The enhanced photocatalytic activity and self-cleaning properties of mesoporous SiO2 coated Cu-Bi2O3 thin films

The pure TiO2and SnO2-TiO2thin films on glass substrate were fabricated using a sol-gel dip coating technique. The thin films were annealed at the temperature of 700 °C for 2 h with the heating rate of 10 °C/min. The microstructures of the fabricated thin films were characterized by SEM and XRD techniques. The photocatalytic activities of the thin films were also tested by the degradation of methylene blue (MB) solution under UV irradiation. Finally, hydrophilic or self-cleaning properties of thin films were evaluated by measuring the contact angle of water droplet on the thin films with and without UV irradiation. It was found that 1 %mol SnO2-TiO2thin films shows the highest of photocatalytic activity and provide the most self-cleaning properties.

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Transparent Photocatalytic Thin Films on Flexible Polymer Substrates

Materials ◽

10.3390/ma11101945 ◽

2018 ◽

Vol 11 (10) ◽

pp. 1945 ◽

Cited By ~ 7

Author(s):

Nives Vodišek ◽

Andraž Šuligoj ◽

Dorota Korte ◽

Urška Lavrenčič Štangar

Keyword(s):

Thin Films ◽

Photocatalytic Activity ◽

Vinylidene Fluoride ◽

Mechanical Stability ◽

Light Exposure ◽

Beam Deflection ◽

Polymer Substrates ◽

Flexible Polymer ◽

Self Cleaning ◽

Photocatalytic Films

Self-cleaning and/or photocatalytic films on polymer substrates have found numerous applications during the past decades. However, the common demand for high-temperature post synthesis treatment limits the application to temperature resistant substrates only. Herein, we prepared self-cleaning photocatalytic films on four thermosensitive polymeric substrates: polyvinyl chloride (PVC), polymethyl methacrylate (PMMA), and acryl coated polyester (PES) fabric (D2) with poly(vinylidene fluoride) (PVDF) containing lacquer (D1). TiO2 was prepared via a low-temperature sol-gel process using titanium(IV) isopropoxide and zirconium(IV) butoxide as precursors with various loading levels of Zr; 0, 5, 10, and 20 mol.%, and deposited on the substrates by using a SiO2 binder in form of thin films (ca. 200 nm thick) via dip-coating. The films were characterized by SEM, hardness test, UV-Vis, photothermal beam deflection spectroscopy, and IR spectroscopy, while photocatalytic activity was measured by the fluorescence-based method of the terephthalic acid probe and wetting by contact angle measurements. Films containing 10 mol.% of Zr showed the best compromise regarding photocatalytic activity and mechanical stability while from substrates point of view PVC performed the best, followed by PMMA, D1, and D2. The beneficial role of SiO2 binder was not only guaranteeing excellent mechanical stability, but also to prevent the D1 polymer from deterioration; the latter was found to be labile to long-term solar-light exposure due to degradation of the top PVDF layer.

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Thickness Effect on Photocatalytic Activity of TiO2 Thin Films Fabricated by Ultrasonic Spray Pyrolysis

Catalysts ◽

10.3390/catal10091058 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1058

Author(s):

Ibrahim Dundar ◽

Arvo Mere ◽

Valdek Mikli ◽

Malle Krunks ◽

Ilona Oja Acik

Keyword(s):

