Facile preparation of urchin-like NiCo2O4 microspheres for efficient hydrogen peroxide detection

In this work, urchin-like NiCo2O4 microspheres were prepared via a facile ionic liquid-assisted hydrothermal synthesis and used as non-enzymatic H2O2 sensors for the first time. The porous structure and high surface area of the NiCo2O4 microspheres provide plentiful active sites for electrocatalytic H2O2 oxidation. When adapted into an electrochemical sensor for H2O2, the microsensors showed fast response of 4 s, a high sensitivity of 392.5 μA·mM−1 cm−2, and a wide linear range towards H2O2 (0–14 mM). The detection limit was as low as 0.05 μM, significantly lower than other published high performance NiCo2O4-based H2O2 sensors. Furthermore, this non-enzymatic sensor exhibits good selectivity for H2O2. These results suggest that NiCo2O4 microspheres could be a promising material for trace H2O2 detection.