Flexible hybrid nanostructured chemiresistive sensing platform for low-temperature trace hydrogen detection

Abstract

The prevalence of hydrogen (H2) utilization across commercial and industrial sectors has spurred the innovation of various H2 gas sensors. However, their practical implementation has been hindered by issues such as cost inefficiency, low sensitivity, inadequate selectivity, and limitations in low-temperature sensing capabilities. Consequently, the development of a sensor capable of surmounting these challenges is paramount for widespread adoption. In this study, a cost-effective approach has been used to fabricate a flexible hybrid nanostructured platform on polyethylene terephthalate (PET) substrate incorporating a combination of zinc oxide (ZnO), titanium oxide (TiO2), and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS). This platform has undergone meticulous morphological characterization and comprehensive evaluation for H2 gas sensing applications at both room temperature and 50˚C. The results reveal that the developed PEDOT:PSS/TiO2/ZnO NWs sensor exhibits superior H2 gas sensing characteristics with 141 % and 163 % higher response by proportions at 100 ppb and 100 ppm, respectively outperforming other prepared devices in the same environment. Thus demonstrating exceptional sensitivity of 0.448 %/ppm with three cycle repeatability, H2 selectivity and nine months of stability at low temperatures. Moreover, the sensor has an ultralow limit of detection (LOD) of ∼9 ppt, along with a rapid response time of 65 s and a recovery time of 42 s at an H2 concentration of 100 ppb. This research drives the advancement of efficient, rapid-responsive, and discerning trace detection of H2 gas at low temperatures.