Combined dip-coating/spin-coating depositions on ceramic honeycomb monoliths for structured catalysts preparation

2019 ◽  
Vol 334 ◽  
pp. 90-95 ◽  
Author(s):  
Riccardo Balzarotti ◽  
Cinzia Cristiani ◽  
Lorraine F. Francis
Cerâmica ◽  
2019 ◽  
Vol 65 (375) ◽  
pp. 477-484 ◽  
Author(s):  
M. P. Madeira ◽  
A. O. Lobo ◽  
B. C. Viana ◽  
E. C. Silva Filho ◽  
J. A. Osajima

Abstract Herein we present a short review of different materials and techniques that have been used for the production of surfaces with self-cleaning and/or antimicrobial properties. From this, it was verified that titanium dioxide was the most frequently used compound to obtain surfaces with these properties; however, other materials such as silica, zinc and silver have also been used for this purpose. The spin-coating and dip-coating techniques were the most used techniques, and the bacteria Staphylococcus aureus and Escherichia coli were the most used in the antimicrobial assays. The analyzed studies showed that it is possible to obtain surfaces with both self-cleaning and/or antimicrobial properties, as well as with photocatalytic activity. Regarding possible applications, it is possible to highlight the interest in the production of glass and medical devices with self-cleaning and/or antimicrobial action.


2004 ◽  
Vol 848 ◽  
Author(s):  
Andrew W. Jackson ◽  
Andrew L. Hector

ABSTRACTThere is an increasing interest in sol-gel synthesis of nitrides. The ability to deposit films of these materials by dip- or spin-coating will increase the range of applications in which they are viable and is an important step toward general sol-gel processing of nitride materials.With transition metals, the ammono based analogue of the well established alkoxy route to gels is inherently difficult to control. Due to the basicity of the system, the overwhelming tendency is of the starting materials to favour particle growth which results in a precipitate rather than a stable emulsion, unless both environment and synthetic pathway are carefully controlled. Hence reports to date of sol-gel routes to nitrides describe production of powders. We report work on a sol-gel route to titanium nitride with the ammonolysis of titanium amides controlled by temperature and chemical moderators, resulting in stable emulsions useful for dip-coating.


2018 ◽  
Vol 22 (suppl 1) ◽  
Author(s):  
Andreza Menezes Lima ◽  
Géssica Seara Faria ◽  
Stefania Nardecchia ◽  
Leila Rosa de Oliveira Cruz ◽  
Mariana de Mattos Vieira Mello Souza ◽  
...  
Keyword(s):  

RESUMO Dispersões de óxido de grafeno (GO) e de óxido de grafeno reduzido (rGO) foram produzidas, respectivamente, por via química através do método de Hummers modificado e por redução do GO com adição de polímero PSS (poli (4-estirenosulfonato de sódio)) e ácido ascórbico. Amostras de GO e rGO/PSS foram caracterizadas pelas seguintes técnicas: microscopia óptica, microscopia eletrônica de varredura (MEV), espectroscopia Raman e espectroscopia de fotoelétrons excitados por raios X (XPS). A partir das dispersões foram depositados filmes finos em substratos de vidro pelos seguintes métodos: spray, dip coating e spin coating. Os filmes produzidos foram, em seguida, tratados termicamente para melhoria da aderência nos substratos e, especificamente para os filmes de GO, para redução, de modo a formar o óxido de grafeno reduzido termicamente (trGO). Os filmes foram caracterizados quanto a espessura, morfologia, transmitância e resistência de folha. Por meio das caracterizações realizadas a partir das dispersões foi possível observar folhas de grafeno pela microscopia óptica, indicando o sucesso do método de produção empregado; por meio do XPS, determinou-se a composição das amostras de GO e rGO e confirmou-se que a redução com ácido ascórbico foi efetiva; as transmitâncias obtidas mostraram-se dentro da faixa indicada para aplicação e as resistividades de algumas amostras, alcançaram valores próximos a de materiais tradicionalmente aplicados como filmes transparentes e condutores.


