The enhanced xylene gas sensing selectivity in p-type CuCo2O4 hierarchical architectures

Realizing high selective detection toward the target gas is one of the most important evaluation indexes of the gas sensors. Revealing the dominant factor affecting sensing selectivity has always been the focus and keynote of gas sensing research fields and the hinge to optimize material selectivity. In this manuscript, a series of CuCo ₂O ₄ based gas sensing materials have been prepared by annealing CuCo ₂O ₄ precursors synthesized by a feasible hydrothermal reaction. The gas sensor based on CCO-400 (CuCo ₂O ₄ annealed at 400 °C) shows superior selectivity toward xylene gas at a working temperature of 150 °C. Meanwhile, the CCO-400 sensor also presents well stability, repeatability and a low detection limit of 0.5 ppm. The enhanced xylene gas sensing selectivity of the CCO-400 sensor is prominently attributed to the catalytic promotion of the Co component toward xylene gas, advancing the dissociation of the less reactive xylene.