Властивості Zn-Мо-оксидної системи, синтезованої шляхом механохімічної обробки

• Datum: 2016
• Hauptverfasser: Sachuk, O. V., Zazhygalov, V. O., Kuznetsova, L. S., Tsyba, M. M.
• Format: Artikel
• Sprache: Ukrainisch
• Veröffentlicht: Chuiko Institute of Surface Chemistry National Academy of Sciences of Ukraine 2016
• Schlagworte: механохімічна обробка; цинк-молібденова композиція; молібдат цинку
• Online Zugang: https://www.cpts.com.ua/index.php/cpts/article/view/389
• Назва журналу: Chemistry, Physics and Technology of Surface

The mechanochemical treatment of ZnO-MoO3 mixtures with different molar ration of the oxides (15/85, 25/75, 50/50 and 75/25) has been studied. The treatment was realized at 550 rpm, BPR = 10 (sample mass was equal to 10 g) and variation of treatment time (2, 4 and 8 h). The properties of the obtained samples were investigated by means of XRD, IR, DTA, BET, SEM methods. It was shown that for all the compositions after 2 h of treatment the decrease of XRD reflexes intensity of initial oxides and their broadening were observed. This fact can be connected with a decrease of oxides particles size which was confirmed by calculation and SEM data. An increase of treatment time for the mixtures with ZnO/MoO3 = 15/85 and 75/25 was accompanied by subsequent decrease of reflexes intensity and the most intense reflexes of MoO3 and ZnO, respectively, were fixed in these compositions only. In the case of the ZnO/MoO3 = 25/75 and 50/50 mixtures the increase of treatment time up to 4 h leads to an appearance of new reflexes which can characterized the formation of MoO3·0.5H2O and ZnMoO4 phases. The IR-spectra confirm the change of phase composition of these mixtures and SEM data show the changes of the crystallites habitus. After 8 h treatment, the future changes in the composition of these mixtures were observed. Treatment of ZnO/MoO3 = 25/75 was accompanied by little increase of both phases reflexes intensity but in the case of ZnO/MoO3 = 50/50 the reflexes of ZnMoO4phase were fixed only. The DTA data confirm the changes of these mixtures composition provoked by mechanochemical treatment. BET data show that treatment of ZnO/MoO3 = 50/50 leads to the increase in specific surface area of the sample from 2 up to 9 m2/g and to the appearance of micro- and mesopores in solid (initial mixture was a non-porous composition). So, the chemical reaction between ZnO and MoO3 initiated by mechanochemical treatment with formation of new ZnMoO4 phase with bi-porous structure was found.