scholarly journals Preparation and characterization of protective self-cleaning TiO2/kaolin composite coating

2018 ◽  
Vol 68 (331) ◽  
pp. 163
Author(s):  
V. Jovanov ◽  
V. Zečević ◽  
T. Vulić ◽  
J. Ranogajec ◽  
E. Fidanchevska
Keyword(s):  
Photocatalytic Activity ◽  
Composite Coating ◽  
Building Materials ◽  
Support Surface ◽  
Tio2 Content ◽  
Cleaning Efficiency ◽  
Before And After ◽  
Self Cleaning ◽  
Highly Porous

The application of self-cleaning coatings presents one of the most effective ways to protect the surfaces of the building materials. The effect of TiO2/kaolin based coatings applied to three types of substrates: non-porous, porous and highly porous, was investigated. Mechanical activation was applied for the impregnation of the active TiO2 component (in content of 3 and 10 wt. %) into the kaolin support. Surface properties (roughness, hydrophilicity and micro-hardness) and functional properties (photocatalytic activity and self-cleaning efficiency) were studied in order to define the optimal formulation of the applied coatings. The effect of the photocatalytic behavior of the coated substrates in terms of self-cleaning ability was assessed by the photodegradation of Rhodamine B, performed before and after durability tests. The results obtained in this paper showed that photocatalytic activity of the TiO2/kaolin composite coating generally depends on the procedure of TiO2 impregnation into the kaolin clay and the loaded TiO2 content.

scholarly journals Electrical properties and microstructure fractal analysis of magnesium-modified aluminium-silicate ceramics

2011 ◽  
Vol 43 (2) ◽  
pp. 193-204 ◽  
Author(s):  
J. Purenovic ◽  
V.V. Mitic ◽  
Lj. Kocic ◽  
V.B. Pavlovic ◽  
V. Paunovic ◽  
...  
Keyword(s):  
Fractal Analysis ◽  
Sintering Temperature ◽  
Electrical Characterization ◽  
Porous Ceramics ◽  
Before And After ◽  
High Degree ◽  
Highly Porous ◽  
Aluminium Silicate

The addition of Mg2(NO)3 and some active additives, composed of Al salts, to the mixtures of kaolinite and bentonite can provide clay compositions which, after sintering at high temperatures, produce very porous ceramics with microcrystalline and amorphous regions and highly developed metalized surfaces (mainly with magnesium surplus). Characterization of sintered samples was done before and after treatment in ?synthetic water?, i.e. in aqueous solution of arsenic-salt. Microstructure investigations have revealed non-uniform and highly porous structure with broad distribution of grain size, specifically shaped grains and high degree of agglomeration. Electrical characterization was estimated by determining dielectric constant and electrical resistivity in function of active additives amount and sintering temperature. Fractal analysis has included determination of grain contour fractal dimension.

scholarly journals SELF-CLEANING GLASS BASED ON ACID-TREATED TiO2 FILMS WITH PALMITIC ACID AS MODEL POLLUTANT

2010 ◽  
Vol 8 (2) ◽  
pp. 200-206
Author(s):  
Nurul Hidayat Aprilita ◽  
Indriana Kartini ◽  
Sofy Herawati Ratnaningtyas
Keyword(s):  
Thin Film ◽  
Photocatalytic Activity ◽  
Palmitic Acid ◽  
Uv Radiation ◽  
Acid Treatment ◽  
Tio2 Films ◽  
Sem Images ◽  
Self Cleaning ◽  
Radiation Time

Preparation and characterization of self-cleaning glass based on acid-treated TiO2 films as well as evaluation on their self-cleaning properties have been carried out. Palmitic acid photodegradation was used as model pollutant. Acid-treated TiO2 powders were deposited on glass surface by using spraying technique. The XRD results showed that acid-treated TiO2 film exhibited decreased anatase crystalline size. The corresponding SEM images showed porous surface morphology. Layer densification was observed as the film thickness increased. TiO2 photocatalytic activity increased as the length of UV radiation increased. Best results were obtained at experimental condition of 35 hours UV radiation time. It is also observed that the thickness of TiO2 layers influenced the efficiency of palmitic acid photodegradation. The film with 1.661 µm thick TiO2 layers and 6.933 mg weight (0.7164 mg/cm2) could degrade 97.54 % mg palmitic acid/cm2 thin film.   Keywords: TiO2 films, acid treatment, self-cleaning glass

scholarly journals Photocatalytic Activity of TiO2/AuNRs–SiO2 Nanocomposites Applied to Building Materials