Thin Films ◽

Photocatalytic Activity ◽

Film Thickness ◽

Stearic Acid ◽

Spray Pyrolysis ◽

Ultrasonic Spray Pyrolysis ◽

Tio2 Films ◽

Tio2 Thin Films ◽

Ultrasonic Spray ◽

Self Cleaning

In this study, TiO2 thin films were deposited by ultrasonic spray pyrolysis from solutions with concentrations of 0.1 and 0.2 M. The deposition temperature was adjusted at 350 °C and all samples were annealed at 500 °C for 1 h in air. The thickness of TiO2 films was changed in the range of 50 to ca. 800 nm by varying the number of spray cycles from 1 to 21 and the solution concentration. The results showed that the mean crystallite size of the anatase structure, the surface roughness, and light absorption increased with the film thickness. The effect of film thickness on the photocatalytic activity was investigated with the photodegradation of stearic acid under UV-A irradiation. The optimal thickness of TiO2 films fabricated by ultrasonic spray pyrolysis for photocatalytic self-cleaning applications was in the range of 170–230 nm, indicating a ca. 2.6 times-higher photocatalytic self-cleaning activity compared to the reference sample, Pilkington ActivTM. The photocatalytic results showed that the 190 nm-thick TiO2 film deposited from the 0.1 M solution applying seven spray cycles exhibited the finest grain structure and maximum photocatalytic activity, leading to 94% of stearic acid degradation in 180 min under UV-A light with the reaction rate constant k = 0.01648 min−1.

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Rational Design and Construction of Well-Organized Macro-Mesoporous SiO2/TiO2 Nanostructure toward Robust High-Performance Self-Cleaning Antireflective Thin Films

ACS Applied Materials & Interfaces ◽

10.1021/acsami.7b04140 ◽

2017 ◽

Vol 9 (20) ◽

pp. 17466-17475 ◽

Cited By ~ 21

Author(s):

Binbin Jin ◽

Junhui He ◽

Lin Yao ◽

Yue Zhang ◽

Jing Li

Keyword(s):

Thin Films ◽

High Performance ◽

Rational Design ◽

Mesoporous Sio2 ◽

Self Cleaning ◽

Tio2 Nanostructure ◽

Design And Construction

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Preparation of mesoporous SiO2/Bi2O3/TiO2 superhydrophilic thin films and their surface self-cleaning properties

RSC Advances ◽

10.1039/c6ra26078k ◽

2017 ◽

Vol 7 (4) ◽

pp. 1966-1974 ◽

Cited By ~ 19

Author(s):

Zhaogao Bai ◽

Yun Hu ◽

Shuqin Yan ◽

Wenjie Shan ◽

Chaohai Wei

Keyword(s):

Thin Films ◽

Spin Coating ◽

Sol Gel ◽

Spin Coating Method ◽

Glass Slides ◽

Coating Method ◽

Mesoporous Sio2 ◽

Self Cleaning

Mesoporous SiO2/Bi2O3/TiO2 triple-layered thin films were prepared on glass slides using a simple sol–gel/spin-coating method.

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Photocatalytic degradation of methylene blue from aqueous solutions using nanopillars-TiO2 thin films: Batch reactor studies

Science Vision ◽

10.33493/scivis.18.03.01 ◽

2018 ◽

Vol 18 (3) ◽

pp. 81-91 ◽

Cited By ~ 1

Author(s):

C. Lalhriatpuia

Keyword(s):

Thin Films ◽

Methylene Blue ◽

Photocatalytic Activity ◽

Organic Carbon ◽

Photocatalytic Degradation ◽

Batch Reactor ◽

Tio2 Thin Films ◽

Initial Concentration ◽

Bet Specific Surface Area ◽

Interfering Ions

Nanopillars-TiO2 thin films was obtained on a borosilicate glass substrate with (S1) and without (S2) polyethylene glycol as template. The photocatalytic behaviour of S1 and S2 thin films was assessed inthe degradation of methylene blue (MB) dye from aqueous solution under batch reactor operations. The thin films were characterized by the SEM, XRD, FTIR and AFM analytical methods. BET specific surface area and pore sizes were also obtained. The XRD data confirmed that the TiO2 particles are in its anatase mineral phase. The SEM and AFM images indicated the catalyst is composed with nanosized pillars of TiO2, evenly distributed on the surface of the substrate. The BET specific surface area and pore sizes of S1 and S2 catalyst were found to be 5.217 and 1.420 m2/g and 7.77 and 4.16 nm respectively. The photocatalytic degradation of MB was well studied at wide range of physico-chemical parameters. The effect of solution pH (pH 4.0 to 10.0) and MB initial concentration (1.0 to 10.0 mg/L) was extensively studied and the effect of several interfering ions, i.e., cadmium nitrate, copper sulfate, zinc chloride, sodium chloride, sodium nitrate, sodium nitrite, glycine, oxalic acid and EDTA in the photocatalytic degradation of MB was demonstrated. The maximum percent removal of MB was observed at pH 8.0 beyond which it started decreasing and a low initial concentration of the pollutant highly favoured the photocatalytic degradation using thin films and the presence of several interfering ions diminished the photocatalytic activity of thin films to some extent. The overall photocatalytic activity was in the order: S2 > S1 > UV. The photocatalytic degradation of MB was followed the pseudo-first-order rate kinetics. The mineralization of MB was studied with total organic carbon measurement using the TOC (total organic carbon) analysis.

