Voltammetric Analysis of Thiamethoxam Based on Inexpensive Thick-Walled Moso Bamboo Biochar Nanocomposites

A simple and cheap thick-walled Moso biochar (BC) was selected and combined with carbonate minerals dolomite (DM) to construct a voltammetric sensing platform for application in stripping analysis of thiamethoxam in agricultural and environmental samples. The BC based on thick-walled Moso was prepared by pyrolyzing biomass wastes in limited oxygen atmosphere at temperatures of 600 °C for 2 h, and the BC-DM nanocomposite was obtained through milling and sieving, then liquidphase ultrasonic assistance by dispersing grinded DM and moso bamboo BC into ultra-pure water. The morphology and structure of the BC-DM nanocomposite were characterized by FT-IR, XRD, and SEM-EDX. Under optimal conditions, the BC-DM modified electrode showed high sensitivity and good stripping voltammetric response towards thiamethoxam in a linear range from 0.5 to 35 μg mL -1 with a limit of detection (LOD) of 0.22 μg mL -1 . The prepared nanocomposite sensor was employed for the determination of thiamethoxam in different real samples with acceptable recoveries. Thickwalled moso as biochar with post-modification provides a new promising platform for potential applications in electrochemistry.