Synthesis and Enhanced Ethanol Gas Sensing Properties of the g-C(3)N(4) Nanosheets-Decorated Tin Oxide Flower-Like Nanorods Composite

Flower-like SnO(2)/g-C(3)N(4) nanocomposites were synthesized via a facile hydrothermal method by using SnCl(4)·5H(2)O and urea as the precursor. The structure and morphology of the as-synthesized samples were characterized by using the X-ray powder diffraction (XRD), electron microscopy (FESEM and TEM), and Fourier transform infrared spectrometer (FT-IR) techniques. SnO(2) displays the unique 3D flower-like microstructure assembled with many uniform nanorods with the lengths and diameters of about 400–600 nm and 50–100 nm, respectively. For the SnO(2)/g-C(3)N(4) composites, SnO(2) flower-like nanorods were coupled by a lamellar structure 2D g-C(3)N(4). Gas sensing performance test results indicated that the response of the sensor based on 7 wt. % 2D g-C(3)N(4)-decorated SnO(2) composite to 500 ppm ethanol vapor was 150 at 340 °C, which was 3.5 times higher than that of the pure flower-like SnO(2) nanorods-based sensor. The gas sensing mechanism of the g-C(3)N(4)nanosheets-decorated SnO(2) flower-like nanorods was discussed in relation to the heterojunction structure between g-C(3)N(4) and SnO(2).