Article
Chemistry, Physical
Mengli Zhou, Yang Xu, Guangqian Luo, Qingzhu Zhang, Lin Du, Zehua Li
Summary: This study prepared Ce-Fe binary oxide modified bentonite for mercury removal from flue gas. The modified bentonite showed better removal performance and the removal mechanism was revealed. Furthermore, the deactivated modified bentonite can be effectively regenerated after thermal treatment.
APPLIED SURFACE SCIENCE
(2022)
Article
Chemistry, Applied
Lorena P. Rivoira, Veronica A. Valles, Maria L. Martinez, Yanika Sa-ngasaeng, Siriporn Jongpatiwut, Andrea R. Beltramone
Summary: The study focused on catalytic oxidation of sulfur compounds in liquid fuel using ceria and ceria-zirconium based mesoporous catalysts. Different synthesis methods and characterization techniques were employed to understand the catalyst properties. It was found that catalysts with zirconium promoter showed higher dispersion, smaller particle size, and isolated Zr4+ species when directly synthesized. This enhanced Lewis acidity and catalytic activity for sulfur compound oxidation.
Article
Chemistry, Physical
Sylwia Gorecka, Katerina Pacultova, Aneta Smykalova, Dagmar Fridrichova, Kamil Gorecki, Anna Rokicinska, Piotr Kustrowski, Radim Zebrak, Lucie Obalova
Summary: The study showed a high correlation between the amount of copper and the efficiency of the catalysts for selective catalytic oxidation of ammonia. Copper species in the form of highly dispersed CuO oxides were found to be responsible for high N-2 selectivity, while the addition of cerium had an effect on the material's catalytic activity and N-2 selectivity. The developed materials exhibited high catalytic activity in a wide range of concentrations of ammonia and oxygen.
APPLIED SURFACE SCIENCE
(2022)
Article
Energy & Fuels
Binghong Song, Caiting Li, Xueyu Du, Shanhong Li, Yindi Zhang, Yue Lyu, Qihao Zhou
Summary: Cu1Ce3 catalyst shows superior toluene oxidation activity with high selectivity and stability, making it promising for practical applications. The catalytic oxidation of toluene over Cu1Ce3 catalyst involves two main pathways through benzyl alcohol and benzoic acid.
Article
Nanoscience & Nanotechnology
Tanya Tsoncheva, Consolato Rosmini, Mihail Mihaylov, Jiri Henych, Kristina Chakarova, Nikolay Velinov, Daniela Kovacheva, Zuzana Nemeckova, Martin Kormunda, Radostina Ivanova, Ivanka Spassova, Konstantin Hadjiivanov
Summary: In this study, the effects of the Fe/Ce ratio and the calcination temperature of cerium-iron oxides on Nickel-decorated mesoporous cerium-iron oxide composites were investigated. The research delves into the complex role of the FeCe support in the reaction mechanism.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Engineering, Environmental
Gontzal Lezcano, Natalia Realpe, Shekhar R. Kulkarni, Salvador Sayas, Jose Cerrillo, Natalia Morlanes, Hend O. Mohamed, Vijay K. Velisoju, Ragad F. Aldilajan, Sai P. Katikaneni, Mohammad Rakib, Bandar Solami, Jorge Gascon, Pedro Castano
Summary: Ammonia decomposition is an attractive process for decarbonized hydrogen production. Alkalis are known to promote the reaction. This study evaluates the kinetic contribution of Ba as a promoter in Co-Ce catalysts and investigates its influence on the elementary steps of ammonia decomposition using a microkinetic approach.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Materials Science, Ceramics
Jichao Zhu, Lifang Hu, Jie He, Hongshan Cui
Summary: This study investigates the removal characteristics of ethyl mercaptan on hexaniobate nanotubes and metal-doped hexaniobate nanotubes. Results show that doping with Fe and Ce significantly improves the removal capacity and breakthrough adsorption capacity of ethyl mercaptan. The oxidative activity is enhanced by the co-doping of Fe and Ce, with potential for regeneration up to four times.
CERAMICS INTERNATIONAL
(2022)
Article
Chemistry, Multidisciplinary
Takuya Hasegawa, Naoki Yamasaki, Yusuke Asakura, Tadaharu Ueda, Shu Yin
Summary: Layered perovskites with fascinating chemical properties can be chemically modified to form nanosheets. By manipulating the perovskite layer itself, a charge-neutral perovskite layer was synthesized, demonstrating the potential for developing innovative functional materials. This new structural concept allows for systematic tuning of the electronic structure through redox control of Ce, leading to diverse features not found in conventional layered perovskites.
