Article
Chemistry, Physical
Mohini Panday, Gaurav K. Upadhyay, L. P. Purohit
Summary: Antimony-doped SnO2 thin films were prepared and tested as gas and humidity sensors. The results showed that the doping of antimony can significantly affect the optical and electrical properties of the films, leading to excellent sensing response at different temperatures and humidities.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Nanoscience & Nanotechnology
Maximiliano Jesus Jara Fornerod, Alberto Alvarez-Fernandez, Eric R. Williams, Maximilian W. A. Skoda, Beatriz Prieto-Simon, Nicolas H. Voelcker, Morgan Stefik, Marc-Olivier Coppens, Stefan Guldin
Summary: Mesoporous thin films are widely used for their high surface area and efficient mass and charge transport properties. A two-step calcination process can reduce film contraction and enhance structural control, resulting in mesoporous films with higher porosity and larger pores. These films exhibit favorable characteristics for mass transport of large molecules.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Inorganic & Nuclear
Habib Chenaina, Charfeddine Messaadi, Jalila Jalali, Hatem Ezzaouia
Summary: This study focuses on sol-gel derived SnO2-TiO2 thin films deposited on silicon wafer type Si (100) substrate using spin coating technique, followed by heat treatments at four different temperatures. XRD characterization reveals the formation of nano-crystalline phase at 400 degrees C and further crystallization with increasing annealing temperature. Optical and dielectric properties analysis demonstrates universal many body response over a broad frequency range, presenting variations in structure and performance of the films.
INORGANIC CHEMISTRY COMMUNICATIONS
(2021)
Article
Materials Science, Ceramics
Leodoro P. dos Santos Filho, de F. P. Maria P. Nascimento, Liziane Marcal, Katia J. Ciuffi, Marcio L. A. e Silva, Eduardo J. Nassar, Lucas A. Rocha
Summary: The sol-gel process is an interesting strategy to obtain hybrid materials, with mesoporous silica showing large specific area and pore volume, and demonstrating efficient antimicrobial properties. Mesoporous silica matrixes prepared via the sol-gel process using surfactants and copolymers as structure-driving agents showed the most significant effects in the study.
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
(2021)
Article
Materials Science, Ceramics
Gizem Aydin Sobaci, Osman Burak Okan, Kursat Kazmanli, Refika Budakoglu
Summary: This study investigates the potential of using dual alkoxysilane precursor chemistry for depositing antireflection thin films on glass. The results show that the dual precursor chemistry can produce coatings with high mechanical and chemical resistance, while maintaining their antireflective properties during industrial tempering processes. The study also demonstrates that the laboratory dip coating process can be scaled up to a roller coating process for commercial solar modules and patterned glasses.
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
(2022)
Article
Chemistry, Physical
Genis Vanheusden, Harold Philipsen, Sebastiaan J. F. Herregods, Philippe M. Vereecken
Summary: This study demonstrates the importance of diffusion layer control using a rotating disk electrode to produce aggregate-free films in a wide thickness range (11-2500 nm). Factors such as electrode rotation rate, deposition time/charge, current, and temperature were found to affect the deposition rate.
CHEMISTRY OF MATERIALS
(2021)
Article
Optics
R. Dridi, D. Dridi, S. Hammami, W. Dimassi, R. Chtourou, M. Amlouk
Summary: In this study, NiWO4 thin films of 200 nm thickness were successfully deposited on FTO substrates using a sol-gel method via spin coating for gas sensor applications. The films were investigated for their structural, morphological, and optical properties. XRD analysis confirmed a polycrystalline nature with a crystallite size of 80 nm. Raman spectroscopy confirmed the presence of NiWO4. The films displayed uniform surfaces with particles of approximately 50 nm. The NiWO4 exhibited a direct band gap of 2.77 eV. Charge transfer processes at the NiWO4/electrolyte interface were characterized by electrochemical impedance spectroscopy. The NO2 sensing performance of the films was evaluated at low temperatures ranging from 170°C to 260°C.
