MOF-derived NiWO4@NiO p-p heterostructure for distinguish detection of TEA and xylene by temperature regulation

Abstract Accurate detection of outdoor air quality requires a large number of gas sensors to be used in various fields. Thus, it is greatly significance to develop multifunctional sensors. In this work, the NiWO4 decorated NiO p-p type heterostructure were successfully synthesized using the metal organic framework (MOF) as a self-sacrificing template with annealing process. The gas sensitive measurements reveal that the 12 wt% NiWO4 decorated NiO based sensor exhibits the higher response value (65) than that of the pure NiO sensor (2.5) to 50 ppm triethylamine (TEA) at 240°C. The selectivity of the NiWO4 decorated NiO based sensors could be changed when the operating temperature over 260°C, and the 12 wt% NiWO4 decorated NiO based sensor shows the higher response value (28) than that of the pure NiO sensor (2) to 50 ppm xylene at 270°C, indicated that as-prepared the NiWO4 decorated NiO heterostructure can be as a promising material applied to fabricate the dual sensor to detect TEA and xylene with high sensitivity as well as distinguish by adjusting the temperature. The improved gas-sensing mechanisms of the NiWO4 decorated NiO based on sensor are discussed in detail.