Article
Materials Science, Multidisciplinary
Maria T. Colomer, Karent J. Duarte, Angel L. Ortiz, D. Fabio Mercado, Luz M. Ballesteros-Rueda
Summary: Doping of Pr3+ in TiO2 sols leads to reduced dispersion and increased viscosity, with lower doping proportions showing minimal crystal growth and minor transformation upon moderate calcination. Photocatalytic activity is highest in xerogels doped with 0.5 mol% Pr3+ and deteriorates with higher doping levels, while calcination at 500 degrees C decreases photocatalytic efficiency. These observations are attributed to changes in polymorph composition, crystal size, bandgap, and specific surface area with varying dopant content.
MATERIALS CHARACTERIZATION
(2021)
Review
Chemistry, Physical
Daniel Alves Barcelos, Maria Clara Goncalves
Summary: Visible-light-photoactive titania micro- or nanoparticles have shown great potential in various industrial applications, especially in environmental remediation. The sol-gel method, with its simplicity, versatility, and green chemistry approach, has been successfully employed for synthesizing crystalline and amorphous TiO2 micro- and nanoparticles. This short review aims to discuss the recent advancements in visible-light-photoactive titania-based nanoparticles for environmental remediation. Co-doping of titania, titania composite design, and the use of amorphous networks have been the most commonly used strategies to achieve this goal. Finally, predictions about the future developments in these fields are provided.
Article
Materials Science, Multidisciplinary
Beatriz Merillas, Judith Martin-de Leon, Fernando Villafane, Miguel A. Rodriguez-Perez
Summary: The concentration of catalyst has a significant impact on the synthesis and properties of polyisocyanurate-polyurethane aerogels, leading to the production of low-density materials with high porosities. By reducing the catalyst amount, the size of scattering centers, particles, and pores decreases, resulting in the creation of the first transparent aerogels in this system. These transparent aerogels have potential applications in solar collectors, glazing systems, and sensors.
ACS APPLIED POLYMER MATERIALS
(2021)
Article
Biochemistry & Molecular Biology
Danyal Naseer, Jang-Hoon Ha, Jongman Lee, Chanhyuk Park, In-Hyuck Song
Summary: In this study, a high-performance mesoporous alpha-alumina membrane was successfully fabricated using the sol-gel method. The surface properties of the membrane were improved and the membrane achieved the smallest reported pore size for pure alpha-alumina membranes.
Article
Materials Science, Ceramics
Narges Nasehi Gogajeh, Jafar Javadpour, Bijan Eftekhari Yekta
Summary: Bioactive glass microspheres (BGMs) were successfully produced using the sol-microemulsion-gel method, resulting in uniform and well-rounded microspheres under optimized conditions. Varying the reaction chamber size and stirring rate affected the diameter distribution of the microspheres, with increased stirring rate leading to the generation of smaller microspheres.
CERAMICS INTERNATIONAL
(2021)
Review
Chemistry, Physical
Julien G. Mahy, Louise Lejeune, Tommy Haynes, Stephanie D. Lambert, Raphael Henrique Marques Marcilli, Charles-Andre Fustin, Sophie Hermans
Summary: The work reviews an eco-friendly process for producing TiO2 via colloidal aqueous sol-gel synthesis, resulting in crystalline materials without a calcination step. The process is based on the hydrolysis of a Ti precursor in excess of water, followed by the peptization of precipitated TiO2, producing crystalline TiO2 nanoparticles without thermal treatment. The TiO2 photocatalysts have shown equivalent efficiency to those post-treated with thermal methods, presenting high surface area and crystalline phases, with potential applications in various fields like fuel cells and drug delivery systems.
Article
Materials Science, Ceramics
Ruohong Sui, John H. Jacobs, Nancy Chou, Connor E. Deering, Christopher B. Lavery, Robert A. Marriott
Summary: Both affordability and stability are crucial for commercial-scale production and industrial applications of TiO2. This study investigated a facile sol-gel process using titanyl sulfate as a feedstock, which resulted in the stable formation of anatase phase with bimodal mesopores and macropores. These unique nanostructures make it suitable for catalysis and filtration applications.
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
(2023)
Article
Polymer Science
Arpaporn Teamsinsungvon, Chaiwat Ruksakulpiwat, Penphitcha Amonpattaratkit, Yupaporn Ruksakulpiwat
Summary: In this study, titania-silica oxides were prepared using the sol-gel technique, and the effects of pH and Ti/Si atomic ratio on the structural characteristics of these oxides were investigated. The results showed that altering the Ti/Si ratio under alkaline conditions resulted in more uniform and minimized agglomeration of the nanoparticles.
