Ultra-Sensitive Photo-Induced Hydrogen Gas Sensor Based on Two-Dimensional CeO-Pd-PDA/rGO Heterojunction Nanocomposite.

A two-dimensional (2D) CeO-Pd-PDA/rGO heterojunction nanocomposite has been synthesised via an environmentally friendly, energy efficient, and facile wet chemical procedure and examined for hydrogen (H) gas sensing application for the first time. The H gas sensing performance of the developed conductometric sensor has been extensively investigated under different operational conditions, including working temperature up to 200 °C, UV illumination, H concentrations from 50-6000 ppm, and relative humidity up to 30% RH. The developed ceria-based nanocomposite sensor was functional at a relatively low working temperature (100 °C), and its sensing properties were improved under UV illumination (365 nm).