▎ 摘　　要

Nitrite has been widely used in industrial and agricultural production and commonly exists in food, drinking water, organisms and the environment. However, nitrite is a toxic contaminant that can be very harmful to humans. In recent years, various methods for detecting nitrite have been developed, among which electrochemical methods are favored for their simplicity, rapidity, sensitivity and low price. In this paper, a graphene supported nano-PdCo alloy catalyst is proposed for the preparation of electrochemical nitrite sensor. The results show that the as-prepared sensor has a good electrocatalytic effect on the detection of nitrite. The electrochemical sensor can be adopted for rapid detection of nitrite with a wide range of 20 similar to 1050 mu M and the low detection limit of 7.7 nM. The proposed sensor has been successfully applied to the detection of nitrite in pure water, with the recovery rate being 99.17% to 107.24%, which indicates that the sensor has good stability and reproducibility.