Room-temperature ethanol sensors based on amorphous Ta2O5/Pd hybrid microspheres

Abstract

Ta2O5/Pd hybrid microspheres were readily synthesized via a one-step thermal solution process employing a template composed of glucose carbon spheres, yielding a structure characterized by a rough and porous surface. This morphology offers an expanded contact area and increased sites for ethanol reactions of Ta2O5/Pd hybrid microspheres. At room temperature (25 °C), the Ta2O5/Pd hybrid microspheres exhibited responsiveness to ethanol concentrations ranging from 50 to 700 ppm, displaying a linear response pattern to a narrow concentration gradient of 90–120 ppm. The hybrid exhibited notable sensitivity, manifesting a response value of 5.1–100 ppm ethanol. In addition, they displayed less responsiveness to other VOCs gases, were minimally affected by humidity, and maintained gas-sensitive stability for 30 days, demonstrating excellent selectivity and long-term stability. Based on the fitting curve analysis, the material theoretically demonstrated the ability to detect ethanol at concentrations as low as 101 ppb. Ta2O5/Pd hybrid microspheres modified by glucose carbon sphere templates and noble metal nanoparticles are promising candidates for ethanol room temperature sensing, providing new insights into the development of room temperature sensing.