Controlled synthesis of manganese tungstate nanorods for highly selective NH3 gas sensor

Highlights: • MnWO₄ nanorods were controllably synthesized by an effective method. • MnWO₄ nanorods exhibited single-crystallite after heated treatment. • Gas sensor based on MnWO4 showed higher performance to NH₃ gas. In this paper, single-crystalline MnWO₄ nanorods were prepared through a facile single-step hydrothermal approach and used for gas sensing. The morphology and phase of the products were characterized in detail through transmission electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, and elemental dispersive spectrum analyses. Results showed that the as-prepared MnWO₄ nanorods possess uniform shape with their length of 250–300 nm and width of 20–30 nm. The nanorods were used to fabricate sensors for detecting reducing gases such as NH₃, H₂ and CO and evaluate gas sensing properties. The sensors exhibit not only good response and fast response time, but also almost full recovery and good stability, to NH₃ gas.