A covalent organic frameworks@gold nanoparticles@graphene nanocomposite based electrochemical sensor for simultaneous determination of trace Cd2+, Pb2+ and Cu2+

It's very exciting to develop an electrochemical sensor for simple, rapid and simultaneous determination of heavy metal ions in Baijiu by applying new nanocomposites. Herein, a novel COF DPTB @gold nanoparticles (AuNPs)@graphene (GR) was obtained via combining COF DPTB synthesized using the Schiff-base condensation between 2, 5-dimethoxyterephthalaldehyde and 1, 3, 5-tris(4-aminophenyl) benzene with AuNPs and GR. Owing to the high porosity and abundant adsorption sites of COF DPTB , the outstanding electrical conductivity of AuNPs and GR, as well as the high specific area and synergy of COF DPTB , AuNPs and GR, the proposed sensor exhibited excellent analysis performance for the detection of Cd 2+ , Pb 2+ and Cu 2+ . Under optimized conditions, the sensor showed good linearity range of 0.5–18 μM for Cd 2+ , and both 0.5–6.0 μM for Pb 2+ and Cu 2+ with the detection limits of 3.025 nM, 5.849 nM and 9.993 nM, respectively. In addition, the recovery measurement suggested the practicality of the prepared sensor.