Langmuir-Blodgett self organized nanocrystalline tungsten oxide thin films for electrochromic performanceElectronic supplementary information (ESI) available. See DOI: 10.1039/c5ra00208g

We explore a novel method to synthesize pebble-like nanocrystalline WO 3 thin films for the first time by thermal decomposition of a multilayer Langmuir-Blodgett film of an octadecylamine-tungsten complex. The resulting film was thoroughly characterized by various characterization techniques. The electrochromic performance was evaluated in Li + as a charge-balancing ion. The WO 3 thin film displays a state-of-the-art performance with respect to optical modulation of 25.94% at λ 630 nm with a very rapid coloration and bleaching time of 3.57 s and 3.14 s, respectively and a high coloration efficiency of 71.26 cm 2 C −1 . The excellent electrochromic performance can be attributed to the high size uniformity of WO 3 nanoparticles, whose crystalline nature offer more active sites for Li + diffusion and control the diffusion path length. Thus, the Langmuir-Blodgett WO 3 film contributes to high energy conversion devices. Langmuir-Blodgett self organized nanocrystalline tungsten oxide thin films.