Controlled Synthesis of Hierarchically Assembled Porous ZnO Microspheres with Enhanced Gas-Sensing Properties

Figure 8

(a) Effect of operating temperature on the gas response of porous ZnO microspheres to 50 ppm ethanol gas. (b) Selectivity of porous ZnO microspheres to different testing gases. (c) Selectivity of ZnO microspheres versus testing gases concentration. (d) Response and recovery curves of porous ZnO microspheres upon exposure to ethanol gas.

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