Diana Georgieva Kichukova

Dr. Diana Georgieva Kichukova

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Research Focus & Metrics

Academic Career Length

5Years (2022-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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17 June 2022 in Nanomaterials
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DKDiana Georgieva Kichukova
Diana Georgieva Kichukova
Ivanka SpassovaIvanka Spassova
Ivanka Spassova
AKAneliya Kostadinova
Aneliya Kostadinova
ASAnna Staneva
Anna Staneva
Daniela KovachevaDaniela Kovacheva
Daniela Kovacheva
In the present study, we report on the facile prepared nanocomposites of reduced graphene oxide RGO with Cu and Ag. The synthesis was performed through an environmentally friendly and easy method by simultaneous reduction in solutions containing Cu2+ or Ag+ and graphene oxide (GO) using zinc powder as a reducing agent in aqueous acidic media. The composites are characterized by powder X-ray diffraction, low-temperature nitrogen adsorption, X-ray photoelectron and FTIR and Raman spectroscopies, as well as Scanning and Transmission electron microscopies. The antibacterial activity of the composites was tested for Staphylococcus aureus, Escherichia coli and antifungal activity for Candida albicans. The cytotoxicity of the materials was studied towards two types of eukaryotic cells—MDCK II and A549 cell lines. The composites obtained consist of homogeneously distributed Cu and Ag nanoparticles on the surface of graphene sheets and manifest good antimicrobial activity and high cytotoxicity. The results clearly show that both metal–RGO composites can be successfully used as antimicrobial and anticancer agents.

22 August 2023 in Materials
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PVPaunka Vassileva
Paunka Vassileva
VTVencislav Tumbalev
Vencislav Tumbalev
DKDiana Georgieva Kichukova
Diana Georgieva Kichukova
DVDimitrinka Voykova
Dimitrinka Voykova
Daniela KovachevaDaniela Kovacheva
Daniela Kovacheva
Ivanka SpassovaIvanka Spassova
Ivanka Spassova
In the current investigation, the removal efficiency regarding a cationic dye, methylene blue (MB), from three graphene-based materials was investigated. The materials’ characterization process involved instrumental methods such as XRD, XPS, SEM, TEM, FTIR, and nitrogen adsorption at 77 K. The survey examined how various process factors influenced the ability of the studied materials to adsorb cationic dyes. These parameters encompassed contact time, initial dye concentrations, solution pH, and temperature. The adsorption procedure was effectively explained through the application of pseudo-second-order and Langmuir models. The maximum adsorption capacity for the best adsorbent at 293 K was found to be 49.4 mg g−1. In addition, the study also determined the entropy, enthalpy, and Gibbs free energy values associated with the removal of MB and showed that the adsorption of MB is endothermic, feasible, and spontaneous. The results also revealed that the studied materials are suitable adsorbents for the removal of cationic dyes.

20 August 2023 in Catalysts
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Ralitsa VelinovaRalitsa Velinova
Ralitsa Velinova
Anton NaydenovAnton Naydenov
Anton Naydenov
DKDiana Georgieva Kichukova
Diana Georgieva Kichukova
VTVentsislav Tumbalev
Ventsislav Tumbalev
GAGenoveva Atanasova
Genoveva Atanasova
Ivanka SpassovaIvanka Spassova
Ivanka Spassova
The work presents Pd-containing catalysts for practical application with enhanced low-temperature activity in the complete oxidation of volatile organic compounds (VOCs) using innovative combinations of reduced graphene oxide (RGO) and alumina. The catalysts were characterized by XRD, SEM, TEM, XPS, low-temperature N2-adsorption, and CO chemisorption. The tests on complete catalytic oxidation of different VOC (propane, butane, hexane, dimethyl ether, toluene, propylene) and CO were carried out. The reaction kinetics and the mechanism of the reaction of complete oxidation of toluene are being investigated in detail. The results show that the new catalyst design makes it able to completely oxidize the studied VOCs and CO at low temperatures (100–350 °C) with long-term stability. Using a variety of instrumental methods, it was established that for high activity and long-term stability, the optimal ratio Pd/PdO should be close to 1:1. The most probable mechanism of complete toluene oxidation is the mechanism of Langmuir–Hinshelwood. The high activity and the weak effect of water on the catalyst performance leads to further perspectives for the application of the currently developed approach for the preparation of large-scale monolithic catalytic systems for air pollution control.