Ammonia nitrogen is a key indicator for evaluating drinking water quality, and its accurate determination is of great significance for environmental monitoring and public health protection. In this work, a self-supported electrochemical sensor based on PtCo alloy nanosheets was fabricated on carbon cloth via a one-step electrodeposition strategy. The nanosheet structure facilitates the exposure of abundant electroactive sites and promotes efficient electron transfer. Electrochemical measurements indicate that the PtCo/CC electrode exhibits higher electrocatalytic activity toward ammonia oxidation than monometallic Pt, which can be attributed to the modulation of the Pt electronic structure induced by Co incorporation. Under linear sweep voltammetry, the optimized electrode exhibits a high sensitivity of 32.94 μA μM−1 cm−2 in the concentration range of 0.7–10 μM and 11.43 μA μM−1 cm−2 in the range of 10–100 μM, with a low detection limit of 77.9 nM. In addition, the electrode maintains good selectivity in the presence of common interfering ions, along with satisfactory reproducibility and stability. The feasibility of practical application is further confirmed by real water sample analysis. Overall, this work provides an effective strategy for the design of Pt-based alloy electrodes for ammonia nitrogen detection, with potential applications in drinking water quality monitoring.
Zhuang et al. (Thu,) studied this question.