International Journal of Molecular Sciences (Jun 2021)
Enhanced Sensing Ability of Brush-Like Fe<sub>2</sub>O<sub>3</sub>-ZnO Nanostructures towards NO<sub>2</sub> Gas via Manipulating Material Synergistic Effect
Abstract
Brush-like α-Fe2O3–ZnO heterostructures were synthesized through a sputtering ZnO seed-assisted hydrothermal growth method. The resulting heterostructures consisted of α-Fe2O3 rod templates and ZnO branched crystals with an average diameter of approximately 12 nm and length of 25 nm. The gas-sensing results demonstrated that the α-Fe2O3–ZnO heterostructure-based sensor exhibited excellent sensitivity, selectivity, and stability toward low-concentration NO2 gas at an optimal temperature of 300 °C. The α-Fe2O3–ZnO sensor, in particular, demonstrated substantially higher sensitivity compared with pristine α-Fe2O3, along with faster response and recovery speeds under similar test conditions. An appropriate material synergic effect accounts for the considerable enhancement in the NO2 gas-sensing performance of the α-Fe2O3–ZnO heterostructures.
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