Facile synthesis of Ti3C2Tx@gold nanoparticle-arginine and serine-functionalized graphene quantum dot aerogel for electrochemical detection of chloramphenicol

Ti3C2Tx has been extensively used as a promising sensing material for the construction of electrochemical sensors because of its excellent conductivity, surface area and mechanical properties, but the two-dimensional structure and poor catalytic activity of Ti3C2Tx limit the improvement of its analytical behavior. This paper reports a facile method for the synthesis of a Ti3C2Tx@gold nanoparticlearginine- and serine-functionalized graphene quantum dot aerogel (Ti3C2Tx@Au-AS-GQD). AS-GQD was prepared by heating a mixture of citric acid, arginine and serine. The formed AS-GQD was used to reduce chloroauric acid to produce gold nanoparticles. The gold nanoparticles protonated with hydrochloric acid were dropped into a Ti3C2Tx aqueous solution to form Ti3C2Tx@Au-AS-GQD. The Ti3C2Tx@Au-AS-GQD shows one three-dimensional structure. Small gold nanoparticles were uniformly dispersed on the Ti3C2Tx sheets. The introduction of AS-GQD resulted in the formation of Schottky heterojunction and enhanced the catalytic activity. The electrochemical sensor fabricated with Ti3C2Tx@Au-AS-GQD exhibited high sensitivity, selectivity and repeatability in the electrochemical detection of chloramphenicol. The differential pulse voltammetric current at similar to 0.6 V linearly increased with the increase in chloramphenicol within 0.003-100 mu M, exhibiting a detection limit of 0.0012 mM (S/N = 3). The sensitivity of our sensor toward chloramphenicol was better than those of other electrochemical sensors. This study also paves an avenue for the construction of Ti3C2Tx composites with excellent catalytic activity in sensing, catalysis and energy storage and conversion.

Automated summary

This paper presents a facile method for synthesizing Ti3C2Tx@gold nanoparticle-arginine- and serine-functionalized graphene quantum dot aerogel. The synthesized material exhibited high sensitivity, selectivity, and repeatability in electrochemical detection, making it a promising candidate for sensing, catalysis, and energy storage and conversion applications.