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STRUCTURAL, OPTICAL PROPERTIES AND PHOTOCATALYTIC ACTIVITY OF NANOCRYSTALLINE TiO2 THIN FILMS DEPOSITED BY SOL-GEL SPIN COATING

i-manager s Journal on Material Science ◽

10.26634/jms.7.1.15719 ◽

2019 ◽

Vol 7 (1) ◽

pp. 28

Author(s):

KOMARAIAH DURGAM ◽

RADHA EPPA ◽

REDDY M. V. RAMANA ◽

KUMAR J. SIVA ◽

R. SAYANNA ◽

...

Keyword(s):

Thin Films ◽

Optical Properties ◽

Photocatalytic Activity ◽

Spin Coating ◽

Sol Gel ◽

Tio2 Thin Films ◽

Nanocrystalline Tio2

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Use of Nanopillars-TiO2 Thin Films in the Photocatalytic Degradation of Bromophenol Blue from Aqueous Solution

Science & Technology Journal ◽

10.22232/stj.2018.06.01.03 ◽

2018 ◽

Vol 6 (1) ◽

pp. 22-30

Author(s):

C. Lalhriatpuia ◽

◽

Thanhming liana ◽

K. Vanlaldinpuia

Keyword(s):

Thin Films ◽

Aqueous Solution ◽

Photocatalytic Activity ◽

Photocatalytic Degradation ◽

Batch Reactor ◽

Bromophenol Blue ◽

Tio2 Thin Films ◽

Initial Concentration ◽

Bet Specific Surface Area ◽

Interfering Ions

The photocatalytic activity of Nanopillars-TiO2 thin films was assessed in the degradation of Bromophenol blue (BPB) dye from aqueous solution under batch reactor operations. The thin films were characterized by the XRD, SEM and AFM analytical methods. BET specific surface area and pore sizes were also obtained. The XRD data showed anatase phase of TiO2 particles with average particle size of 25.4 and 21.9 nm, for S1 and S2 catalysts respectively. The SEM and AFM images indicated the catalyst composed with Nanosized pillars of TiO2, evenly distributed on the surface of the substrate. The average height of the pillars was found to be 180 and 40 nm respectively for the S1 and S2 catalyst. The BET specific surface area and pore sizes of S1 and S2 catalyst were found to be 5.217 and 1.420 m2/g and 7.77 and 4.16 nm respectively. The photocatalytic degradation of BPB using the UV light was studied at wide range of physico-chemical parametric studies to determine the mechanism of degradation as well as the practical applicability of the technique. The batch reactor operations were conducted at varied pH (pH 4.0 to 10.0), BPB initial concentration (1.0 to 20.0 mg/L) and presence of several interfering ions, i.e., cadmium nitrate, copper sulfate, zinc chloride, sodium chloride, sodium nitrate, sodium nitrite, glycine, oxalic acid and EDTA in the photocatalytic degradation of BPB. The maximum percent removal of BPB was observed at pH 6.0 and a low initial concentration of the pollutant highly favours the photocatalytic degradation using thin films. The presence of several interfering ions suppressed the photocatalytic activity of thin films to some extent. The time dependence photocatalytic degradation of BPB was demonstrated with the pseudo-first-order rate kinetics. Study was further extended with total organic carbon measurement using the TOC (Total Organic Carbon) analysis. This demonstrated an apparent mineralization of BPB from aqueous solutions.

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