Prussian Blue analogue derived porous NiFe2O4 nanocubes for low-concentration acetone sensing at low working temperature

Abstract

Real-time detection of acetone vapor at low concentration plays a decisive role in early noninvasive diagnosis of diabetes. In this work, porous NiFe2O4 crystalline nanocubes have been scalably prepared via an as-developed cost-efficient and facile strategy, which involves a morphology-inherited annealing treatment of single-resource Prussian Blue analogue of Ni3[Fe(CN)6]2·xH2O solid nanocubes as self-sacrificial templates. The porous NiFe2O4 crystalline nanocubes are demonstrated to be composed of primary nano building blocks and interconnected pores. When utilized as sensing materials, the as-synthesized NiFe2O4 exhibited p-type gas-sensing behavior that the resistance increases in a reducing gas atmosphere. Furthermore, the as-fabricated NiFe2O4 sensor was sensitive and selective to acetone gas with an obvious response value of 1.9 at its low concentration (1 ppm) and low detection of limit (0.52 ppm) at a quite low working temperature (160 °C). In addition, the sensing mechanism is deeply investigated. More significantly, our prominent findings herein shed light on the fabrication of metal oxide based gas sensors in environmental and medicinal fields.