Construction of highly efficient bifunctional catalyst based on a g-C3N4-FeCoNi-LDH heterojunction for sensitive electrochemical sensing and rapid detoxification of 4-nitrophenol

The excessive reliance on traditional fossil fuels has not only triggered an energy shortage crisis but also caused severe environmental pollution. These pollutants can significant accumulate via the process of bioaccumulation within the food chain, ultimately posing a serious threat to human health. Therefore, the development of efficient and precise water quality monitoring technologies is crucial for the prevention and control of environmental pollution. In this study, a g-C 3 N 4 -FeCoNi layered double hydroxide (LDH) heterostructure material (g-C 3 N 4 -LDH) was successfully synthesized using a one-step hydrothermal method. The formation of an n–n heterojunction between g-C 3 N 4 and LDH facilitates efficient interfacial charge transfer and structural stabilization, which is critical for bifunctional applications. Consequently, the constructed g-C 3 N 4 -LDH sensing platform exhibits good performance in 4-NP detection, with a sensitivity of 0.664 μA·μM −1 ·cm −2 , a linear response range of 5–800 μM, and a low detection limit of 0.67 μM (S/N = 3). Moreover, the platform demonstrates strong resistance to interference and excellent stability. Additionally, g-C 3 N 4 -LDH can completely degrade 4-NP within 10 min, effectively detoxifying the pollutants. This study offers new insights and a solid foundation for the rapid and accurate detection and treatment of water pollutants.