Template Based Synthesis of Porous Graphdiyne Nanosheet for Reversible and Fast NO₂ Detection by UV Irradiation

Two-dimensional graphdiyne (GDY) formed by sp and sp² hybridized carbon has been found to be an efficient toxic gas sensing material by density functional theory (DFT). However, little experimental research concerning its gas sensing capability has been reported owing to the complex preparation process and harsh experimental conditions. Herein, porous GDY nanosheets are successfully synthesized through a facile solvothermal synthesis technique by using CuO microspheres (MSs) as both template and source of catalyst. The porous GDY nanosheets exhibit a broadband optical absorption, rendering it suitable for the light-driven optoelectronic gas sensing applications. The GDY-based gas sensor was demonstrated to have excellent reversible to NO₂ behaviors at 25 °C for the first time. More importantly, higher response value and faster response-recovery time once exposed to NO₂ gas molecules are achieved by the illumination of UV light. In this way, our work paves the way for the exploration of GDY-based gas detection experimentally.