalyze the electrochemical reduction of H₂O₂. However, modification with rGO nanomaterial significantly enhanced catalytic activity due to its twodimensional structure . Similarly, Co₃O₄/SPE demonstrated improved charge transfer properties by providing Co²⁺/Co³⁺ sites that enhance electron transfer reactions, thereby boosting catalytic activity for H₂O₂ reduction . The presence of Pt nanoparticles enhances the catalytic reaction, promoting the direct reduction of H₂O₂ . The reduction of H₂O₂ at the rGO-Co₃O₄-Pt nanocomposite electrode is facilitated by the synergy of the conductive rGO matrix, redox-active Co₃O₄, and catalytically active Pt. The nanocomposite demonstrates high sensitivity, rapid electron transfer, and low potential, making it highly effective for electrochemical detection of H₂O₂. The reduction of H₂O₂ on the nanocomposite-modified electrode occurs through two simultaneous reactions at distinct active sites: