Article
Materials Science, Multidisciplinary
Kumud Dubey, Shubha Dubey, Anchit Modi, R. K. Sharma, Sujay Chakravarty, C. Parvathiraja, N. K. Gaur
Summary: Complex BiMn2O5 nanoparticles were successfully synthesized through a novel ultrasonication assisted sol-gel synthesis route. The nanoparticles exhibited desirable properties for applications in photocatalysts and magnetic materials.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2023)
Article
Materials Science, Ceramics
Swapnil A. Jadhav, Mangesh Khedkar, Deepali D. Andhare, S. B. Gopale, K. M. Jadhav
Summary: Ni-Zn ferrite nanoparticles were prepared using sol-gel auto combustion technique and applied for the removal of Rhodamine B from industrial waste-water. The nanoparticles were characterized for structure, crystalline size, and optical properties, showing good photocatalytic degradation performance under sunlight.
CERAMICS INTERNATIONAL
(2021)
Article
Engineering, Chemical
M. Faisal, Mohammed Jalalah, Farid A. Harraz, Ahmed Mohamed El-Toni, Joselito P. Labis, M. S. Al-Assiri
Summary: The study successfully synthesized Ag and PANI doped ZnTiO3 ternary photocatalyst, demonstrating its high efficiency in environmental remediation. The formation of the novel ternary photocatalyst altered the bandgap energy of ZnTiO3 and exhibited excellent degradation performance under visible light illumination.
SEPARATION AND PURIFICATION TECHNOLOGY
(2021)
Article
Engineering, Chemical
M. Faisal, Md A. Rashed, Jahir Ahmed, M. A. M. Alhmami, M. K. Asif Khan, Mohammed Jalalah, S. A. Alsareii, Farid A. Harraz
Summary: The study designed a highly efficient visible light ternary photocatalyst by combining ZnTiO3 nanostructures, chitosan, and platinum nanoparticles, which successfully degraded 94.48% of the target insecticide within 25 minutes, exhibiting ultrafast performance.
JOURNAL OF THE TAIWAN INSTITUTE OF CHEMICAL ENGINEERS
(2022)
Article
Chemistry, Physical
N. H. Erdogan, T. Kutlu, N. Sedefoglu, H. Kavak
Summary: Undoped ZnO films and Na-doped ZnO films with different Na/Zn molar ratios were deposited on glass substrates by the sol-gel spin coating method. Sodium doping significantly influenced the structure and properties of the films, resulting in different electrical conductivity and optical characteristics.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Engineering, Electrical & Electronic
M. Faisal, Jahir Ahmed, Jari S. Algethami, Ahmed Mohamed El-Toni, Joselito P. Labis, Aslam Khan, Farid A. Harraz
Summary: A novel visible light ternary photocatalytic structure based on mesoporous ZnO combined with chitosan (CSN) and gold nanoparticles (AuNPs) was synthesized and proven to be highly efficient in removing insecticide and dye under visible light illumination. The as-fabricated Au@CSN/ZnO nanocomposite showed 211% higher efficiency than bare mesoporous ZnO in removing insecticide and rapid destruction of dye. In addition, the photocatalyst exhibited good stability and recyclability, making it suitable for practical application in environmental remediation.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2023)
Article
Environmental Sciences
Mehala Kunnamareddy, Sivarasan Ganesan, Ashraf Atef Hatamleh, Bassam Khalid Alnafisi, Ranjith Rajendran, Ragavendran Chinnasamy, Priyadharsan Arumugam, Barathi Diravidamani, Huang-Mu Lo
Summary: In this study, Cobalt Sulfur codoped Titanium Dioxide (Co-S codoped TiO2) photocatalysts were synthesized using the sol-gel technique. The characterization results showed that the synthesized nanoparticles had excellent crystallinity, high purity, and superior optical characteristics. The Co-S codoped TiO2 nanoparticles exhibited improved catalytic activity, degrading 93% of the methylene blue (MB) in 120 minutes. They also demonstrated strong antibacterial activity against both Gram negative and Gram positive bacteria.
