Large interlayer spacing Nb₄C₃T_x (MXene) promotes the ultrasensitive electrochemical detection of Pb²⁺ on glassy carbon electrodes

Abstract

A Nb₄C₃T _<i>x</i> (MXene)-modified glassy carbon electrode was used for the electrochemical detection of Pb²⁺ ions in aqueous media. The sensing platform was evaluated by anodic stripping analysis after optimizing the influencing factors such as pH, deposition potential, and time. The large interlayer spacing, high <i>c</i> lattice parameter and higher conductivity of Nb₄C₃T _<i>x</i> compared to other MXenes enhance the electrochemical detection of Pb²⁺. The developed sensor can reach a detection limit of 12 nM at a potential ∼-0.6 V. Additionally, the developed sensor showed promising selectivity in the presence of Cu²⁺ and Cd²⁺, and stability for at least 5 cycles of continuous measurements with good repeatability. This work demonstrates the potential applications of Nb₄C₃T _<i>x</i> towards the development of effective electrochemical sensors.