Article
Chemistry, Multidisciplinary
Jie Yang, Zuobei Wang, Ruonan Li, Xiaofeng Xu, Junrui Liu, You-Gui Huang, Xin Ye, Wei Wang
Summary: Excessive phosphorus in water is a global problem causing eutrophication. Adsorbents play a key role in treating phosphorus-containing wastewater. In this study, Ce/Fe adsorbents were synthesized and characterized. Ce/Fe(-)15/3, with a Ce loading of 28.33 wt% and Fe loading of 5.66 wt%, exhibited high P adsorption capacity and selectivity in different solutions. The adsorption behavior of Ce/Fe-15/3 was well described by the Langmuir and pseudo-second-order models.
Article
Materials Science, Multidisciplinary
Yi-Jie Lao, Xing-Xing Jiang, Ju Huang, Zhen Zhang, Xing-Yi Wang
Summary: The La/Ce(0.5)Mn(0.5) catalyst prepared by wetness impregnation showed high activity and stability in the catalytic oxidation of ethyl acetate, converting it into CO2 with high efficiency. The intermediates identified were mainly ethanol and acetaldehyde, with concentrations below certain levels. The dissociative adsorption modes of ethyl acetate on the catalyst surface were found to be related to the surface oxygen species, affecting the stability and selectivity of the catalyst.
Article
Chemistry, Physical
Liyan Wang, Tao Zhang, Jiaqian Yang, Nana Gong, Qingxiang Ma, Yingquan Wu, Yisheng Tan
Summary: The introduction of Ce promoter optimized the catalytic performance of ZnCr-based catalysts, promoting the formation of HCOO species, carbon chain growth, and C-C coupling activity, ultimately leading to the production of isobutanol.
Article
Engineering, Environmental
Hayat Khan, Mohamed Gar Alalm, Marc Lalonde-Lavoie, Marcela Frias Ordonez, Marta Sartirana, Alessia Giordana, Giuseppina Cerrato, Claudia L. Bianchi, Daria Camilla Boffito
Summary: Ce-doped TiO2 showed good performance in the photocatalytic degradation of NOx and ethanol under visible light. Ce0.8T catalyst exhibited the lowest bandgap and the highest degradation rate among all prepared catalysts.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2021)
Article
Chemistry, Applied
Lei Li, Liping Song, Zhaoyang Fei, Wei Chu, Xiaofeng Luo, Jinlong Yan
Summary: The effects of different support materials on the catalytic performance of toluene removal were investigated. The Mn-Ce binary oxides supported on ZrO2 showed the best catalytic activity, attributed to low-temperature reducibility and abundant surface species. XPS and TPR results revealed good interaction between Mn and Ce elements in MnCe/ZrO2, and weak interaction between metal oxide and support promoted the dispersion and reduction of MnCe oxides at low temperature.
JOURNAL OF RARE EARTHS
(2022)
Article
Chemistry, Physical
Yongdong Chen, Yue Li, Wei Chen, Wen Wu Xu, Zhong-kang Han, Ammara Waheed, Zhongbin Ye, Gao Li, Alfons Baiker
Summary: The study evaluated bismuth doped cerium oxide catalysts for continuous dimethyl carbonate (DMC) synthesis and found that bismuth incorporation facilitated controlling oxygen vacancy density, leading to increased DMC production rates. The highest DMC yield was obtained with the Bi0.12Ce0.88O delta catalyst, which showed stable activity over a 45-hour period. In-situ modulation excitation diffuse reflection Fourier transform infrared spectroscopy and first-principle calculations revealed that DMC synthesis occurs through reaction of a bidentate carbonate intermediate with activated methoxy species.