Article
Chemistry, Multidisciplinary
Sanya Khursheed, Rida Tehreem, Muhammad Awais, Dilshad Hussain, Muhammad Imran Malik, Young Sun Mok, Ghayas Uddin Siddiqui
Summary: The purpose of this study was to investigate the effect of photocatalytic degradation using nitrogen and tungsten co-doped titania (TiO2) nanoparticles, which are cost-effective and environmentally friendly. The synthesized nanoparticles were analyzed using various techniques, including spectroscopy, microscopy, and spectrometry. The co-doping of metal and non-metal enhanced the photocatalytic properties of the TiO2 nanoparticles, particularly in the visible region. This resulted in improved absorption of visible light and reduced recombination of electron-hole pairs, leading to accelerated photodegradation. The bandgap of the titania nanoparticles was reduced after efficient doping, enabling the photodegradation of malachite green under visible light illumination. The results of photocatalytic degradation were confirmed using spectroscopy and high-performance liquid chromatography coupled with mass spectrometry.
Article
Materials Science, Paper & Wood
Andrey Zdravkov, Maria Listratenko, Stanislav Gorbachev, Iraida Osovskaya, Andrey Kanaev, Nikolai Khimich
Summary: Cellulose is used as a template agent to structure anatase TiO2 particles, forming MCC-TiO2 composite photocatalyst with organic-inorganic structures preserved. Materials prepared in caproic acid solvent showed higher photocatalytic activity, explained by the complementary nature of organic and inorganic components.
Article
Materials Science, Ceramics
Yu-Xuan Li, Ping Li, Yu-Zhe Wu, Zhen-Liang Xu, Ming-Ling Huang
Summary: A novel TiO2 thin film was prepared on ceramic hollow fibers using sol-gel method with PVP and PVA as additives. The effects of different PVP and PVA contents on the properties of TiO2 sol and the performance of ultrafiltration membranes were thoroughly investigated. The membrane with 1.0 wt% PVP and 0.8 wt% PVA showed superior separation performance and antifouling properties.
CERAMICS INTERNATIONAL
(2021)
Article
Optics
Manmohan Lal, Praveen Sharma, Chhotu Ram
Summary: The study found that the calcination temperature has a significant impact on the crystalline properties, band gap, and morphology of TiO2 nanoparticles. Temperatures above 700 degrees Celsius shift the TiO2 spectra to the visible region, while at 400 degrees Celsius the crystalline size of TiO2 nanoparticles is 7.68 nanometers.
Article
Materials Science, Ceramics
Nan Li, Di An, Zhongzhou Yi, Nuoting Yu, Zhipeng Xie
Summary: A novel sol-gel-flux method was used to synthesise 1Y6Ce-ZrO2 nanoparticles, with the NaCl + KCl system showing lower preparation temperature and improved dispersion and sintering performance compared to the NaCl system.
CERAMICS INTERNATIONAL
(2022)
Article
Materials Science, Ceramics
E. K. Papynov, O. O. Shichalin, V. I. Apanasevich, N. G. Plekhova, I. Yu Buravlev, S. V. Zinoviev, V. Yu Mayorov, A. N. Fedorets, E. B. Merkulov, D. Kh Shlyk, V. A. Nepomnyushchaya, Z. E. Kornakova, I. S. Afonin, I. O. Evdokimov, O. V. Korshunova
Summary: This article describes an original sol-gel method for synthesizing dispersed nanostructured wollastonite and its composite with hydroxyapatite, as well as functionalized form with gold nanoparticles. Various analytical methods were used to study the structure and morphology of the samples, as well as the functional activity of immune cells in contact with the materials. This study provides valuable insights into the biocompatibility and quality evaluation of biomaterials used in bone grafting.
CERAMICS INTERNATIONAL
(2021)
Article
Materials Science, Ceramics
Shakoor Ahmad, Muhammad Aadil, Syeda Rabia Ejaz, Muhammad Usman Akhtar, Hadia Noor, Sajjad Haider, Ibrahim A. Alsafari, Ghazala Yasmin
Summary: Industrial pollution has caused water contamination by toxic dyes and pathogenic microbes leading to a need for effective photocatalysis techniques. Researchers have developed a ZnO/SrZnO2 composite as a highly efficient photocatalyst capable of mineralizing dyes and exhibiting antibacterial properties, showing significant potential for water treatment.
