Conductometric n-butanol gas sensor based on Tourmaline@ZnO hierarchical micro-nanostructures

[Display omitted] •Tourmaline@ZnO composites we have devised and achieved with fancy hierarchical micro-nanostructures revealed superior gas sensing performance.•The tourmaline inner core is of great significance to enhance gas sensibility with contrast to pure ZnO.•The surface electric field of tourmaline has not only reduced the recombination rate of electron-hole pairs, but also facilitated the transfer ability of interface charges.•The introduction of tourmaline enlarged the specific surface area of ZnO material, provide more active sites, which is conducive to the enchancement of gas sensitivity. The combinative strategy of metal oxide hybridized with other material to build up an effective heterojunction provides a promising route for the well development of the electronic devices. In this research, a conductometric sensor based on unique Tourmaline@ZnO core-shell structure for gas detection was successfully realized by synthesis of uniform precipitation and post-heat treatment. The structure, morphology, surface and energy band of the obtained sensing composites were successively characterized by XRD, SEM, TEM, BET, XPS and UV–vis analysis. The measuring results revealed a hierarchical grain-sheet-flower micro-nanostructure. Compared with pure ZnO, the Tourmaline@ZnO revealed larger specific surface area, richer oxygen vacancies and narrower band gap. Moreover, the gas sensing tests demonstrated that the core-shelled composites exhibited an excellent gas sensitivity to n-butanol, the sensor made from 1%Tourmaline@ZnO achieved the optimized performance as high as 120.84 to 100 ppm n-butanol that of 5 times more than other gases, additionally with the shortest response and recovery time. The introduction of tourmaline core exerted certain effects on the carrier migration and transmission performance, the micro-nanostructured Tourmaline@ZnO has confirmed to be a potential candidate for the detection of n-butanol and may play an important role in designing and fabricating highly efficient electronic sensors.