A neural network-shaped composite of α-MnO2 with N-doped graphene for electrocatalytic reduction of hydrogen peroxide in human urine samples

Abstract

A neural network-shaped composite fusing α-MnO₂ and nitrogen-doped graphene (N@Gr/α-MnO₂) was synthesized via a hydrothermal method. The resulting composite demonstrates enhanced electrocatalytic activity for hydrogen peroxide (H₂O₂) compared with each single component. The electrochemical sensor developed with N@Gr/α-MnO₂ demonstrates a robust linear relationship over the concentration ranges of 0.05 μmol L⁻¹ to 0.625 mmol L⁻¹ and 0.77 to 8.27 mmol L⁻¹, as evaluated by chronoamperometry (CA). The limit of detection (LOD) for H₂O₂ was determined to be 1.4 × 10⁻⁸ mol L⁻¹ (S/N = 3), with a sensitivity of 1466.1 μA (mmol L⁻¹)⁻¹ cm⁻². Furthermore, the sensor has been successfully utilized to detect trace amounts of H₂O₂ in human urine samples, thereby providing valuable insights and strategies for the development of more sensitive electrochemical sensors.