Experimental Investigation of TiO2-water Nanofluids Thermal Conductivity Synthesized by Sol-gel Technique

Silica aerogels are the most widely studied type of aerogel. However, its application still suffers from low mechanical strength and high production cost. The paper studies the use of recyclable PVC as the backbone material of the aerogel and introduces an economically friendly fabrication process of flexible PVC aerogel using sol-gel technique and ambient drying instead of the CO2 critical drying. Three different types of PVC powder with the molecule weight of 43000, 48000, and 80000 respectively are chosen and dissolved in DMF in five different concentrations-0.2, 0.4, 0.6, 0.8, and 1.0 g (mL)-1. The lowest thermal conductivity of the aerogel is measured using hot-wire method as 0.0323W(m*K)-1, which is made of PVC with molecule weight of 80000 in a concentration of 0.4g (mL)-1. The analysis based on SEM pictures shows that PVC type and concentration would greatly influence aerogel’s structure thus affecting its thermal conductivity. The optimal solution for producing low thermal conductivity aerogel is to use PVC powder with low molecule weight with a concentration between 0.2 and 0.6 g (mL)-1.

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Study of the Structure, Microstructure and Temperature Dependent Thermal Conductivity Properties of SrTiO3: Via Y3+ Substitution

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.69.33 ◽

2021 ◽

Vol 69 ◽

pp. 33-42

Author(s):

Mohammed Tihtih ◽

Jamal Eldin F.M. Ibrahim ◽

Emese Kurovics ◽

László A. Gömze

Keyword(s):

Thermal Conductivity ◽

Lattice Strain ◽

Sol Gel ◽

X Ray Diffraction ◽

Temperature Dependent ◽

Xrd Pattern ◽

X Ray ◽

Gel Technique ◽

Temperature Dependent Thermal Conductivity

Yttrium (Y) modified strontium titanate (SrTiO3) powders with initial concentration of Y in the range of 0 to 15 mol% were produced through sol-gel technique. X-ray diffraction (XRD) studies show that all the prepared compounds have a perovskite cubic structure with the space group (Pm3m). The lattice constant, lattice strain and crystallite size of the as-prepared samples were estimated from the XRD pattern which reveals the incorporation of Y into SrTiO3 system, moreover to investigate the quality of the prepared SrYT ceramics powder, the scanning electron microscopy (SEM) was used to determined investigate the morphology, grain size and its distribution. The analysis of the thermal conductivity measurements performed on the obtained powders revealed the effect of the combination of temperature and Y content on the thermal conductivity value, Indeed, the minimum thermal conductivity was 4.12 W/(mK) obtained with 15%Y at 464 K.

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Preparation of AlN microspheres/UHMWPE composites for insulating thermal conductors

RSC Advances ◽

10.1039/c6ra18228c ◽

2016 ◽

Vol 6 (83) ◽

pp. 80262-80267 ◽

Cited By ~ 18

Author(s):

Yuan Wang ◽

Xvsheng Qiao ◽

Jun Wan ◽

Yao Xiao ◽

Xianping Fan

Keyword(s):

Thermal Conductivity ◽

Sol Gel ◽

Gel Technique ◽

Uhmwpe Composites ◽

Uhmwpe Composite

AlN microspheres were prepared by applying both sol–gel technique and gas reduction nitridation. The AlN microspheres/UHMWPE composite demonstrated much higher thermal conductivity in comparison with the commercial AlN particles/UHMWPE composite.

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Preparation and Deposition of Hydroxyapatite on Biomaterials by Sol-Gel Technique-A Review

Chitkara Chemistry Review ◽

10.15415/ccr.2013.12011 ◽

2013 ◽

Vol 1 (2) ◽

pp. 59-69 ◽

Cited By ~ 6

Author(s):

Sarbjit Kaur ◽

Niraj Bala ◽

Charu Khosla

Keyword(s):

Sol Gel ◽

Gel Technique

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Sol - Gel Technique Applied for Biomaterials Achievement

Recent Patents on Materials Science ◽

10.2174/1874464811104030224 ◽

2011 ◽

Vol 4 (3) ◽

pp. 224-237 ◽

Cited By ~ 3

Author(s):

Aurica P. Chiriac ◽

Loredana E. Nita ◽

Iordana Neamtu ◽

Manuela T. Nistor

Keyword(s):

Sol Gel ◽

Gel Technique

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Structural and thermal properties of monolithic silica–phosphate (SiO2–P2O5) gel glasses prepared by sol–gel technique

Journal of Sol-Gel Science and Technology ◽

10.1007/s10971-011-2420-0 ◽

2011 ◽

Vol 58 (2) ◽

pp. 507-517 ◽

Cited By ~ 14

Author(s):

M. Kamal ◽

I. K. Battisha ◽

M. A. Salem ◽

A. M. S. El Nahrawy

Keyword(s):

Thermal Properties ◽

Sol Gel ◽

Monolithic Silica ◽

Gel Technique ◽

Gel Glasses

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Effect of alkali metal (Na, K) ion ratio on structural, optical and photoluminescence properties of K0.5Na0.5NbO3 ceramics prepared by sol–gel technique

Bulletin of Materials Science ◽

10.1007/s12034-020-02341-x ◽

2021 ◽

Vol 44 (1) ◽

Author(s):

SHAMMI KUMAR ◽

NAGESH THAKUR

Keyword(s):

Alkali Metal ◽

Sol Gel ◽

Photoluminescence Properties ◽

Gel Technique

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Tailoring Mesoporous Titania Features by Ultrasound-Assisted Sol-Gel Technique: Effect of Surfactant/Titania Precursor Weight Ratio

Nanomaterials ◽

10.3390/nano11051263 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1263

Author(s):

Elvira Mahu ◽

Cristina Giorgiana Coromelci ◽

Doina Lutic ◽

Iuliean Vasile Asaftei ◽

Liviu Sacarescu ◽

...

Keyword(s):

Photocatalytic Activity ◽

Sol Gel ◽

Weight Ratio ◽

Soft Template ◽

Synthesis Process ◽

Mesoporous Titania ◽

Cavitation Effect ◽

Titania Precursor ◽

Gel Technique ◽

Ultrasound Assisted

A mesoporous titania structure has been prepared using the ultrasound-assisted sol-gel technique in order to find out a way to tailor its structure. The TiO2 obtained was compared to the same version of titania but synthesized by a conventional sol-gel method with the objective of understanding the effect of ultrasound in the synthesis process. All synthesis experiments were focused on the preparation of a titania photocatalyst. Thus, the anatase photocatalytic active phase of titania was proven by X-ray diffraction. Additionally, the ultrasonation treatment proved to increase the crystallinity of titania samples, being one of the requirements to having good photocatalytic activity for titania. The influence of surfactant/titania precursor weight ratio on the structural (XRD), textural (N2-sorption measurements), morphological (TEM), surface chemistry (FTIR) and optical properties (UVDR) was investigated. It was observed that the crystallite size, specific surface area, band gap energy and even photocatalytic activity was affected by the synergism occurring between cavitation effect and the surfactant/titania precursor weight ratio. The study yielded interesting great results that could be considered for further application of ultrasound to tailor mesoporous titania features via sol-gel soft template synthesis, against conventional sol-gel process.

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