Preparation and Application of Bismuth/MXene Nano-Composite as Electrochemical Sensor for Heavy Metal Ions Detection

Abstract

A nano-form composite of MXenes (Ti₃C₂T<i>_x</i>, T<i>_x</i> = -O, -OH, -F) was synthesized through depositing bismuth-nanoparticle (BiNPs) onto Ti₃C₂T<i>_x</i> sheets. Because of the preventive effect of the two-dimensional layered structure of Ti₃C₂T<i>_x</i>, the nanoparticles of Bi were uniform and well attached on the Ti₃C₂T<i>_x</i>. The obtained BiNPs/Ti₃C₂T<i>_x</i> nano-composite was applied for sensors construction of electrochemical detecting of Pb²⁺ and Cd²⁺ heavy metal ions. The produced BiNPs@Ti₃C₂T<i>_x</i>-based sensor showed high effective surface area and excellent conductivity. Also, the BiNPs were efficient for anodic-stripping voltammetric to detect heavy metal ions. After conditions optimization, the BiNPs@Ti₃C₂T<i>_x</i> nano-sensor could detect Pb²⁺ and Cd²⁺ simultaneously and the detection limits were 10.8 nM for Pb²⁺ and 12.4 nM for Cd²⁺. The BiNPs@Ti₃C₂T<i>_x</i> was promising for detecting heavy metal ions due to their high surface area, fast electron-transfer ability, environmental friendliness, and facial preparation.