CERAMICS INTERNATIONAL
(2022)
Article
Engineering, Environmental
Umer Khalil, Zhendong Liu, Ce Peng, Naomichi Hikichi, Toru Wakihara, Javier Garcia-Martinez, Tatsuya Okubo, Sankar Bhattacharya
Summary: Introducing intracrystalline mesoporosity to zeolites through surfactant-templating can be achieved quickly and effectively, enhancing their catalytic performance.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Chemistry, Physical
Sayyed Mahdi Hossein, Mehran A. Ghiaci, Sergei A. Kulinich, Wilfried S. Wunderlich, Hassan S. Ghaziaskar, Amin Javaheri Koupaei
Summary: This study fabricated a novel nanocomposite Co/N-CFF@TiO2-SiO2 catalyst, which improved the mechanical, chemical and thermal stabilities of carbon fiber felt. The catalyst demonstrated good catalytic activity and excellent long-term stability in the oxidation of ethyl benzene.
APPLIED CATALYSIS A-GENERAL
(2022)
Article
Chemistry, Applied
Peidong Hu, Kenta Iyoki, Haruko Fujinuma, Jingyun Yu, Sijing Yu, Chokkalingam Anand, Yutaka Yanaba, Tatsuya Okubo, Toru Wakihara
Summary: This study successfully achieved fast synthesis of SSZ-39 zeolites directly from colloidal silica and sodium aluminate, with critical impacts of reactant alkalinity and NaOH content on phase selectivity discovered. Partial replacement of Na+ with K+ can eliminate impurity formation, and the fast and direct synthesis route shows potential for high-quality SSZ-39 zeolite production.
MICROPOROUS AND MESOPOROUS MATERIALS
(2022)
Article
Chemistry, Physical
Zhendong Liu, Anand Chokkalingam, Shoko Miyagi, Masato Yoshioka, Tomoya Ishikawa, Hiroki Yamada, Koji Ohara, Nao Tsunoji, Yusuke Naraki, Tsuneji Sano, Tatsuya Okubo, Toru Wakihara
Summary: Interzeolite conversion provides a new way to study zeolite synthesis, with experiments revealing conversion patterns from FAU to AEI and confirming the importance of altering the initial FAU structure in determining synthesis outcomes. Dealumination proves effective in modifying the FAU structure, facilitating successful conversion to the target AEI zeolite. Insights obtained from interzeolite conversion can also aid in the successful synthesis of zeolites from dealuminated amorphous aluminosilicate precursors.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Raquel Simancas, Masamori Takemura, Yasuo Yonezawa, Sohei Sukenaga, Mariko Ando, Hiroyuki Shibata, Anand Chokkalingam, Kenta Iyoki, Tatsuya Okubo, Toru Wakihara
Summary: This study investigates the effect of external hydrostatic pressure on the hydrothermal synthesis of microporous silicoaluminophosphate SAPO-18. The results demonstrate that under high pressure conditions, the formation of SAPO-18 phase is inhibited when using relatively diluted synthesis mixtures, while concentrated synthesis mixtures allow for the formation of SAPO-18.
Article
Chemistry, Physical
Sheyda Nilforoushan, Mehran Ghiaci, Sayyed Mahdi Hosseini, Sergei A. Kulinich, Wilfried Wunderlich, Hossein Farrokhpour
Summary: In this study, a simple method was reported to create gold nanoparticles coated-double silica shells with narrow size distribution. The nanoparticles showed high catalytic activity and selectivity in the aerobic oxidation of cyclohexane under mild conditions.
APPLIED SURFACE SCIENCE
(2022)
Article
Engineering, Chemical
Ayano Minami, Masanori Takemoto, Yasuo Yonezawa, Zhendong Liu, Yutaka Yanaba, Anand Chokkalingam, Kenta Iyoki, Tsuneji Sano, Tatsuya Okubo, Toru Wakihara
Summary: In this study, ultrafast dealumination of zeolites was achieved using a continuous-flow system, resulting in enhanced catalytic activity and thermal/hydrothermal stabilities while maintaining the original crystalline structure and particle morphology. The dealumination process completed within 1 minute at 200 degrees C significantly improved the hydrothermal stability of the zeolite.
ADVANCED POWDER TECHNOLOGY
(2022)
Article
Multidisciplinary Sciences
Tatsushi Yoshioka, Kenta Iyoki, Yuusuke Hotta, Yoshihiro Kamimura, Hiroki Yamada, Qiao Han, Takeharu Kato, Craig A. J. Fisher, Zhendong Liu, Ryohji Ohnishi, Yutaka Yanaba, Koji Ohara, Yukichi Sasaki, Akira Endo, Takahiko Takewaki, Tsuneji Sano, Tatsuya Okubo, Toru Wakihara
Summary: This study demonstrates a postsynthetic approach named POMP to tune the composition of small-pore zeolites by removing aluminum species and improving hydrothermal stability through defect healing. These findings could facilitate industrial applications of small-pore zeolites.
