Recent advances in enzyme-free electrochemical hydrogen peroxide sensors based on carbon hybrid nanocomposites

The significance of H2O2 in biological systems and its wide application in various areas, such as municipal wastewater treatment, aseptic packaging, etc., have enabled the development of simple, stable, and highly sensitive H2O2 sensors that have gained growing research interest. With the fast development of nanotechnology, the emergence of enzyme-free electrochemical H2O2 sensors based on efficient enzyme-mimetic electrocatalysts has opened up new horizons for researchers. Among them, carbon nanomaterials stand out from many nanomaterials with enzyme-like electrocatalytic activity due to their remarkable structural diversity, considerable cost-effectiveness, as well as fascinating and stable physicochemical properties. Importantly, carbon nanomaterials can act as nano-supports for other electrocatalysts in addition to being directly used as electrocatalysts. Moreover, the carbon hybrid nanocomposites tend to be superior to each component in electrochemical performance due to synergistic effects. Therefore, carbon hybrid nanocomposites are emerging as promising materials for highly efficient and sensitive enzyme-free electrochemical H2O2 detection. In this review, we overview the recent advances of carbon hybrid nanocomposites in enzyme-free electrochemical H2O2 sensing, covering the characteristics and performance of various carbon hybrid nanocomposites based on other electrocatalysts hybridized with carbon nanomaterials and the optimized design of carbon hybrid nanocomposites in improving the enzyme-free electrochemical detection of H2O2.