Thermal Decomposition of Some Sol-Gel Precursors for Mesoporous TiO2-Based Thin Films for Chemorezistive Environmental Sensors

This paper presents a comparative study on the thermal decomposition in air and FTIR analyses of complex sol-gel precursors used for the deposition of three titania based mesoporous thin films: TiO2, Nb-doped TiO2 and carbon nanotubes (MWCNT)-doped TiO2. The effect of doping with Nb or adding MWCNT on the thermal decomposition of titanium isopropoxide-based precursor and crystallization of TiO2 was investigated through thermogravimetric analysis (TGA), differential thermal analysis (DTA), and Fourier Transform Infrared (FTIR) data. TG-DTA results showed two main exothermic peaks were observed in all samples for the temperature range 280-300 oC and 429-444 oC, corresponding to isopropoxide oxidative decomposition and anatase crystallization. In case of Nb doped TiO2 an oxidative decomposition of Nb ethoxide appears at 198 �C. The acidified MWCNT are thermally stable up to 500�C. Doping TiO2 causes peaks shift to higher temperatures. Also, the effect of heating rate on thermal decomposition for precursors was studied. FTIR analyses were conducted on precursor systems thermally treated at different temperature to track the chemical transformations during the films formation.

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Surfactant Effect on the Synthesis of Mesoporous TiO2-SiO2 Coatings Using Sol-Gel Technology

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.762.263 ◽

2018 ◽

Vol 762 ◽

pp. 263-267

Author(s):

Margarita Karpe

Keyword(s):

Thin Films ◽

Sol Gel ◽

Mesoporous Structure ◽

Titanium Isopropoxide ◽

Water Contact ◽

Separation Membranes ◽

Mesoporous Thin Films ◽

Potential Applications ◽

Triblock Copolymer Surfactant ◽

Xrd Patterns

The aim of the research was to develop the area of mesoporous thin films of a binary TiO2–SiO2 system. Sol was synthesized from tetraethylorthosilicate as the silica source and titanium isopropoxide solution as the TiO2 source, while triblock copolymer surfactant (Pluronic F 127 (10% solution in water, (P))) was used as the mesostructure-directing agent. In this paper we present sol-gel obtained TiO2–SiO2 with a mesoporous structure. The effects of added titanium on the mesostructure and on the porosity are presented and discussed. Four different molar percentage ratios of Ti: Si were used for the synthesis of mixed TiO2–SiO2 mesoporous thin films on glass substrate. The mesoporous structure of thin films was characterized by X-ray diffraction (XRD) patterns, atomic force microscopy (AFM), scanning electron microscopy (SEM) and the water contact angle. These mesoporous TiO2–SiO2 thin films could have many potential applications in many areas such as separation membranes, catalysis, optics, and self-cleaning surfaces.

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Spectroelectrochemical Investigations of Cation-Insertion Reactions at Sol−Gel-Derived Nanostructured, Mesoporous Thin Films of Manganese Oxide†

The Journal of Physical Chemistry B ◽

10.1021/jp0112830 ◽

2001 ◽

Vol 105 (37) ◽

pp. 8712-8717 ◽

Cited By ~ 42

Author(s):

Jeffrey W. Long ◽

Lala R. Qadir ◽

Rhonda M. Stroud ◽

Debra R. Rolison

Keyword(s):

Thin Films ◽

Manganese Oxide ◽

Sol Gel ◽

Insertion Reactions ◽

Mesoporous Thin Films

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Visible light induced cell damage of Gram positive bacteria by N-doped TiO2 mesoporous thin films

Thin Solid Films ◽

10.1016/j.tsf.2012.12.056 ◽

2013 ◽

Vol 531 ◽

pp. 559-565 ◽

Cited By ~ 19

Author(s):

S.S. Soni ◽

G.S. Dave ◽

M.J. Henderson ◽

A. Gibaud

Keyword(s):

Thin Films ◽

Visible Light ◽

Cell Damage ◽

Gram Positive ◽

Doped Tio2 ◽

Gram Positive Bacteria ◽

Mesoporous Thin Films

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Structural, magnetic and optical properties of Ni-doped TiO2 thin films deposited on silicon(100) substrates by sol–gel process

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2013.07.105 ◽

2013 ◽

Vol 581 ◽

pp. 318-323 ◽

Cited By ~ 46

Author(s):

Jianjun Tian ◽

Huiping Gao ◽

Hongmei Deng ◽

Lin Sun ◽

Hui Kong ◽

...

