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Enhanced Sub-ppm NH3 Gas Sensing Performance of PANI/TiO2 Nanocomposites at Room Temperature.

ABSTRACT: PANI/TiO2 nanocomposites spheres were synthesized using a simple and efficient one-step hydrothermal process. The morphology and structure of PANI/TiO2 nanocomposites spheres were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) techniques. The PANI/TiO2 nanocomposite sphere-based sensor exhibits good selectivity, sensitivity (5.4 to 100 ppm), repeatability, long-term stability and low detection limit (0.5 ppm) to ammonia at room temperature (20 ± 5°C). It also shows a good linearity relationship in the range of 0.5-5 and 5-100 ppm. The excellent NH3 sensing performance is mainly due to the formation of the p-n heterostructure in the nanocomposites.

SUBMITTER: Zhu C

PROVIDER: S-EPMC6201155 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Enhanced Sub-ppm NH3 Gas Sensing Performance of PANI/TiO2 Nanocomposites at Room Temperature.

Zhu Chonghui C Cheng Xiaoli X Dong Xin X Xu Ying Ming YM

Frontiers in chemistry 20181018

PANI/TiO2 nanocomposites spheres were synthesized using a simple and efficient one-step hydrothermal process. The morphology and structure of PANI/TiO2 nanocomposites spheres were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) techniques. The PANI/TiO2 nanocomposite sphere-based sensor exhibits good selectivity, sensitivity (5.4 to 100 ppm), repeatability, long-term stability and low detecti ...[more]

PMID: 30406078

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