Article
Engineering, Environmental
Qian Wang, Can He, Yue Shan, Zhongguo Zhang, Jiuyi Li
Summary: The aim of this study was to investigate the degradation efficiency and mechanism of atenolol (ATL) using Al2O3 supported manganese-cerium mixed oxides (Mn-Ce@Al2O3) as a catalyst for catalytic ozonation. Mn-Ce@Al2O3 with 0.2 wt% manganese and 0.2 wt% cerium showed excellent catalytic performance, leading to complete ATL degradation and 63% mineralization. The catalyst had a high specific surface area due to the presence of Mn-Ce solid solution on the surface, which promoted the formation of oxygen vacancies and electron transfer. O-2(center dot-) and center dot OH were identified as the main active radicals for ATL degradation and mineralization.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2023)
Article
Nanoscience & Nanotechnology
Tanya Tsoncheva, Consolato Rosmini, Mihail Mihaylov, Jiri Henych, Kristina Chakarova, Nikolay Velinov, Daniela Kovacheva, Zuzana Nemeckova, Martin Kormunda, Radostina Ivanova, Ivanka Spassova, Konstantin Hadjiivanov
Summary: In this study, the effects of the Fe/Ce ratio and the calcination temperature of cerium-iron oxides on Nickel-decorated mesoporous cerium-iron oxide composites were investigated. The research delves into the complex role of the FeCe support in the reaction mechanism.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Materials Science, Characterization & Testing
Adam Verner, Jonas Tokarsky, Pavla Capkova, Petr Rysanek, Oldrich Benada, Jiri Henych, Jakub Tolasz, Martin Kormunda, Michal Syrovy
Summary: Layered crystal structures form flat platelet-like crystallites, and nanofibers with such structures exhibit strip-like morphology. In this study, PVDF nanofibers were prepared with strip-like morphology and longitudinal folding, and surface-modified with CeO2 nanoparticles. Molecular modeling showed that the dominant PVDF(100) plane is suitable for anchoring the CeO2 nanoparticles. Preferred crystallographic orientations of the anchored CeO2 nanoparticles were also revealed. This successful surface modification provides potential applications for the CeO2/PVDF membrane.
Article
Chemistry, Multidisciplinary
Pavel Janos, Jakub Ederer, Martin Stastny, Jakub Tolasz, Jiri Henych
Summary: This study used a simple and easily scalable wet procedure to prepare nanocrystalline cerium oxide capable of decomposing the organophosphate pesticide parathion methyl. The research revealed the influence of solvent systems on the degradation efficiency of cerium oxide, providing a theoretical basis for further studies on the degradation of organophosphate compounds.
ARABIAN JOURNAL OF CHEMISTRY
(2022)
Article
Chemistry, Physical
Consolato Rosmini, Tanya Tsoncheva, Daniela Kovatcheva, Nikolay Velinov, Hristo Kolev, Daniela Karashanova, Momtchil Dimitrov, Boyko Tsyntsarski, David Sebastian, Maria Jesus Lazaro
Summary: Ceria-iron oxide mesoporous materials were modified with Ni-Fe alloys and further transformed into ferrous carbides and metal alloys encapsulated within carbon nanofibers. The modified phases showed high electrochemical activity and low overpotential in the Oxygen Evolution Reaction. The morphological, textural and physicochemical properties of the samples were characterized in detail.
Article
Environmental Sciences
G. Issa, M. Dimitrov, S. P. Marinov, N. Velinov, I Spasova, D. Kovacheva, T. Tsoncheva
Summary: In this study, activated carbons were produced from waste biomass and plastic residues, and were used as a host matrix for iron and/or chromium oxide nanoparticles. The materials were thoroughly characterized using various physicochemical techniques, and it was found that the pore structure of the activated carbon plays a crucial role in the dispersion, phase composition, and catalytic behavior of the loaded metal oxide species.
WASTE AND BIOMASS VALORIZATION
(2023)
Article
Pharmacology & Pharmacy
Yordan Yordanov, Denitsa Stefanova, Ivanka Spassova, Daniela Kovacheva, Virginia Tzankova, Spiro Konstantinov, Krassimira Yoncheva
Summary: This study focused on the development of polymeric nanomicelles loaded with cannabidiol as a drug delivery system with neuroprotective effects. The results showed that loading cannabidiol into the nanomicelles reduced its cytotoxicity and provided stronger protection against oxidative stress. Interestingly, the empty nanomicelles also demonstrated a protective activity against oxidative stress.
Article
Crystallography
Martin Tsvetkov, Elzhana Encheva, Stefani Petrova, Ivanka Spassova, Maria Milanova
Summary: This study presents the synthesis of La1-xCexFeO3+x/2 orthoferrites (x = 0.00, 0.01, 0.03, 0.05, and 0.07) through a simple and effective mechanochemical transformation from constituent oxides. Physicochemical methods such as powder X-ray diffraction (XRD), transmission electron microscopy (TEM), UV-Vis spectroscopy, and BET adsorption were used to investigate the influence of Ce4+ content on the structural, textural, and optical properties of the samples. The catalytic activity of the samples for water decontamination was evaluated in a photo-Fenton-like activation of persulfate, which showed significantly enhanced removal efficiency under visible light illumination.
