Abstract: | A novel non‐enzymatic nitrite sensor was fabricated by immobilizing MnOOH‐PANI nanocomposites on a gold electrode (Au electrode). The morphology and composition of the nanocomposites were investigated by transmission electron microscopy (TEM ) and Fourier transform infrared spectrum (FTIR ). The electrochemical results showed that the sensor possessed excellent electrocatalytic ability for NO2− oxidation. The sensor displayed a linear range from 3.0 μmol•L−1 to 76.0 mmol•L−1 with a detection limit of 0.9 μmol•L−1 (S/N = 3), a sensitivity of 132.2 μA •L•mol−1•cm−2 and a response time of 3 s. Furthermore, the sensor showed good reproducibility and long‐term stability. It is expected that the MnOOH‐PANI nanocomposites could be applied for more active sensors and used in practice for nitrite sensing. |