Mayuri Ausekar, Ravi Mawale, Pavel Pazdera, JosefHavel

The WO3 is multifunctional material and has unique characteristics. It has wide range of applications in biomedicine, cosmetics, electronics, coatings and plastics, catalysis, etc. [1-2]. It has been studied for its various properties such as electrochromism, photocatalysis, and/or sensing capabilities, for example [3]. In this work Laser Desorption Ionisation (LDI) with QIT-TOF-MS was used to study the generation of WO3 clusters in gas phase and the formation of (WO3)n+/- (n=1-7) was detected (Fig. 1). When nanodiamonds and graphene oxide were used as matrices, the spectra in positive ion mode were found more complex than in negative one and higher (WO3)n- (n=1-19) clusters were detected. In addition to (WO3)n- clusters also some oxygen rich and/or oxygen defficient species were found in both LDI and MALDI methods. The total number of clusters identified was over one hundred. Concluding, the use of carbonaceous matrices enabled observation of high mass (WO3)n- clusters (n up to 19) for the first time. The knowledge of generation of high mass tungsten oxide clusters in gas phase and clusters stoichiometry can be useful to develope new materials.