EPR study of paramagnetic centers in SiO.sub.2./sub.:C:Zn nanocomposites obtained by infiltration of fumed silica with luminescent Zn(acac).sub.2./sub. solution

0543889 - FZÚ 2022 RIV UA eng J - Journal Article
Savchenko, Dariia - Memon, V.S. - Vasin, A.V. - Kysil, D. - Rusavsky, A.V. - Kuz, O.P. - Gareeva, F.M. - Kalabukhova, E.N.
EPR study of paramagnetic centers in SiO₂:C:Zn nanocomposites obtained by infiltration of fumed silica with luminescent Zn(acac)₂ solution.
Semiconductor Physics Quantum Electronics & Optoelectronics. Roč. 24, č. 2 (2021), s. 124-130. ISSN 1560-8034. E-ISSN 1605-6582
R&D Projects: GA MŠMT(CZ) EF16_019/0000760
Grant - others:OP VVV - SOLID21(XE) CZ.02.1.01/0.0/0.0/16_019/0000760
Institutional support: RVO:68378271
Keywords : silica-carbon nanocomposites * carbon-related centers * dangling bonds * exchange interaction * electron paramagnetic resonance
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Method of publishing: Open access

Silica-carbon with zinc (SiO2:C:Zn) nanocomposites obtained via infiltration with aged luminescent zinc acetylacetonate (Zn(acac)2) ethanol solution of two concentrations (1 or 4%) into the fumed silica (SiO2) matrix have been studied using EPR within the temperature range 6…296 K before and after thermal annealing. The EPR spectrum of SiO2:C:Zn nanocomposites consists of three signals with the Lorentzian lineshape corresponding to paramagnetic centers with S = 1/2, which are related to carbon dangling bonds (CDB) (g = 2.0029(3)), silicon dangling bonds (g = 2.0062(3)) and oxygen-centered carbon-related radicals (CRR) (g = 2.0042(3)). A small EPR linewidth (<1 mT) observed for CDB and oxygen-centered CRR allows us to conclude that they are in the sp3-hybridized state.
Permanent Link: http://hdl.handle.net/11104/0321002