Belt-like In2O3 based sensor for methane detection: Influence of morphological, surface defects and textural behavior

Herein, gas sensors based on mesoporous belt-like In2O3 products derived from a single-step electrospinning method were produced, and the influence of the annealing temperature on their sensing performance was evaluated. A detailed comparison of the morphology, surface defects and textural behavior of the belt-like In2O3 products was carried out to understand the observed gas sensing trends. The In2O3 sensor produced at an annealing temperature of 550 degrees C displayed improved sensing capabilities with a response of 1.1 to 90 ppm of methane at a lower operating temperature of 100 degrees C. The response and recovery times of this sensor were only 36 and 44 s, respectively, and it displayed good stability and selectivity as well as a lower detection limit of 0.18 ppm. Experimental characterization revealed that this enhanced sensing behavior originate from the mesoporous nature of belt-like In2O3 products composed of small-sized particles which offered a large number of active sites for methane gas molecules as a result of the high surface area and high concentration of oxygen vacancies, which enabled greater channels for methane gas adsorption and desorption capacity.

Automated summary

Gas sensors based on mesoporous belt-like In2O3 products derived from a single-step electrospinning method were prepared and their sensing performance was evaluated. The sensor annealed at 550 degrees C showed improved sensing capabilities, with a high response rate and short response and recovery times for methane at a lower operating temperature, as well as good stability, selectivity, and a low detection limit. The enhanced sensing behavior was attributed to the mesoporous structure, small particle size, high surface area, and high concentration of oxygen vacancies in the belt-like In2O3 products.