“…The obvious solution to overcome these problems associated with both metal oxides and rGO is to blend them together to gain the advantage of their important properties, leading to the generation of heterostructures or composites. So far, various rGO-metal oxide-based heterostructures/composites such as rGO-SnO 2, rGO-Co 3 O 4, rGO-ZnO, rGO-WO 3, rGO-Cu 2 O, rGO-NiO, rGO-MoO 3 , and rGO-TiO 2 have been explored for the detection of gases and other analytes. Among them, rGO-TiO 2 composites have been reported for the sensing of different gases and vapors such as NO, NH 3 , ethanol, methanol, acetone, etc. − …”