- Preparative inorganic chemistry: development of innovative methods for synthesis of inorganic salts, oxides, solid solutions and composites;
- Crystal chemistry of inorganic compounds;
- Vibrational Spectroscopy (infrared and Raman spectroscopy): interpretation of vibrational spectra; factor group analysis; matrix spectroscopy; bonding interactions in solid state;
- Synthesis, structure, spectroscopic and morphological characterization of polyanion intercalation materials as electrodes for lithium-ion and post lithium-ion batteries;
- Thermal analysis.
- V. Koleva, T. Boyadzieva, R. Stoyanova,
“Crystal and Morphology Design of Dittmarite-Type Ammonium Iron–Manganese Phosphates, NH4Mn1–xFexPO4·H2O, as Precursors for Phospho-olivine Electrodes“,
Crystal Growth and Design 19 (2019) 3744-3754.
- R. Stoyanova, V. Koleva, A. Stoyanova,
“Lithium versus Mono/Polyvalent Ion Intercalation: Hybrid Metal Ion Systems for Energy Storage”,
The Chemical Record 19 (2019) 474-501.
- L. Mihaylov, T. Boyadzhieva, R. Tomov, V. Kumar, V. Koleva, R. Stoyanova, T. Spassov,
“LiMnPO4-olivine deposited on a nanoporous alloy as an additive-free electrode for lithium ion batteries”,
Dalton Transactions 48 (2019) 17037-17044.
- T. Boyadzieva, V. Koleva, R. Stoyanova,
“Crystal chemistry of Mg substitution in NaMnPO4 olivine: concentration limit and cation distribution”,
Physical Chemistry Chemical Physics 19 (2017) 12730-12739.
- T. Boyadzhieva, V. Koleva, E. Zhecheva, D. Nihtianova, L. Mihaylov, R. Stoyanova,
“Competitive Lithium and Sodium Intercalation into Sodium Manganese Phospho-Olivine NaMnPO4 Covered with Carbon Black”,
RSC Advances 5 (2015) 87694-87705.