High‐performance flexible sensing devices based on polyaniline/MXene nanocomposites

Highly active two‐dimensional (2D) nanocomposites, integrating the unique merits of individual components and synergistic effects of composites, are greatly desired for flexible sensing device applications. Although 2D transition metal carbides and nitrides (MXenes) combined with their high metallic conductivity and versatile surface chemistry have shown its huge potential for sensing reactions, it still remains a major challenge to construct functional materials with intriguing sensing performance at room temperature (RT). Herein, we used an integration of density functional theory (DFT) simulations and bulk electrosensitive measurements to show high electrocatalytic sensitivity of polyaniline/MXene (PANI/Ti3C2T x) nanocomposites. Thanks to the synergistic properties of nanocomposites and high catalytic/absorption capacity of Ti3C2T x MXene, PANI nanoparticles are rationally decorated on Ti3C2T x nanosheet surface via in situ polymerization by low temperature approach to induce remarkable detection sensitivity, rapid response/recovery rate, and mechanical stability at RT. This study offers a versatile platform to use MXenes to fabricate 2D nanocomposites materials for high‐performance flexible gas sensors. Highly active two‐dimensional (2D) nanocomposites (PANI/Ti3C2T x) provide lasting inspiration and a promising avenue for designing advanced nanomaterials with new physicochemical properties. As a result, flexible gas sensors based on PANI/Ti3C2T x nanocomposites with highly active and synergistic properties have higher sensitivity and rapider response/recovery rate than pristine Ti3C2T x sensors for the detection of ethanol gas at room temperature.