Effect of cation intercalation on the growth of hexagonal WO₃nanorods

The growth mechanism of hexagonal tungsten oxide (h-WO₃) nanorods is investigated using molecular dynamics simulation. The results show that cation intercalation has a great impact on the formation of h-WO₃nanorods, reflected from the attractive interaction between the growth species (polytungstate anion, W10O32â´Ã‚¯) and crystal faces of (001) and (100). In particular, an appropriate amount of intercalated cations not only accelerate the crystal growth but also induce the formation of one-dimensional nanostructure of h-WO₃ nanorods along the direction of [001]. An excess of intercalated cations would be unfavorable to the evolution of rod shape. Ammonium ion (NHâ‚„âº) is found to be the most stable in a hexagonal tunnel, hence being effective in inducing the 1D morphology of h-WO₃. The main findings from the simulations are also verified by experiments.