Article
Materials Science, Multidisciplinary
Adil Alshoaibi, Shumaila Islam
Summary: The opto-chemical sensing matrices, D-SNIPs, D-TNIPs, and D-STNPs, exhibit thermally stable, large surface area, and different refractive indices. The prepared sensors show a linear response, non-leachability, stability towards high pH 12, and fast time response, making them suitable for practical pH sensing applications.
MATERIALS RESEARCH BULLETIN
(2021)
Article
Materials Science, Multidisciplinary
Zhou Li, David W. W. Gardner, Yong Xia, Sikai Zhao, Aifei Pan, Nishit Goel, Stephen Bart, Chen Liu, Jianxin Yi, Carlo Carraro, Roya Maboudian
Summary: Ordered porous thin films of reduced graphene oxide and tin oxide (rGO/SnO2) were synthesized and their gas-sensing properties were studied. The incorporation of rGO significantly improved the humidity sensitivity and electrical conductivity of the sensor. The rGO/SnO2 composite film also demonstrated fast response time and excellent selectivity towards humidity, and showed long-term stability compared to a commercial humidity sensor.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
Article
Multidisciplinary Sciences
Amany M. El Nahrawy, Ali B. Abou Hammad, A. M. Mansour
Summary: Mesoporous P2O5 doped magnesium silicate (MS-P) thin films were prepared using the activated sol-gel method and calcinated at different temperatures. The study examined the effects of P2O5 content and calcinating temperature on the structure and optical properties of thin films, showing significant impacts on crystallization and optical band gap. The films demonstrated high transmittance in the visible range, with a blue shift in the optical band gap as P2O5 content and calcinating temperature increased. Refractive index remained constant in the visible zone.
ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING
(2021)
Article
Electrochemistry
Pei-Te Lin, Chih-Ying Yu, Sin-Huei Ho, Shiuan-Wei Pan, Jyun-Siang Jhang, Yi-Xun Zhang, Yo-Lun Zhang, Tian-Tsz Hsieh, Hao-Chien Wang, Wen-Jeng Hsueh, Chun-Ying Huang
Summary: The photochemical activation process is a promising way to operate metal oxide gas sensors at room temperature, but currently limited to n-type semiconductors. In this study, a highly stable p-type copper gallium oxide (CuGaO2) gas sensor was fabricated through the facile sol-gel process. It can detect O-3 gas at room temperature and its gas response can be further enhanced by UV activation, achieving a highest gas response of 7.12 to 5 ppm O-3 gas at a UV intensity of 10 mW cm(-2). Additionally, the CuGaO2 sensor exhibits excellent long-term stability with only approximately 3% degradation over 90 days.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
J. J. Mikolei, D. Richter, R. Pardehkhorram, C. Helbrecht, S. Schabel, T. Meckel, M. Biesalski, M. Ceolin, A. Andrieu-Brunsen
Summary: Introduces the importance of mesopores in paper, which not only increase the specific surface area, but also have specific properties such as capillary fluid transport and ion specific pore accessibility. Investigates mesopore formation in paper using sol-gel chemistry and evaporation induced self-assembly, and discusses the influence of solvent evaporation rate and capillary fluid velocity on mesopore formation.
Article
Chemistry, Analytical
Pei-Shan Huang, Ke-Jing Lee, Yeong-Her Wang
Summary: Magnesium zirconate titanate (MZT) thin films prepared using a sol-gel spin-coating method exhibit high sensitivity and repeatability as gas sensors, particularly for detecting NO2. The sensitivity of the MZT thin film to NO2 gas molecules at a working temperature of 150 degrees C was found to be 8.64% for 0.25 ppm and 34.22% for 5 ppm, indicating its potential for gas sensing applications.
