High-Pressure Synthesis of Cubic ZnO and Its Solid Solutions with MgO Doped with Li, Na, and K

Nikolai O Taibarei; Vladimir G Kytin; Elizaveta A Konstantinova; Vladimir A Kulbachinskii; Serguei V Savilov; Vladimir A Mukhanov; Vladimir L Solozhenko; Vadim V Brazhkin; Andrei N Baranov

doi:10.3390/ma16155341

High-Pressure Synthesis of Cubic ZnO and Its Solid Solutions with MgO Doped with Li, Na, and K

Materials (Basel). 2023 Jul 29;16(15):5341. doi: 10.3390/ma16155341.

Authors

Nikolai O Taibarei¹, Vladimir G Kytin², Elizaveta A Konstantinova², Vladimir A Kulbachinskii², Serguei V Savilov¹, Vladimir A Mukhanov¹, Vladimir L Solozhenko³, Vadim V Brazhkin⁴, Andrei N Baranov¹

Affiliations

¹ Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow, Russia.
² Department of Physics, Lomonosov Moscow State University, 119991 Moscow, Russia.
³ LSPM-CNRS, Université Sorbonne Paris Nord, 93430 Villetaneuse, France.
⁴ Institute for High Pressure Physics, Russian Academy of Sciences, Troitsk, 108840 Moscow, Russia.

Abstract

The possibility of doping ZnO in its metastable rock salt structure with Li, Na, and K intended to act as acceptor dopants was investigated. For the first time, Mg_xZn_1-xO alloys and pure ZnO with a rock salt structure doped with Li, Na, and K metals was obtained by high-pressure synthesis from pure oxides with the addition of carbonates or acetates of the corresponding metals as dopant sources. Successful stabilization of the metastable rock salt structure and phase purity were confirmed by X-ray diffraction. Transmission electron microscopy was used to study the particle size of nanocrystalline precursors, while the presence of Li, Na, and K metals in rock salt ZnO was detected by electron energy-loss spectroscopy and X-ray photoelectron spectroscopy in Mg_xZn_1-xO alloys. Electron paramagnetic resonance measurements revealed the acceptor behavior of Li, Na, and K dopants based on the influence of the latter on native defects and natural impurities in ZnO-MgO alloys. In addition, diffuse reflectance spectroscopy was used to derive band gaps of quenched rock salt ZnO and its alloys with MgO.

Keywords: doping; group I metals; high pressure; magnesium oxide; rock-salt structure; zinc oxide.

Grants and funding

This research was funded by Russian Ministry of Science and Higher Education, Federal Assignment Nos. AAAA-A21-121011990019-4 and Federal Assignment Nos. AAAA-A21-121011590082-2.