Innovative Z-scheme MnV₂O₆/g-C₃N₄ nanocomposite: photocatalytic, electrocatalytic and biosensing properties

Herein, we report Z-scheme mediated pn-junction between manganese vanadate and graphitic carbon nitride, highlighting its photocatalytic degradation capabilities, hydrogen and oxygen evolution reactions and electrochemical biosensing efficacy towards ascorbic acid. The material was synthesized using a co-precipitation method followed by annealing and characterized through XRD, FESEM, FTIR, XPS, UV–visible spectroscopy and EIS in conjunction with Mott-Schottky analysis. The heterojunction demonstrates promising results for photocatalytic degradation of organic dyes. This work further discusses the carrier concentration, decay rate, cyclic stability and photocatalytic degradation mechanism. The results for HER and OER indicate the synthesized material's capability for oxygen and hydrogen production at commercial scale, with Tafel slope calculations providing additional insights. Electrochemical biosensing of ascorbic acid reveals that the material can detect low concentrations of ascorbic acid under various parameters. The results indicate that the material is highly suitable for environmental degradation, electrocatalytic production of hydrogen and oxygen and medical diagnostics such as electrochemical biosensing.