Coatings ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 296 ◽  
Author(s):  
Alessandra Truppi ◽  
Manuel Luna ◽  
Francesca Petronella ◽  
Aurelia Falcicchio ◽  
Cinzia Giannini ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Photocatalytic Oxidation ◽  
Building Materials ◽  
Low Cost ◽  
Solar Light ◽  
Simulated Solar Light ◽  
Direct Exposure ◽  
Carbon Soot ◽  
Sio2 Nanocomposites ◽  
Self Cleaning

In this work, the self-cleaning and photocatalytic properties of mesoporous TiO2/AuNRs-SiO2 composites (namely UCA–TiO2Au) prepared by a simple and low-cost technique were investigated toward application in building materials. Mesoporous photocatalytic nanocomposites coating the surface of stone and other building materials are a very promising approach to address relevant questions connected with the increasing atmospheric pollution. We tested three types of preformed TiO2/AuNRs nanostructures in order to evaluate the effect of AuNRs on the photocatalytic activity of resulting coatings deposited on the surface of a popular building limestone. The resulting nanocomposites provide crack-free surface coatings on limestone, effective adhesion, improve the stone mechanical properties and impart hydrophobic and self-cleaning properties. Photocatalytic characterization involved the degradation of a target compound (Methylene blue; MB) under direct exposure to simulated solar light using TiO2 P25 Evonik (TiO2 P25) as a reference material. Moreover, these coatings upon irradiation by simulated solar light were successfully employed for the photocatalytic oxidation of carbon soot. The experimental results revealed that UCA–TiO2Au samples are the best performing coating in both MB bleaching and soot degradation.

scholarly journals Novel photocatalytic coating on façade paints: Functional properties and durability

2018 ◽  
pp. 181-191
Author(s):  
Tatjana Vulic ◽  
Snezana Vucetic ◽  
Bojan Miljevic ◽  
Jonjaua Ranogajec
Keyword(s):  
Photocatalytic Activity ◽  
Functional Properties ◽  
Building Materials ◽  
Environmental Pollutants ◽  
Weather Conditions ◽  
Negative Influence ◽  
The Self ◽  
Before And After ◽  
Materials Used ◽  
Double Hydroxides

The negative influence of the environmental pollutants on building materials used for fa?ades could be minimized by applying protective photocatalytic coatings with selfcleaning properties. Novel inorganic-inorganic nanocomposite photocatalytic coating based on TiO2/Zn-Al layered double hydroxides (LDHs) was applied on commercial fa?ade paint and the functional properties (photocatalytic activity and surface properties) were studied before and after durability tests towards the adhesion of the coating. The results showed that the TiO2/ZnAl LDH based coating did not influence esthetic appearance, surface roughness and microhardness of the fa?ade paints. The coating demonstrated a significant photocatalytic activity and the photo-induced hydrophilicity, enabling the self-cleaning effect. The study of the influence of temperature and relative humidity on photocatalytic activity indicated that optimal weather conditions for the application of coating precursors onto the fa?ade paints are in the spring and in autumn seasons.

scholarly journals Characterization of photocatalytically active coatings based on TiO2/Zn-Al layered double hydroxide on ceramic tiles

2013 ◽  
pp. 181-190 ◽  
Author(s):  
Tatjana Vulic ◽  
Ognjen Rudic ◽  
Jonjaua Ranogajec
Keyword(s):  
Photocatalytic Activity ◽  
Molecular Mass ◽  
Point Of View ◽  
The Self ◽  
Ceramic Tiles ◽  
Peg 4000 ◽  
Degradation Reaction ◽  
Self Cleaning ◽  
Double Hydroxide

