Preparation, characterisation and electrochromic property of mesostructured tungsten oxide films via a surfactant templated sol–gel process from tungstic acid

Abstract

Preparation, characterisation and electrochromic property of mesostructured tungsten oxide films via a surfactant templated sol-gel process from tungstic acid

Nanostructured Tungsten Oxide – Properties, Synthesis, and Applications

“…These nanostructured WO 3 ‐based devices show significant improvement in charge density,15, 30–33, 175, 178 coloration efficiency,174, 176 and coloration/bleach time32, 175, 176 compared to bulk amorphous and crystalline WO 3 . More importantly, it is observed that nanostructured hexagonal WO 3 ‐based devices have superior charge densities when compared to triclinic, monoclinic, and orthorhombic WO 3 9.…”

Dual‐Functional Surfactant‐Templated Strategy for Synthesis of an In Situ N2‐Intercalated Mesoporous WO3 Photoanode for Efficient Visible‐Light‐Driven Water Oxidation

“…[44][45][46][47] We recently reported as urfactant-templated approachf or ac rystalline, small-mesoporous WO 3 photoanode;i tp rovided al arge surfacea rea to increase the number of water-oxidation sites on the WO 3 surfacea nd shorter carrier-diffusionl ength in the nanosized pore walls for highly efficient PEC water oxidation. [9] To date, the surfactant-templated strategy for porous WO 3 has been restricted to the primaryr ole of structure direction of different ionic, [48][49][50] nonionic, [51,52] and block-copolymer [53][54][55] surfactants. Even for nanomaterials in general,amultifunctional role of at emplate has not been reported, except for afew chiral and luminescentnanomaterials.…”

Crystallization of Tungsten Trioxide Having Small Mesopores: Highly Efficient Photoanode for Visible‐Light‐Driven Water Oxidation

“…[10,12,13] In surfactant-templated mesoporous systems (> 5 nm pores), [22,23] thermal crystallization was attributively reported for TiO 2 [24][25][26] and was rarely described for other semiconductors. [27,28] Regarding mesoporous WO 3 , most of the studies are associated with either amorphous or poorly crystallized frameworks, [29][30][31][32] except for the high-temperature crystallization of a system having large mesopores (> 10 nm), reported by Smarsly and co-workers. [28] High-temperature crystallization was also demonstrated by providing amorphous carbon support inside mesopores (about 5-10 nm) for block-copolymer-templated TiO 2 [26] and Nb-Ta-mixed oxide, [27] which involve either strong acidic conditions [26] or multistep polymerization processes.…”

“…Considering the high density of crystalline WO 3 (7.16 g cm À3 ), the BET surface area of our WO 3 having small mesopores is comparable with ordered mesoporous silica [33,34] and to the best of our knowledge about two times higher compared to any other mesoporous WO 3 material reported so far. [28][29][30][31][32] Raman spectra ( Figure S4) of mesoporous WO 3 crystallized at 550 8C in N 2 exhibits two broad bands for amorphous carbon [36] around 1365 and 1590 cm À1 which completely disappeared after calcination in O 2 . Thermogravimetric (TG) analysis started with the amorphous WO 3 /PAL2-16 composite ( Figure S5) shows almost 16 and 32 % weight loss in N 2 and air, respectively, at 550 8C.…”