A novel MnO-CrN nanocomposite based non-enzymatic hydrogen peroxide sensor

A MnO-CrN composite was obtained via the ammonolysis of the low-cost nitride precursors Cr(NO₃)₃·9H₂O and Mn(NO₃)₂·4H₂O at 800 °C for 8 h using a sol-gel method. The specific surface area of the synthesized powder was measured via BET analysis and it was found to be 262 m² g^-1. Regarding its application, the electrochemical sensing performance toward hydrogen peroxide (H₂O₂) was studied via applying cyclic voltammetry (CV) and amperometry (i-t) analysis. The linear response range was 0.33-15 000 μM with a correlation coefficient (R ²) value of 0.995. Excellent performance toward H₂O₂ was observed with a limit of detection of 0.059 μM, a limit of quantification of 0.199 μM, and sensitivity of 2156.25 μA mM^-1 cm^-2. A short response time of within 2 s was achieved. Hence, we develop and offer an efficient approach for synthesizing a new cost-efficient material for H₂O₂ sensing.