Critical Addition Point-Based Trace Sensing of Hg²⁺ Through Surface Plasma Polaritons Properties Analysis of Ag Nanoparticles

In this work, we synthesize and functionalize Ag nanoparticles (NPs) with Sodium tripolyphosphate in one pot. Due to P-3 O-10(5-) _AgNPs aggregation in the presenceofmercury, colorimetric detection with naked eye realize, the limit of detection is 1 mu mol.L-1. Based on one critical additional point with 3 mu mol.L-1 of Hg2+ added, trace sensing of mercury can be performed through absorption spectra analysis, the limit of detection reaches 1nmol.L-1. The TEM image and EDS test tell the mechanism, where the aggregating behavior of P-3 O-10(5-) _AgNPs in the presence of Hg2+ is different from that of Cr3+ and Mn2+. Also, this method possesses high selectivity. This work may pave a facile way in mercury detection sensors.