ENVIRONMENTAL RESEARCH
(2023)
Article
Engineering, Electrical & Electronic
Pornnipa Nunocha, Malinee Kaewpanha, Theerachai Bongkarn, Anukorn Phuruangrat, Tawat Suriwong
Summary: In this study, Sr1-xLaxTiO3 (SLTO) nanopowders with varied La contents were synthesized using a sol-gel auto combustion technique. The La doping affected the crystal structure, particle size, specific surface area, optical properties, and photocatalytic activity of SLTO.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2021)
Article
Environmental Sciences
Ashwini S. Varpe, Mrinalini D. Deshpande, Dipak R. Tope, Ashok V. Borhade
Summary: CdFe2O4/Al2O3 magnetic nanocomposite photocatalyst is synthesized by sol-gel auto-combustion method, and its role as a photocatalyst is studied. The influence of Al2O3 concentration on the photocatalytic property is investigated. The 10% composite sample shows superior properties compared to other concentrations and bare CdFe2O4 nanoparticles. The degradation rate of xylenol orange dye reaches 92.29% after 30 minutes of photocatalytic reaction.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Materials Science, Ceramics
I. A. Mkhalid
Summary: In this study, a sol-gel-based process was used to prepare Ag2O/SrAl2O4/CNT ternary nanocomposites, which exhibited visible-light response and enhanced photocharge mobility. The 3.0 wt% Ag2O/SrAl2O4/4.0% CNT photocatapyst showed improved performance in hydrogen evolution, attributed to the precise amounts of Ag2O and CNTs added.
CERAMICS INTERNATIONAL
(2022)
Article
Chemistry, Physical
M. Faisal, Jahir Ahmed, Jari S. Algethami, Ali S. Alkorbi, Saeed A. Alsareii, Farid A. Harraz
Summary: Surface modification and bandgap engineering of ZnTiO3 is important for improving its photocatalytic performance. In this study, a ternary photocatalyst composed of ZnTiO3 nanostructures, polypyr-role doped carbon back (PPy-C), and gold nanoparticles (Au NPs) was developed. The synthesized Au@PPy-C/ZnTiO3 photocatalyst showed enhanced degradation efficiency under visible light illumination compared to bare ZnTiO3, attributed to its well-ordered mesoporous structure, high surface area, and effective decline in recombination rate of charge carriers.
JOURNAL OF MOLECULAR LIQUIDS
(2023)
Article
Engineering, Chemical
M. Faisal, Mabkhoot Alsaiari, Md. A. Rashed, Farid A. Harraz
Summary: The study aimed to create novel and highly influential photocatalyst frameworks utilizing ZnO/SnO2 nanocomposites and active carbon (AC) to address environmental concerns. The fabricated 10% AC@ZnO/SnO2 nanocomposites showed remarkable removal of target antibiotics and destruction of insecticides and MB complex structures under visible light conditions.
JOURNAL OF THE TAIWAN INSTITUTE OF CHEMICAL ENGINEERS
(2021)
Article
Optics
Vijay Singh, Sumandeep Kaur, A. S. Rao
Summary: A series of CaY2Al4SiO12 garnet phosphors doped with different concentrations of Sm3+ were prepared using the sol-gel method. Structural investigations, optical band gap determination, and luminescence behavior studies were conducted. The results showed the potential utility of the prepared garnet phosphor in display and lighting devices.
Article
Materials Science, Ceramics
M. Sertkol
Summary: In this study, Mn0.5Zn0.5CdxFe2-xO4 (0.0 <= x <= 0.5) nanoparticles were successfully synthesized by sol-gel combustion approach, and the effects of cadmium on their structural, morphological, and magnetic properties were investigated. It was found that the magnetization value of the nanoparticles increased with lower Cd2+ doping content and then decreased gradually.
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
(2022)
Article
Chemistry, Multidisciplinary
Mina Dara, Mohammad Hassanpour, Omid Amiri, Mahin Baladi, Masoud Salavati-Niasari
Summary: The importance of water leads to the continuous development of new methods and materials to improve freshwater quality. This study synthesized novel Tb2CoMnO6 nanoparticles and investigated their unique properties in the photocatalytic process, with particles synthesized in the presence of maltose in an equal ratio to the precursor showing the best performance.
