High performance ammonia gas sensor based on electrospinned Co3O4 nanofibers decorated with hydrothermally synthesized MoTe2 nanoparticles

Abstract

This paper introduces a room temperature NH3 gas sensor with excellent performance based on cobalt trioxide and molybdenum telluride (Co3O4-MoTe2) nanocomposite. Co3O4 nanofiber was synthesized by electrospinning, and MoTe2 nano particle was synthesized by simple hydrothermal method. MoTe2, Co3O4 and Co3O4-MoTe2 film sensors were prepared on interdigital electrode substrate by drop coating method. X-ray photoelectron spectroscopy (XPS), dispersive spectrometer (EDS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) were used to observe the morphology, microstructure, and composition of the prepared nano-materials. The gas sensing performance of the pristine Co3O4, MoTe2 and Co3O4-MoTe2 composite film sensors were tested at room temperature. The results of experimental research show that the Co3O4-MoTe2 gas sensor has better sensing performance for ammonia than the pure sensor, such as high response (56.20%@1ppm), excellent selectivity, good stability, short response/recovery time (7s/7s@1ppm) and low detection limit (26 ppb). The performance enhancement of the Co3O4-MoTe2 film sensor was mainly attributed to the p-n heterojunction formed between MoTe2 and Co3O4.