Synthesis of single-crystalline potassium-doped tungsten oxide nanosheets as high-sensitive gas sensors

The single-crystalline potassium-doped tungsten oxide nanosheets were prepared by simply heating a treated foil of tungsten. The as-prepared products were characterized using X-ray powder diffraction (XRD), scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, and selected-area electron diffraction (SAED). XRD and SAED results revealed that the products are pure, single-crystalline. The nanosheets width reaches to 30 μm and thickness is about 80 nm. The nanosheets have high sensitivity, fast response time and good stability to H2S, acetone and other gases.