Heterostructures of mesoporous hollow Zn2SnO4/SnO2 microboxes for high-performance acetone sensors

Metal oxide Semiconductors with porous hollow heterostructures can provide significant advantages for gas sensing by facilitating the increase of free electron density and the diffusion of target gases. Herein, mesoporous hollow Zn2SnO4/SnO2 microboxes were successfully synthesized by using a facile ZnSn(OH)6-sacrificial template method. In synergy with the special mesoporous hollow structure and the n-n heterojunction formed between Zn2SnO4 and SnO2, the Zn2SnO4/SnO2 composites exhibited excellent acetone-sensing properties. Compared with the pure SnO2 sensor, the Zn2SnO4/SnO2 sensor not only displayed a 2 times higher response (20.1) toward 100 ppm acetone as well as excellent selectivity and stability at the optimal operating temperature of 250 °C, but still maintained a perceived response (2.4) even when the concentration of acetone was down to 1 ppm. In addition, the enhanced sensing mechanism of Zn2SnO4/SnO2 microboxes was also discussed in detail. This work indicates that the mesoporous hollow Zn2SnO4/SnO2 microboxes can be very promising sensing material for the application of acetone gas sensors.