▎ 摘　　要

Herein, room-temperature NO2 gas sensor based on supramolecularly assembled isonicotinamide-graphene oxide nanocomposite (Iso-rGO) and Iso-rGO/Carbon felt (CF) electrode was prepared and studied. The morphology of the synthesized Iso-rGO nanocomposite was studied by field emission scanning electron microscopy (SEM), which revealed the uniform coating of isonicotinamide over the surface of the composite. Further studies confirmed the supramolecular functionalization assembly of isonicotinamide onto the surface of GO. The prepared nanocomposite was used as functional electrode material to fabricate room-temperature NO2 gas sensor. The fabricated electrode (Iso-rGO/CF) exhibited excellent reductive behavior of NO2 gas at room-temperature. The fabricated sensor exhibited a linear range from 1-30 ppm and a low detection limit (LOD) of 1 ppm towards NO2 gas. The NO2 sensitivity of the Iso-rGO/CF electrode is well correlated with online gas chromatography which demonstrate high sensitivity and good stability for more than 30 days. The observed results revealed that the proposed Iso-rGO/CF electrode could be a suitable sensor electrode for the sensitive detection of gaseous NO2 in the real samples. (C) 2021 The Authors. Published by Elsevier B.V.