Constructing ZnCo₂O₄ hierarchical porous architectures for enhanced xylene gas detection

The hollow porous tube assembled ZnCo2O4 hierarchical porous architectures (HPA) have been prepared by a solvothermal strategy and subsequent annealing treatment. Various techniques are employed for the characterization of the morphology, structure and surface area of as-prepared ZnCo2O4 HPA. To demonstrate its potential application, ZnCo2O4 HPA is fabricated to be gas sensors to test their gas sensing properties. The ZnCo2O4 HPA sensor shows an enhanced response, fast response/recovery speed (1 s/12 s) and well repeatability and stability toward xylene gas at a working temperature of 260 ?. Such xylene sensing behaviors are attributed to the appropriate catalytic activity of p-type semiconductor ZnCo2O4 and the distinctive hierarchical porous structures, which not only promote the oxidation of xylene and improve surface chemical reaction between chemisorbed oxygen ions and xylene gas, but also facilitate gas permeation and adsorption/desorption. ZnCo2O4 hierarchical porous architectures with high xylene sensing performances hold great prospect in the actual xylene gas detection.