Enhanced xylene sensing performance of hierarchical flower-like Co₃O₄ via In doping

Metal ions doping is a typical approach for tuning sensing properties of metal oxide semiconductors based gas sensors. Herein, hierarchical flower-like pure and In-doped Co₃O₄ nanostructures assembled by porous two-dimensional (2D) nanosheets are synthesized via a solvothermal method and annealing process. The sensing measurements display that the In@Co₃O₄-4 based sensor possesses high response value of 55.9 toward 100 ppm xylene at 150 °C, which is nearly 3.8 times larger than that of pure Co₃O₄ sensor. Furthermore, it possesses good selectivity and anti-humidity properties. Combined with the results of DFT calculations, the mechanism of enhanced gas sensing performance is analyzed systematically.