2D SnO2/g-C3N4 Heterojunctional Nanocomposite-Based Acetone Sensor

In this study, a novel 2D SnO2/g-C3N4 nanosheet heterojunction was successfully synthesized utilizing a facile hydrothermal method coupled with a subsequent pyrolysis process. Comprehensive characterization employing X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA) confirmed the formation of nanocomposites featuring lamellar g-C3N4 nanosheets enveloping SnO2 nanoparticles. The SnO2/g-C3N4 heterojunctional composite, with a g-C3N4 weight of 55.66%, exhibited a remarkable maximum gas-sensing response of 8.81 towards 20 ppm acetone at the optimized operating temperature of 280 °C. This response was approximately 3.1 times higher than that observed for pure SnO2 nanoparticles. The heightened sensing performance is attributed to the homogeneous dispersion of SnO2 nanoparticles on lamellar g-C3N4 nanosheets and the formation of an n-n heterojunction. The insights gained from this investigation offer valuable implications for the design and fabrication of metal oxide-based heterojunctional nano/microstructures, providing enhanced capabilities for gas sensing applications.