Fig. 2: SEM images of the WO3 (H2O)0.33 nanoneedles.
a The WO3 (H2O)0.33 nanoneedles before annealing at 300 °C for 2 h in air. b The WO3 (H2O)0.33 nanoneedles after annealing at 300 °C for 2 h in air.
Fig. 2: SEM images of the WO3 (H2O)0.33 nanoneedles. | NPG Asia Materials
