Structural study of a new hexagonal form of tungsten trioxide

On the origin of the spontaneous formation of nanocavities in hexagonal bronzes (W,V)O3

“…They could be assigned directly to the hexagonal phase NaxWO3+x/2.zH2O, 17 P63/mcm, a= 0.7298 nm, c= 0.7798 nm. 18 Octahedra tilting in the HTB-type compounds always seem to be observed and it has been previously reported as related to the doubled periodicity along c. 19,20 By rotating around their edges, the tilts of neighboring octahedra are equal but opposite, thus being the origin of the c parameter doubling although it does not modify the periodicity along a.…”

Enhanced photochemical performance of hexagonal WO3 by metal-assisted S–O coupling for solar-driven water splitting

“…The results of geometry optimization for pure h-WO 3 , monodoped and codoped systems are summarized in Table 1, where the calculated lattice parameters for the pure h-WO 3 are very close to the previous experimental and theoretical results [50,51]. For the doped systems, various degrees of lattice distortions are found and the incorporation of Pb leads to distinct lattice expansions due to the large ionic radius of Pb 4+ (Pb…”

X-ray study and structure simulation of amorphous tungsten oxide

“…The coordination polyhedron of the hexagonal WO 3 modi®cation is also an octahedron (Gerand et al, 1979), and the WO 6 octahedra not only share their vertices but also form a structural pattern different from that characteristic of the ReO 3 phases (Fig. 3c).…”

“…These are cubic (Palatnic et al, 1973), tetragonal, monoclinic and triclinic (Udalova & Klechkovskaya, 1986) modi®cations. In addition to these modi®cations, we have a hexagonal WO 3 phase, ®rst synthesized by dehydration of WO 3 (1/3)H 2 O (Gerand et al, 1979). Later, hexagonal crystals of this phase were also obtained in the synthesis of anodic oxide ®lms (Falaras et al, 1984).…”