ARABIAN JOURNAL OF CHEMISTRY
(2021)
Article
Engineering, Environmental
Srinu Akula, Marek Mooste, Jekaterina Kozlova, Maike Kaarik, Alexey Treshchalov, Arvo Kikas, Vambola Kisand, Jaan Aruvali, Paarn Paiste, Aile Tamm, Jaan Leis, Kaido Tammeveski
Summary: Delving into highly active and cost-efficient electrocatalysts for oxygen reduction reaction (ORR) is crucial for large-scale application of polymer electrolyte fuel cells. Anion exchange membrane fuel cells (AEMFCs) are promising clean energy devices with mild reaction conditions and the possibility of employing Pt-free catalysts for ORR. This study focuses on the development of non-Pt catalysts for AEMFC by preparing metal-nitrogen-carbon (M-N-C) electrocatalysts through a robust synthesis method using transition metal impregnated melamine-phloroglucinol-formaldehyde (MPF) polymeric networks. The catalysts with optimized metal content and pyrolysis temperature showed enhanced ORR performance due to their prominent textural properties and efficient active centers. Iron-doped (MPF/Fe) and cobalt-doped (MPF/Co) catalysts performed the best with half-wave potential (E1/2) values of 0.81 and 0.80 V vs RHE, attributed to the highly active M-Nx sites and hierarchical porous structure. The outstanding electrochemical stability and high-power density in AEMFC (up to 347 mW cm-2) demonstrate the potential of these M-N-C catalysts for fuel cell applications.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Electrochemistry
Jaana Lilloja, Marek Mooste, Elo Kibena-Poldsepp, Ave Sarapuu, Arvo Kikas, Vambola Kisand, Maike Kaarik, Jekaterina Kozlova, Alexey Treshchalov, Paarn Paiste, Jaan Aruvali, Jaan Leis, Aile Tamm, Steven Holdcroft, Kaido Tammeveski
Summary: Cobalt-, iron- and nitrogen-doped ordered mesoporous carbon (OMC)-based electrocatalysts are prepared and characterized as cathode catalysts for anion-exchange membrane fuel cell (AEMFC). The doped catalysts show high electrocatalytic activity and stability, with CoFe-N-OMC/CNT achieving the highest peak power density of 336 mW cm-2 in AEMFC testing.
ELECTROCHIMICA ACTA
(2023)
Article
Chemistry, Physical
Jonas Mart Linge, Heiki Erikson, Marek Mooste, Helle-Mai Piirsoo, Tiit Kaljuvee, Arvo Kikas, Jaan Aruvali, Vambola Kisand, Aile Tamm, Arunachala M. Kannan, Kaido Tammeveski
Summary: Two different wet chemical methods were used to deposit silver nanocatalyst (40 wt%) on commercial mesoporous carbon support material (Ag/C) to enhance the electrochemically active surface area. The catalyst materials were characterized using various analytical techniques and evaluated for oxygen reduction reaction (ORR) in alkaline media. The Ag/C catalyst exhibited higher mass activity for ORR compared to Vulcan carbon, showing potential for application in anion exchange membrane fuel cells.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Chemistry, Analytical
Gulnara Yusibova, Jurgen-Martin Assafrei, Kefeng Ping, Jaan Aruvali, Paam Paiste, Maike Kaarik, Jaan Leis, Helle-Mai Piirsoo, Aile Tamm, Arvo Kikas, Vambola Kisand, Pavel Starkov, Nadezda Kongi
Summary: This study presents a new ligand-enabled strategy for incorporating dual metals into metal-organic-framework-derived bifunctional oxygen electrocatalysts. The involvement of bimetallic systems reduces the need for critical raw materials and enhances the overall electroactivity of the catalyst. A mixed-metal manganese/cobalt metal-organic framework (TAL-42) is introduced as a versatile single precursor for the facile preparation of highly efficient bifunctional oxygen electrocatalysts. The TAL-42-900 material exhibits superior bifunctional oxygen reduction/evolution reaction performance compared to a commercial Pt/C + RuO2 catalyst.
