Synthesis of binary Co–Mg–O oxide system and study of its behavior in reduction/oxidation cycling
| Parent link: | International Journal of Hydrogen Energy Vol. 44, iss. 37.— 2019.— [P. 20690-20699] |
|---|---|
| Corporate Author: | |
| Other Authors: | , , , , , |
| Summary: | Title screen The nanoscale Co-Mg-O oxide sample (15 wt% in terms of Co3O4) was prepared from the corresponding xerogel synthesized by the modified sol-gel method. The hydrolysis of as-prepared Mg(OCH3)2 was carried out using the aqueous solution of Co(NO3)2 precursor. The CoOx nanocrystallites of about 10-20 nm in size were shown to be uniformly distributed within the MgO matrix. The reduction of Co-Mg-O in H2 flow was found to proceed in two separate stages within the temperature ranges of 200-350 °C and 350-600 °C. The prepared binary Co-Mg-O system was demonstrated to possess completely reproducible reduction behavior in the consecutive reduction/reoxidation cycles. The phase composition of the sample exposed to both the reducing and oxidative environment was followed by an in situ X-ray diffraction analysis performed at temperatures of 25, 300, 500 and 700 °C. The determined lattice parameters for MgO (a = 4.219 Å) and Co3O4 (a = 8.110 Å) were found to be slightly increased as compared with the values from Powder Diffraction File, so that the formation of joint non-stoichiometric (Mg1-xCox)O and (Co3-xMgx)O4 phases was suggested. The strong chemical interaction of cobalt oxide with MgO matrix was also evidenced by the data of a diffuse reflectance UV-vis spectroscopy. Режим доступа: по договору с организацией-держателем ресурса |
| Published: |
2019
|
| Subjects: | |
| Online Access: | https://doi.org/10.1016/j.ijhydene.2018.05.044 |
| Format: | Electronic Book Chapter |
| KOHA link: | https://koha.lib.tpu.ru/cgi-bin/koha/opac-detail.pl?biblionumber=661245 |