Article
Polymer Science
Dan Eduard Mihaiescu, Daniela Istrati, Alina Morosan, Maria Stanca, Bogdan Purcareanu, Rodica Cristescu, Bogdan Stefan Vasile, Roxana Doina Trusca
Summary: This research focuses on the study of cefotaxime absorption and desorption from different functionalized mesoporous silica supports to obtain new materials with sustained release properties. The MCM-41-type nanostructured mesoporous silica support was synthesized and characterized, showing good micro-structured homogeneity, high surface area, and high silanolic activity. Functionalization of the support was conducted to effectively link the cefotaxime compound. The release experiments revealed significant improved release capacity in the functionalized mesoporous silica support.
Article
Engineering, Electrical & Electronic
O. F. Goktas, N. E. Koksal, O. Kaplan, A. Yildiz
Summary: The sol-gel method was used to fabricate Al-doped ZnO (AZO) thin films on p-Si substrates with smooth surfaces and highly oriented crystal structures. The analysis revealed that the AZO/Si heterojunctions exhibited nonideal diode behavior, with the 80 nm thick AZO layer demonstrating good rectifying properties.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2021)
Review
Chemistry, Multidisciplinary
Alexandre F. Carvalho, Bohdan Kulyk, Antonio J. S. Fernandes, Elvira Fortunato, Florinda M. Costa
Summary: As the paradigm of the Internet of Things continues to evolve, there is a growing need for the development of low-cost, environmentally friendly, and sensitive sensors. Mechanical sensors and their applications have been widely studied, with a focus on innovative ways of mechanical actuation for human-machine interaction. Graphene, with its potential scalability and outstanding properties, has been thoroughly researched in the field of mechanical transduction.
ADVANCED MATERIALS
(2022)
Article
Engineering, Chemical
Andreia S. L. Gouveia, Vitor Oliveira, Ana M. Ferraria, Ana M. B. Do Rego, Maria Joao Ferreira, Liliana C. Tome, Amelia Almeida, Isabel M. Marrucho
Summary: The study successfully created microchannels on the surface of PIL-IL materials using femtosecond laser ablation, leading to the improvement of CO2 separation performance of the membranes.
JOURNAL OF MEMBRANE SCIENCE
(2022)
Article
Chemistry, Analytical
Beatriz Jorge Coelho, Bruno Veigas, Luis Bettencourt, Hugo Aguas, Elvira Fortunato, Rodrigo Martins, Pedro Baptista, Rui Igreja
Summary: We introduce a digital microfluidics (DMF) platform for loop-mediated isothermal amplification (LAMP) of DNA, and apply it to real-time amplification for monitoring c-Myc, a cancer biomarker associated with 40% of human tumors. We demonstrate successful manipulation of samples and reagents on the DMF platform, achieving amplification of 90 pg of target DNA in less than one hour. Innovative mixing strategies in DMF, including low frequency AC actuation and back-and-forth droplet motion, improve fluorescence readouts. On-chip sample partitioning and sequential droplet irradiation minimize fluorophore bleaching effects.
Article
Nanoscience & Nanotechnology
Maria Elias Pereira, Jonas Deuermeier, Catia Figueiredo, Angelo Santos, Guilherme Carvalho, Vitor Grade Tavares, Rodrigo Martins, Elvira Fortunato, Pedro Barquinha, Asal Kiazadeh
Summary: This study reports on a thin-film amorphous oxide-based 4x4 1T1M crossbar that addresses the challenges of linear and symmetric synaptic weight update, low cycle-to-cycle and device-to-device variability, and the sneak-path current issue. The results demonstrate a proof-of-concept for a cost-effective, flexible hardware for artificial neural networks.
