“…Generally, RT sensing materials should possess two basic attributes: high carrier mobility at RT and obvious change of resistance after adsorption/desorption of the target gas. Currently, numerous materials are found to be active for RT detection of NO 2 , such as metal oxides with unique structures, 5 graphene, 6 transition metal dichalcogenides, 7 transition metal diselenides, 8 black phosphorus, 9 MXenes, 10 covalent organic frameworks, 11 and hydrogels. 12 Owing to obvious gas response properties and good compatibility with electronic devices, reduced graphene oxide (rGO) has become one of the most promising candidates for RT NO 2 sensors.…”