Article
Pharmacology & Pharmacy
Lyubomira Radeva, Yordan Yordanov, Ivanka Spassova, Daniela Kovacheva, Virginia Tzankova, Krassimira Yoncheva
Summary: This study aimed to improve the safety of the anticancer drug doxorubicin by encapsulating it with the cardioprotective agent resveratrol in Pluronic micelles. The micelles were successfully prepared and characterized by small size and narrow size distribution. In vitro studies showed that the dual-loaded micelles reduced the cytotoxicity of doxorubicin in cardiac cells while enhancing its cytotoxic effect in lymphoma cells.
Article
Biotechnology & Applied Microbiology
Christina Voycheva, Teodora Popova, Marta Slavkova, Virginia Tzankova, Denitsa Stefanova, Diana Tzankova, Ivanka Spassova, Daniela Kovacheva, Borislav Tzankov
Summary: This study aims to investigate the potential of carboxylated and non-carboxylated mesoporous silica nanoparticles for the double loading of doxorubicin hydrochloride and quercetin to reduce the cardiotoxicity of doxorubicin. The results showed successful double loading of doxorubicin and quercetin in the nanoparticles, and the carboxy-modified nanosystems demonstrated a decreased in vitro cardiotoxicity of doxorubicin.
BIOENGINEERING-BASEL
(2023)
Article
Pharmacology & Pharmacy
Borislav Tzankov, Christina Voycheva, Alexandra Tosheva, Denitsa Stefanova, Virginia Tzankova, Ivanka Spassova, Daniela Kovacheva, Kati Avramova, Diana Tzankova, Krassimira Yoncheva
Summary: This study discussed the use of two types of mesoporous silica particles incorporated in oleogel for sustained-release dermal delivery of quercetin. The biopharmaceutical evaluation showed improved water solubility of quercetin and controlled drug release after incorporation of the particles in oleogel. The drug loaded mesoporous silica nanosystems and the corresponded oleogels demonstrated excellent biocompatibility and lack of hypersensitivity of quercetin formulations.
JOURNAL OF DRUG DELIVERY SCIENCE AND TECHNOLOGY
(2023)
Article
Chemistry, Physical
Paunka Vassileva, Vencislav Tumbalev, Diana Kichukova, Dimitrinka Voykova, Daniela Kovacheva, Ivanka Spassova
Summary: This study investigated the removal efficiency of methylene blue (MB) using three graphene-based materials. The materials were characterized using various instrumental methods and the study examined how different process factors influenced the materials' ability to adsorb cationic dyes.
Article
Chemistry, Physical
Ralitsa Velinova, Anton Naydenov, Diana Kichukova, Ventsislav Tumbalev, Genoveva Atanasova, Daniela Kovacheva, Ivanka Spassova
Summary: This work presents Pd-containing catalysts for the complete oxidation of VOCs with enhanced low-temperature activity. The catalysts, composed of reduced graphene oxide (RGO) and alumina, show long-term stability and the ability to completely oxidize various VOCs and CO at low temperatures (100-350°C). The optimal Pd/PdO ratio for high activity and stability is found to be close to 1:1.
Article
Chemistry, Physical
D. Panayotov, V. Zdravkova, O. Lagunov, S. Andonova, I. Spassova, D. Nihtianova, G. Atanasova, N. Drenchev, E. Ivanova, M. Mihaylov, K. Hadjiivanov
Summary: In this study, the role of structural and textural characteristics of ceria and ceria-zirconia nanomaterials in controlling CO2 capture performance was investigated. Two commercial cerias and two home-prepared samples were studied, and their characteristics were analyzed by various techniques. The commercial ceria samples showed similar performance due to the formation of the same types of surface species. The synthesized CeO2 sample had a disadvantageous mass transfer zone, while the CeO2-ZrO2 oxide showed the highest CO2 capture capacity.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Jiri Henych, Martin Stastny, Jakub Ederer, Zuzana Nemeckova, Aleksandra Pogorzelska, Jakub Tolasz, Martin Kormunda, Petr Rysanek, Barbara Bazanow, Dominika Stygar, Karel Mazanec, Pavel Janos
Summary: Five different water-based precipitation methods were used to prepare nanoceria with varied redox properties and acid/base properties. The particle size, morphology, porosity, defect structure, and surface chemical composition of nanoceria played crucial roles in determining its reactivity in environmentally and biologically relevant reactions.
ENVIRONMENTAL SCIENCE-NANO
(2022)