Keyword(s):

Thin Films ◽

Optical Properties ◽

Sol Gel ◽

Tio2 Thin Films ◽

Doped Tio2 ◽

Sol Gel Process

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Sol–gel synthesis, characterization and optical properties of mercury-doped TiO2 thin films deposited on ITO glass substrates

Applied Surface Science ◽

10.1016/j.apsusc.2011.05.107 ◽

2011 ◽

Vol 257 (21) ◽

pp. 9103-9109 ◽

Cited By ~ 26

Author(s):

R. Mechiakh ◽

N. Ben Sedrine ◽

R. Chtourou

Keyword(s):

Thin Films ◽

Optical Properties ◽

Sol Gel ◽

Tio2 Thin Films ◽

Doped Tio2 ◽

Glass Substrates ◽

Ito Glass ◽

Sol Gel Synthesis

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Thermoreactivity of Sol-Gel Precursor for ZnO-Based Thin Films

Materials Science Forum ◽

10.4028/www.scientific.net/msf.514-516.73 ◽

2006 ◽

Vol 514-516 ◽

pp. 73-77 ◽

Cited By ~ 2

Author(s):

Viorica Muşat ◽

Paula M. Vilarinho ◽

Regina da Conceição Corredeira Monteiro ◽

Elvira Fortunato ◽

E. Segal

Keyword(s):

Differential Equation ◽

Thin Films ◽

Activation Energy ◽

Thermal Decomposition ◽

Organic Compounds ◽

Sol Gel ◽

Hexagonal Lattice ◽

Kinetic Investigation ◽

Temperature Range ◽

Carbonate Hydroxide

The thermoreactivity of a zinc acetate non-alkoxide solution used for the preparation of ZnO-based thin films was investigated in the temperature range 20-600°C by TG-DTA, XRD and SEM data. We found that the formation in air of ZnO crystallites from the sol-gel precursor occurs above 150°C simultaneously with the decomposition of an intermediary compound, most probably carbonate hydroxide (sclarite and/or hydrozincite). At 200 °C, the crystalline structure is well defined in terms of ZnO hexagonal lattice parameters, although residual organic compounds and water were not yet fully removed and an amorphous phase coexists. A kinetic investigation on the thermal decomposition of sol-gel precursor from DTA data using Kissinger differential equation is also presented. Apparent activation energy values of about. 100 kJ mol-1 corresponding to the nonisothermal decomposition of solid precursors in the temperature range 170-250oC have been found.

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Synthesis and characterization of Fe(III)-doped ceramic membranes of titanium dioxide and its application in photoelectrocatalysis of a textile dye

Eclética Química Journal ◽

10.26850/1678-4618eqj.v36.1.2011.p18-37 ◽

2017 ◽

Vol 36 (1) ◽

pp. 18

Author(s):

Emanuel C. Rodrigues ◽

Layciane A. Soares ◽

Marco A. Modenes Jr. ◽

Jeosadaque J. Sene ◽

Gilbert Bannach ◽

...

Keyword(s):

Thin Film ◽

Sol Gel ◽

Ceramic Membranes ◽

Titanium Isopropoxide ◽

Textile Dye ◽

Doped Tio2 ◽

Precursor Material ◽

Thin Film Electrodes ◽

Nanocrystalline Anatase Tio2

Pure and Fe(III)-doped TiO2 suspensions were prepared by the sol gel method with the use of titanium isopropoxide (Ti(OPri)4) as precursor material. The properties of doped materials were compared to TiO2 properties based on the characterization by thermal analysis (TG-DTA and DSC), X-ray powder diffractometry and spectroscopy measurements (FTIR). Both undoped and doped TiO2 suspensions were used to coat metallic substrate as a mean to make thin-film electrodes. Thermal treatment of the precursors at 400°C for 2 h in air resulted in the formation of nanocrystalline anatase TiO2. The thin-film electrodes were tested with respect to their photocatalytic performance for degradation of a textile dye in aqueous solution. The plain TiO2 remains as the best catalyst at the conditions used in this report.

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