Gold Nanoparticle-Modified Electrodes for Electrochemical\nSensing of Ammonia Nitrogen in Water

Abstract

As a common water pollutant, ammonia\nnitrogen (aN) has adverse\neffects on human life and production. Therefore, it is of great significance\nto realize the precision prevention of aN. Here, gold nanoparticle\n(AuNP)-modified carbon cloth (CC) electrodes were prepared for aN\ndetection using cyclic voltammetry (CV). The first electrode was synthesized\nby in situ loading of AuNPs on the flexible CC (AuNPs/CC), and the\nsecond electrode was obtained by deposition of graphene coating on\nthis basis (AuNPs/CC@G). Their selective response to aN was attributed\nto the formation and transformation of the gold ammonia complex through\nthe electrodissolution of AuNPs. Two electrodes had a wide quantitative\nrange (0.001–10000 μM); meanwhile, the limits of detection\n(LoDs) were down to the nanomolar level. From the aN standard to a\nreal water sample, both nanocomposite electrodes also exhibited excellent\nsensing performance in the aspect of anti-interference, reusability,\nreproducibility, stability, and recovery. In the simultaneous comparison,\nthe superior results of AuNPs/CC@G have confirmed the realization\nof optimization, which provided an innovative solution for the efficient\nand accurate monitoring of aN in water.