Article
Engineering, Chemical
Junki Tomita, Shanmugam P. Elangovan, Keiji Itabashi, Anand Chokkalingam, Haruko Fujinuma, Zhigang Hao, Akihiro Kanno, Katsuhiko Hayashi, Kenta Iyoki, Toru Wakihara, Tatsuya Okubo
Summary: The synthesis of zeolite beta without organic structure directing agents (OSDAs) is achieved through the addition of seed crystals. However, using OSDA-free synthesized zeolite beta as seed crystals is challenging and leads to the formation of mordenite zeolite as a contaminant. In this study, a successful post-synthetic powder technology is demonstrated for retrieving pure zeolite beta seed particles that were originally mixed with mordenite impurity. The technique involves centrifugation and allows for the segregation of pure beta microparticles for use as OSDA-free beta seeds. The recycling of this technique is successful for up to three generations. It was also found that controlling the silicon to aluminum ratio and using acid and alkali treatments aid in the formation of pure phase zeolite beta.
ADVANCED POWDER TECHNOLOGY
(2022)
Article
Materials Science, Multidisciplinary
Samaneh Farjadfar, Mehran Ghiaci, Sergei A. Kulinch, Wilfried Wunderlich
Summary: This study reports on a low-cost synthesis of nanocomposites consisting of carbon dots trapped in a matrix of titanium dioxide. The prepared photocatalysts showed excellent performance in degrading organic contaminants under visible light irradiation. The materials also exhibited good thermal and chemical stability. The study provides an important step towards the rational design of highly active photocatalysts.
MATERIALS RESEARCH BULLETIN
(2022)
Article
Chemistry, Applied
Yuki Sada, Shoko Miyagi, Kenta Iyoki, Masato Yoshioka, Tomoya Ishikawa, Yusuke Naraki, Tsuneji Sano, Tatsuya Okubo, Toru Wakihara
Summary: The flexible control of composition and atomic arrangement is the ultimate goal in materials science. The study successfully synthesized a high-silica zeolite with biased Al distribution.
MICROPOROUS AND MESOPOROUS MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Ayano Minami, Peidong Hu, Yuki Sada, Hiroki Yamada, Koji Ohara, Yasuo Yonezawa, Yukichi Sasaki, Yutaka Yanaba, Masanori Takemoto, Yuki Yoshida, Tatsuya Okubo, Toru Wakihara
Summary: This study investigates the amorphous-to-crystalline transformation of SSZ-13 zeolite during hydrothermal synthesis using in situ high-energy X-ray total scattering measurement. The results show that ordered four-membered rings dominate the induction period, while six- and eight-membered rings increase significantly during the crystal growth stage. These preformed ordered rings contribute to the formation of composite building units containing six- and eight-membered rings, facilitating the construction and growth of zeolite crystals.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Materials Science, Multidisciplinary
Masanori Takemoto, Kenta Iyoki, Yuki Otsuka, Hiroaki Onozuka, Anand Chokkalingam, Toshiyuki Yokoi, Susumu Tsutsuminai, Takahiko Takewaki, Toru Wakahira, Tatsuya Okubo
Summary: This study demonstrates the remarkably prolonged lifetime of a CON-type zeolite in methanol-to-olefins reaction via a multistep strategy including post-milling recrystallisation and liquid-mediated healing of residual defects. The defect-healed zeolite nanoparticles showed a lifetime more than twice that of the parent zeolite owing to the increased external surface area and the reduced subnano-scale defects. This protocol could play a significant role in designing robust catalysts with controlled particle sizes and reduced subnano-scale defects.
MATERIALS ADVANCES
(2022)
Article
Materials Science, Ceramics
Kenta Iyoki, Takako Onishi, Mariko Ando, Sohei Sukenaga, Hiroyuki Shibata, Tatsuya Okubo, Toru Wakihara
Summary: When zeolites are synthesized in fluoride-containing media, large crystals tend to be obtained. In this research, a multi-stage synthesis strategy for size reduction of silicalite-1 in fluoride-containing media is presented. Increasing the number of effective nuclei is crucial for size reduction.
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN
(2022)
Proceedings Paper
Computer Science, Theory & Methods
Wilfried Wunderlich
Summary: This paper discusses the importance of communication in the success of AI-based social systems. It introduces the concept of chatbots for responding to incoming messages and the evaluation of their effectiveness in a chatroom connected to live web cameras. The results highlight the need to differentiate responses based on ethics and social dilemmas for future applications.
INTERNATIONAL CONFERENCE ON ELECTRICAL, COMPUTER AND ENERGY TECHNOLOGIES (ICECET 2021)
(2021)
