Ultrasensitive Detection of Disinfection Byproduct Trichloroacetamide in Drinking Water with Ag Nanoprism@MoS2 Heterostructure-based Electrochemical Sensor

Abstract The chlorination disinfection of drinking water generates disinfection byproducts (DBPs), which are toxic, carcinogenic, mutagenic, and teratogenic. Recently, trichloroacetamide (TCAM) has been proved to be highly genotoxic and cytotoxic. In this study, a sensitive and selective electrochemical sensor for TCAM detection is reported that is based on the triangular silver nanoprism (AgNPR) and MoS2 nanosheet (AgNPR@MoS2) heterostructure. The AgNPR can catalyze the dechlorination reaction of TCAM; and the abundant S sites on the edge of MoS2 nanosheet can absorb H+, thereby accelerating the dechlorination hydrogenation reaction. The AgNPR@MoS2 heterostructure exhibits a high charge transfer rate, high electrocatalytic activity, and good stability in TCAM detection. The sensor shows two linear sensing ranges of 0.5−10 μM and 10−80 μM, a detection limit of 0.17 μM, and high specificity to coexist DBPs. This study is one of the first reports of electrochemical detection of TCAM, and has successfully demonstrated the significant potential of electrochemical sensor for the real-time analysis and monitoring of trace TCAM in drinking water.