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Artis Linarts, Peter C. Sherrell, Kaspars Malnieks, Amanda V. Ellis, Andris Sutka
Summary: A new paradigm of triboelectric polymers, the triboelectric laminate, is reported, which shows electromechanical response comparable to polyvinylidene difluoride. The response in the laminate arises from aligned dipoles generated by contact electrification. The loose interface between different polymer fibers ensures friction and triboelectric charging.
Article
Pharmacology & Pharmacy
Abhijit Biswas, Maria Maloverjan, Kart Padari, Aare Abroi, Margus Ratsep, Sebastian K. T. S. Warmlander, Juri Jarvet, Astrid Graslund, Vambola Kisand, Runno Lohmus, Margus Pooga
Summary: Cell-penetrating peptides (CPPs) are promising transfection agents for delivering compounds into living cells. The properties of the resulting CPP particles in an aqueous solution depend on the solvent used for dissolving the CPP. Using different methods, such as dynamic light scattering and microscopy, it was found that CPPs dissolved in organic solvents form uniform particles, while those dissolved in water tend to form aggregates and micelles.
Article
Chemistry, Physical
Madis Luesi, Heiki Erikson, Helle -Mai Piirsoo, Jaan Aruvali, Arvo Kikas, Vambola Kisand, Aile Tamm, Kaido Tammeveski
Summary: Galvanic exchange was used to prepare AgPd nanocatalysts. The particle sizes were determined to be 10-20 nm, and the AgPd particles obtained using MP-AES had a larger Ag/Pd ratio compared to those obtained using other ratios. The galvanic exchange process resulted in porous and halfmoon shaped particles. Increasing Pd content led to lower mass activities for oxygen reduction reaction (ORR) despite higher specific activity values on larger particles. A Tafel slope value of -60 mV was observed for all the AgPd catalysts.
APPLIED SURFACE SCIENCE
(2023)
Article
Chemistry, Physical
Kaur Muuli, Andri Sokka, Marek Mooste, Jaana Lilloja, Viktoria Gudkova, Maike Kaarik, Markus Otsus, Arvo Kikas, Vambola Kisand, Aile Tamm, Jaan Leis, Andres Krumme, Steven Holdcroft, Jose H. Zagal, Kaido Tammeveski
Summary: This study synthesized co-doped polyacrylonitrile-based electrospun carbon nanofibre catalysts and investigated the effects of carbonization temperature, acid leaching conditions, presence of ionic liquid, and metal phthalocyanine content. The catalyst with the highest oxygen reduction reaction (ORR) activity showed a half-wave potential of 857 mV and a maximum power density of 231 mW cm-2 when used as a cathode catalyst in an anion-exchange membrane fuel cell (AEMFC).
JOURNAL OF CATALYSIS
(2023)
Review
Electrochemistry
Janis Kleperis, Gunars Bajars, Liga Grinberga, Guntars Vaivars, Juris Purans, Girts Vitins, Gints Kucinskis
Summary: Solid state ionics is a key research topic at the Institute of Solid State Physics, University of Latvia. Their research spans from electrochromic phenomena to materials for rechargeable batteries and hydrogen energy. The institute is recognized as one of the leading centers in the USSR and Eastern Europe and continues to excel in the field of solid state ionics. Their extensive historical review highlights the development and achievements of solid state ionics from the institute's establishment to the present day. Currently, they collaborate with partners across Europe and beyond, further establishing themselves as a center of research excellence in solid state ionics.