ADVANCED ELECTRONIC MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Diana Gaspar, Jorge Martins, Jose Tiago Carvalho, Paul Grey, Rogerio Simoes, Elvira Fortunato, Rodrigo Martins, Luis Pereira
Summary: The market for flexible, hybrid, and printed electronic systems is uncertain, but these systems are emerging daily, allowing for devices and systems that can be folded and stored in pockets. Cellulose-based modified nanopapers were developed as a physical support and gate dielectric layer for recyclable field-effect transistors (FETs). Impregnation of the nanopapers with sodium ions enabled low voltage FETs (<3 V), with high mobility (>10 cm2 V-1 s-1), current modulation (>105), and improved dynamic response. These transistors were successfully implemented into simple circuits such as inverters, showing clear discrimination between logic states. Besides improved electrical performance, these devices are a promising alternative for reliable, sustainable, and flexible electronics, even under stress conditions.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Energy & Fuels
Paulo Joaquim Nunes, Rui Francisco Pinto Pereira, Sonia Pereira, Maria Manuela Silva, Elvira Fortunato, Veronica de Zea Bermudez, Mariana Fernandes
Summary: Two di-ureasils with oxyethylene segments were prepared by the sol-gel method, doped with ionic liquid and lithium salt. The resulting films were translucent, flexible, hydrophobic, and had low surface roughness. The optimized sample exhibited good ionic conductivity and was used in prototype electrochromic devices with promising performance.
Review
Medicine, General & Internal
Maria Joao Meneses, Rita Susana Patarrao, Tomas Pinheiro, Ines Coelho, Nuno Carrico, Ana Carolina Marques, Artur Romao, Joao Nabais, Elvira Fortunato, Joao Filipe Raposo, Maria Paula Macedo
Summary: Diabetes is a heterogeneous and multifactorial disease, and besides glycemia and glycated hemoglobin, the evaluation of other biochemical parameters is necessary for better diagnosis and management. Indexes of insulin secretion, sensitivity/resistance, and metabolism have been developed to provide a more comprehensive view of individual metabolic states. New technologies, such as sensors and software applications, have the potential to improve diabetes diagnosis and management, empowering patients and simplifying disease management.
EUROPEAN JOURNAL OF CLINICAL INVESTIGATION
(2023)
Article
Nanoscience & Nanotechnology
Bo He, Gang He, Shanshan Jiang, Jiangwei Liu, Elvira Fortunato, Rodrigo Martins
Summary: Thin-film transistors based on metal oxide semiconductors are widely used in driving low-cost backplanes of active matrix liquid crystal displays. Solution-based 1D nanofiber networks have been proven to be a simpler and higher-throughput approach for transistor fabrication. Double channel heterojunction transistors composed of In2O3 and ZnO layers show high electron mobility and operational stability, which can be optimized by adjusting the stacking order and density of the layers.
ADVANCED ELECTRONIC MATERIALS
(2023)
Article
Biochemistry & Molecular Biology
Ana Sofia Figueiredo, Ana Maria Ferraria, Ana Maria Botelho do Rego, Silvia Monteiro, Ricardo Santos, Miguel Minhalma, Maria Guadalupe Sanchez-Loredo, Rosa Lina Tovar-Tovar, Maria Norberta de Pinho
Summary: The antibacterial properties of cellulose acetate/silver nanoparticles (AgNP) ultrafiltration membranes were studied and the results showed that the distinct features of each side of the membranes, the active and porous layers surfaces, played a role in the antibacterial activity. The composition and structure of the membranes affected the accessibility of the silver to Escherichia coli (E. coli), leading to different levels of growth inhibition. The findings suggest that the membrane design and silver distribution can be optimized to enhance the antibacterial performance.
Article
Biochemistry & Molecular Biology
Rita F. Nunes, Daniel Costa, Ana M. Ferraria, Ana Botelho M. do Rego, Filipa Ribeiro, Angela Martins, Auguste Fernandes
Summary: Due to the need to reduce global CO2 emissions, bio-based fuels are being explored. To reduce oxygen content, bio-oils need to be upgraded through catalytic hydrodeoxygenation (HDO) using bifunctional catalysts with metal and acid sites. Pt-Al2O3 and Ni-Al2O3 catalysts containing heteropolyacids (HPA) were prepared, and their properties were characterized. Ni-based catalysts showed higher conversion and selectivity to deoxygenated compounds, making them the most promising, despite suffering from deactivation over time.