The self-cleaning function (photocatalytic activity and surface hydrophilicity/hydrophobicity) is of great importance for ceramic tiles from both economic and environmental point of view. This research is focused on the preparation of suitable photocatalytic suspensions studying the influence of the photocatalyst powder amount and the molecular mass of polyethylene glycol (PEG) on the self-cleaning properties of the suspensions deposited on the ceramic tile surface. Photocatalysts based on Zn-Al double layered hydroxides with TiO2 as active component, were synthesized and used for the preparation of the suspensions. The coated tiles prepared using smaller photocatalyst amount and the highest investigated molecular mass of PEG (PEG 4000) showed the highest photocatalytic activity in the Rhodamine B degradation reaction, as well as the appropriate surface properties.

An Electron Microscope Study of Interdiffusion and Compound Formation in Ta-Au Thin Films

1973 ◽  
Vol 31 ◽  
pp. 32-33 ◽  
Author(s):  
T. C. Tisone ◽  
S. Lau
Keyword(s):  
Electron Microscope ◽  
Electron Microscope Study ◽  
Thermally Grown Oxide ◽  
Ion Milling ◽  
Compound Formation ◽  
Technology Application ◽  
Transmission Electron ◽  
Before And After ◽  
Au Thin Films

In a study of the properties of a Ta-Au metallization system for thin film technology application, the interdiffusion between Ta(bcc)-Au, βTa-Au and Ta2M-Au films was studied. Considered here is a discussion of the use of the transmission electron microscope(TEM) in the identification of phases formed and characterization of the film microstructures before and after annealing.The films were deposited by sputtering onto silicon wafers with 5000 Å of thermally grown oxide. The film thicknesses were 2000 Å of Ta and 2000 Å of Au. Samples for TEM observation were prepared by ultrasonically cutting 3mm disks from the wafers. The disks were first chemically etched from the silicon side using a HNO3 :HF(19:5) solution followed by ion milling to perforation of the Au side.

scholarly journals Thermal Characterization of Recycled Materials for Building Insulation

Energies ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3564
Author(s):  
Arnas Majumder ◽  
Laura Canale ◽  
Costantino Carlo Mastino ◽  
Antonio Pacitto ◽  
Andrea Frattolillo ◽  
...  
Keyword(s):  
Environmental Impact ◽  
Environmental Sustainability ◽  
Building Materials ◽  
Raw Materials ◽  
Natural Fibers ◽  
Thermal Characterization ◽  
Recycled Materials ◽  
Building Insulation ◽  
Operational Phase

The building sector is known to have a significant environmental impact, considering that it is the largest contributor to global greenhouse gas emissions of around 36% and is also responsible for about 40% of global energy consumption. Of this, about 50% takes place during the building operational phase, while around 10–20% is consumed in materials manufacturing, transport and building construction, maintenance, and demolition. Increasing the necessity of reducing the environmental impact of buildings has led to enhancing not only the thermal performances of building materials, but also the environmental sustainability of their production chains and waste prevention. As a consequence, novel thermo-insulating building materials or products have been developed by using both locally produced natural and waste/recycled materials that are able to provide good thermal performances while also having a lower environmental impact. In this context, the aim of this work is to provide a detailed analysis for the thermal characterization of recycled materials for building insulation. To this end, the thermal behavior of different materials representing industrial residual or wastes collected or recycled using Sardinian zero-km locally available raw materials was investigated, namely: (1) plasters with recycled materials; (2) plasters with natural fibers; and (3) building insulation materials with natural fibers. Results indicate that the investigated materials were able to improve not only the energy performances but also the environmental comfort in both new and in existing buildings. In particular, plasters and mortars with recycled materials and with natural fibers showed, respectively, values of thermal conductivity (at 20 °C) lower than 0.475 and 0.272 W/(m⋅K), while that of building materials with natural fibers was always lower than 0.162 W/(m⋅K) with lower values for compounds with recycled materials (0.107 W/(m⋅K)). Further developments are underway to analyze the mechanical properties of these materials.

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