JOURNAL OF SOLID STATE ELECTROCHEMISTRY
(2023)
Article
Chemistry, Physical
Jaana Lilloja, Elo Kibena-Poldsepp, Ave Sarapuu, Anastasiia Konovalova, Maike Kaarik, Jekaterina Kozlova, Paarn Paiste, Arvo Kikas, Alexey Treshchalov, Jaan Aruvali, Andrea Zitolo, Jaan Leis, Aile Tamm, Vambola Kisand, Steven Holdcroft, Kaido Tammeveski
Summary: Transition-metal and nitrogen-doped graphene-like material and carbon nanotube composites are synthesized and utilized as cathode catalysts in anion exchange membrane fuel cells. The materials exhibit similar physicochemical properties and electrocatalytic performances with different yields of HO2- formation. The M-N-Gra/CNT catalysts, especially CoFe-N-Gra/CNT, combined with Aemion+ reinforced anion-exchange membrane, show excellent AEMFC performance comparable to that of Pt/C with a peak power density of 638 mW cm(-2), attributed to the presence of M-Nx sites, carbon-encapsulated transition-metal nanoparticles, and nitrogen-containing moieties.
ACS APPLIED ENERGY MATERIALS
(2023)
Article
Electrochemistry
Jaanus Kruusma, Tanel Kaambre, Arvo Tonisoo, Vambola Kisand, Karmen Lust, Enn Lust
Summary: The electrochemical behaviour of Al as a current collector in different electrochemical power sources was investigated using the in situ soft X-ray photoelectron spectroscopy (XPS) method. Physical and electrochemical information about the Al-current-collector RTIL interface soaked in N4111(TFSI) ionic liquid was obtained through cyclic voltammetry, electrochemical impedance spectroscopy, and synchrotron in situ soft XPS methods. The obtained data showed the start of intensive oxidation processes and the electro-oxidation of TFSI- anions.
Article
Chemistry, Physical
Ivar Kuusik, Mati Kook, Rainer Parna, Vambola Kisand
Summary: Ultraviolet photoelectron spectroscopy (UPS) measurements were used to study the electronic binding energies of EMIM-DCA vapor. Density functional theory (DFT), Moller-Plesset perturbation theory (MP2), and many-body perturbation theory calculations (GW) were used to interpret the measured spectra. The results showed that the hybrid DFT functionals, which worked well for other ionic liquid vapors, had shortcomings in the case of EMIM-DCA. MP2 calculation and the quasiparticle GW approach provided a better description of the experimental UPS spectra. Charge distribution analysis revealed a favorable charge transfer from the cation to the anion upon ionization.
Article
Energy & Fuels
Ansis Mezulis, Christiaan Richter, Peteris Lesnicenoks, Ainars Knoks, Sarunas Varnagiris, Marius Urbonavicius, Darius Milcius, Janis Kleperis
Summary: This study aims to explain the kinetics of aluminum hydrolysis reaction by using a suitable theoretical model and machined aluminum waste chips with alkali solutions. The purpose is to evaluate the optimal concentration of alkali for small- and medium-scale green hydrogen production. By analyzing surface chemical reactions and mass transfer rate steps, the researchers obtained important parameters and achieved a high yield of H-2 gas. The estimation of profit takes into account the price and consumption of alkali, and reveals positive profit even with the use of chemical-grade alkali.
Article
Materials Science, Multidisciplinary
Liva Germane, Linards Lapcinskis, Mairis Iesalnieks, Andris Sutka
Summary: We have demonstrated a method to significantly enhance the triboelectric charge in the contact-separation of identical PDMS contact layers by three orders of magnitude. This improvement is achieved by functionalizing the PDMS with self-assembled monolayers (SAMs) and combining rough and smooth surfaces. The SAM-modified PDMS exhibits a more stable surface charge compared to pristine PDMS.
MATERIALS ADVANCES
(2023)
Article
Nanoscience & Nanotechnology
Kristjan Kalam, Peeter Ritslaid, Tanel Kaeaembre, Aile Tamm, Kaupo Kukli
Summary: Polycrystalline SnO2 thin films were successfully grown on SiO2/Si(100) substrates using atomic layer deposition. The relationship between growth per cycle and substrate temperature was determined, and crystal growth was observed in the temperature range of 225-600 degrees C. Spectroscopic analyses revealed low residual iodine content and the formation of single-phase oxide in films grown at temperatures above 300 degrees C. The suitability of the precursor system for preparing SnO2 films was confirmed.
BEILSTEIN JOURNAL OF NANOTECHNOLOGY
(2023)