Article
Materials Science, Multidisciplinary
J. Figueira, R. M. Bonito, J. T. Carvalho, E. M. F. Vieira, C. Gaspar, Joana Loureiro, J. H. Correia, E. Fortunato, R. Martins, L. Pereira
Summary: Flexible thermal touch sensors were produced by optimizing ethyl cellulose and graphite flakes inks for screen-printing. The best electrical-TE output combination was achieved by printing two layers of the ink with 20 wt% of graphite on an office paper substrate. The results showed that the screen-printed graphite-based inks are highly suitable for flexible TE sensing applications.
FLEXIBLE AND PRINTED ELECTRONICS
(2023)
Article
Biochemistry & Molecular Biology
Nenad Bundaleski, Carolina F. Adame, Eduardo Alves, Nuno P. Barradas, Maria F. Cerqueira, Jonas Deuermeier, Yorick Delaup, Ana M. Ferraria, Isabel M. M. Ferreira, Holger Neupert, Marcel Himmerlich, Ana Maria M. B. do Rego, Martino Rimoldi, Orlando M. N. D. Teodoro, Mikhail Vasilevskiy, Pedro Costa Pinto
Summary: There has been growing interest in using amorphous carbon thin films with low secondary electron yield (SEY) to reduce electron multipacting in particle accelerators and RF devices. Previous studies have shown that the SEY increases with the amount of hydrogen and is correlated with the Tauc gap. In this study, films produced by magnetron sputtering with varying amounts of hydrogen and deuterium were analyzed, and it was found that the maximal SEY decreases with the fraction of the graphitic phase in the films.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Review
Engineering, Electrical & Electronic
Maria Elias Pereira, Rodrigo Martins, Elvira Fortunato, Pedro Barquinha, Asal Kiazadeh
Summary: Neuromorphic computing is gaining popularity as a replacement for outdated technology in conventional computing systems. Artificial neural networks composed of memristor crossbars in hardware offer power, cost, and area-efficient in-memory computing and storage. Optoelectronic memristors (OEMs) can control resistive switching (RS) through both optical and electronic signals, solving crosstalk issues and providing a high-speed non-destructive method. This review summarizes recent advances in inorganic OEMs, analyzing the device structure and assessing their potential applications in logic gates, artificial neural networks, and artificial visual systems with consideration for their performance.
NEUROMORPHIC COMPUTING AND ENGINEERING
(2023)
Article
Chemistry, Analytical
Maria Joao Oliveira, Soraia Caetano, Ana Dalot, Filipe Sabino, Tomas R. Calmeiro, Elvira Fortunato, Rodrigo Martins, Eulalia Pereira, Miguel Prudencio, Hugh J. Byrne, Ricardo Franco, Hugo Aguas
Summary: Early and accurate detection of pathogenic microorganisms is crucial for diagnosis and patient outcomes. The combination of a polystyrene-based microfluidic device and Surface-Enhanced Raman Spectroscopy shows excellent sensitivity and specificity in detecting malaria. The system can be easily adapted for other pathogens and has the potential for early diagnosis of infectious diseases.
Article
Engineering, Electrical & Electronic
Dorina T. Papanastasiou, Emanuel Carlos, David Munoz-Rojas, Carmen Jimenez, Ana Pimentel, Elvira Fortunato, Rodrigo Martins, Daniel Bellet
Summary: In this study, a low-cost solution-based aluminum oxide (AlOx) coating was used to encapsulate spray-coated silver nanowire (AgNW) networks. The AlOx coating achieved a good compromise between optical transmittance and electrical resistance. It provided a robust protection against corrosion under harsh environmental stress conditions and different morphologies of the AlOx thin film could be obtained for different applications.
ACS APPLIED ELECTRONIC MATERIALS
(2022)