2007 ◽  
Author(s):  
Xiliang He ◽  
Jiehua Wu ◽  
Xiangdong Gao ◽  
Lingnan Wu ◽  
Xiaomin Li

Sensors ◽  
2018 ◽  
Vol 18 (11) ◽  
pp. 3942 ◽  
Author(s):  
Tomasz Wasilewski ◽  
Bartosz Szulczyński ◽  
Wojciech Kamysz ◽  
Jacek Gębicki ◽  
Jacek Namieśnik

The quartz-crystal microbalance is a sensitive and universal tool for measuring concentrations of various gases in the air. Biochemical functionalization of the QCM electrode allows a label-free detection of specific molecular interactions with high sensitivity and specificity. In addition, it enables a real-time determination of its kinetic rates and affinity constants. This makes QCM a versatile bioanalytical screening tool for various applications, with surface modifications ranging from the detection of single molecular monolayers to whole cells. Various types of biomaterials, including peptides mapping the binding sites of olfactory receptors, can be deposited as a sensitive element on the surface of the electrodes. One of key ways to ensure the sensitivity and accuracy of the sensor is provided by application of an optimal and repeatable method of immobilization. Therefore, effective sensors operation requires development of an optimal method of deposition. This paper reviews popular techniques (drop-casting, spin-coating, dip-coating) for coating peptides on piezoelectric crystals surface. Peptide (LEKKKKDC-NH2) derived from an aldehyde binding site in the HarmOBP7 protein was synthesized and used as a sensing material for the biosensor. The degree of deposition of the sensitive layer was monitoring by variations in the sensors frequency. The highest mass threshold for QCM measurements for peptides was approximately 16.43 µg·mm−2 for spin coating method. Developed sensor exhibited repeatable response to acetaldehyde. Moreover, responses to toluene was observed to evaluate sensors specificity. Calibration curves of the three sensors showed good determination coefficients (R2 > 0.99) for drop casting and dip coating and 0.97 for the spin-coating method. Sensors sensitivity vs. acetaldehyde were significantly higher for the dip-coating and drop-casting methods and lower for spin-coating one.


2015 ◽  
Vol 1767 ◽  
pp. 49-55
Author(s):  
Alma B. Medrano-Solís ◽  
María E. Nicho-Díaz ◽  
Hailin Hu

ABSTRACTThe polyaniline (PANI) and regioregular poly(3-hexylthiophene) (P3HTr) are polymers synthesized easily, can be deposited as a film by various techniques, are materials that exhibit a variety of colors to go through oxidation processes and reduction by applying an external potential, both polymers have an immediate response rate of color. The electrochemical behavior of the PANI and P3HTr is complementary, that is, if a positive potential to the device is applied, the PANI film is oxidized while the P3HTr film is reduced, on the other hand, if a negative potential is applied, the PANI film is reduced while the P3HTr film is oxidized. Both films in its redox process are clarified and obscured at the same time, this color change provides a significant difference in optical transmittance on a dual electrochromic device (DED's).In this research, regioregular poly(3-hexylthiophene) was synthesized and characterized, films were deposited by spin-coating and dip-coating techniques. Polyaniline films were deposited by chemical bath and spin-coating techniques. Dual electrochromic devices based on P3HTr and PANI were prepared. The devices were studied by UV-vis spectroscopy at three different voltages: 1.4 V, 0 V and -1.4 V, optical kinetic tests were also performed at 550 nm applying a positive potential (1.4 V) and negative (-1.4 V). The results indicated the wavelength where both (PANI and P3HT) reach the greatest difference in transmittance. The influence of deposit type of polymer films on electrochromic response was determined.


2014 ◽  
Vol 71 (3) ◽  
pp. 437-446 ◽  
Author(s):  
Milda Malakauskaite-Petruleviciene ◽  
Zivile Stankeviciute ◽  
Aldona Beganskiene ◽  
Aivaras Kareiva

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