WO₃ films are the most widely used electrochromic functional layers. It is known that WO₃ films prepared by pure chemical method generally possess novel nanostructures, but the adhesion between WO₃ films and substrates is weak. However, WO₃ films prepared by pure physical method usually show relatively dense morphology, which limits their electrochromic properties. In order to break through these bottlenecks and further improve their electrochromic properties, this work first prepared nanostructured WO₃ powder by chemical method, and then using this powder as the evaporation source, nanostructured WO₃ films were fabricated by vacuum thermal evaporation method. Properties of nanostructured WO₃ films were systematically compared with those of ordinary WO₃ films. It turned out that the nanostructured WO₃ film exhibited better cyclic stability and memory effect, and also the optical modulation rate was 14% higher than that of the ordinary WO₃ film. More importantly, the nanostructured WO₃ film showed better adhesion with the ITO substrates. These results demonstrate that a combination of chemical and physical methods is an effective preparation method to improve the electrochromic properties of WO₃ films.

The monoclinic and hexagonal gallium tellurides (m-GaTe and h-GaTe) show different applications in optoelectronic devices. Compared to the m-GaTe, the h-GaTe is a metastable phase, which generally exists in ultrathin samples and is difficult to obtain by direct chemical reaction. Herein, a hexagonal ZnO-induced crystal growth strategy was used for the design and fabrication of h-GaTe. The high-quality h-GaTe nanosheets were successfully grown on the (001) surface of hexagonal ZnO by the chemical vapor deposition method under ambient pressure. The SEM, XPS, XRD, and HRTEM characterizations uncovered a flower-like nanosheet morphology and a hexagonal crystal structure for the obtained GaTe samples. Meanwhile, the conductive atomic force microscope measurement indicates that the obtained h-GaTe nanosheet is a p-type semiconductor. Based on the electron localization function simulation, the lattice-induced crystal growth of h-GaTe was demonstrated. The results give an insight into the synthesis of metastable phase crystal and open an avenue for fabricating new two-dimensional devices by p-type h-GaTe.