Hydrogen Sulfide Gas Detection Using Two-Dimensional Rhodonite Silicate

Hydrogen sulfide is a hazardous gas that is found in common industrial waste sources, including sewage and oil refineries; it is lethal at concentrations exceeding 100 ppm. Two-dimensional (2D) oxide materials with a high surface area and environmental stability can be utilized for ultralow concentration gas sensing (H2S gas). Here, we demonstrate the gas sensing properties of two-dimensional rhodonite silicate (R-silicate) extracted from natural mineral ore. 2D R-silicate shows high sensitivity of up to 0.2 ppm–1 and high selectivity toward H2S compared to CO2, ethanol, acetone, and ammonia. The sensors developed using 2D R-silicate are found to be stable after five months. The high surface area and composition consisting of Mn atoms play a significant role in the sensing behavior. Ab initio computing simulations explain the mechanism of the selectivity of H2S over CO2 using 2D R-silicate. The simulation also demonstrates the chemical interaction of H2S with the 2D surface of R-silicate, which is further supported by Raman spectroscopy. The findings of this study provide new opportunities for using environmentally stable natural silicate 2D materials as efficient replacements for conventional metal oxides for ultrasensitive sensors.