Preparation by Poly(Acrylic Acid) Sol–Gel Method and Thermoelectric Properties of γ-Na
                x
            CoO2 Bulk Materials

Improving silica film’s contact angle (CA) using tetraethoxysilane (TEOS) and iso-butyltrimethoxysilane (iso-BTMS) by the sol-gel method without adding organo-fluoride substances is of interest. Five factors, namely type of solvent, molar ratio and amounts of TEOS and iso-BTMS, mixing intensity, sol aging time, and presence and absence of poly-acrylic acid (PAA), were assessed to improve the static water CA of the film and its surface quality. Results revealed that when ethanol was used as the dissolving solvent and after adding initial iso-BTMS and TEOS concentrations of 0.0270 and 0.0194 mol/L (molar ratio = 1.39), respectively, without sonication and adding PAA/TEOS weight ratio of 0.029, then the maximum static CA of the film reached 147°, a nearly super-hydrophobic surface. Under given conditions, long-term film durability was observed, and the added PAA prevented the formation of nonhomogeneous film surfaces caused by the highly clustering aggregation of silanols under high pH conditions.

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The sol-gel method synthetics and the thermoelectric properties analyze of Ca3Co4O9

10.1063/1.4971894 ◽

2017 ◽

Author(s):

Jiaolian Luo ◽

Weifu Cen ◽

Wenjing Zhang ◽

Ping Zou ◽

Peng Tang ◽

...

Keyword(s):

Thermoelectric Properties ◽

Sol Gel ◽

Gel Method ◽

Sol Gel Method

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Enhanced Thermoelectric Properties of Ca3−xAgxCo4O9 by the Sol–Gel Method with Spontaneous Combustion and Cold Isostatic Pressing

Materials ◽

10.3390/ma11122573 ◽

2018 ◽

Vol 11 (12) ◽

pp. 2573

Author(s):

Youyu Fan ◽

Xiaoling Qi ◽

Dechang Zeng

Keyword(s):

Thermoelectric Properties ◽

Figure Of Merit ◽

Spontaneous Combustion ◽

Sol Gel ◽

Cold Isostatic Pressing ◽

X Ray Diffraction ◽

Gel Method ◽

Sol Gel Method ◽

Isostatic Pressing ◽

Opposite Case

In this study, Ca3−xAgxCo4O9 ceramics were synthesized by the sol–gel method combined with spontaneous combustion and cold isostatic pressing. The Ca3−xAgxCo4O9 ceramics were characterized via X-ray diffraction and scanning electron microscopy. Thermoelectric properties of the ceramics were measured from 323 to 673 K. The results indicated that Ag doping significantly affected the microstructure and thermoelectric properties. With the increase in Ag content and gradual increase in electrical conductivity, the Seebeck coefficient first increased and then decreased, whereas the thermal conductivity exhibited the opposite case. The figure of merit, ZT, was 0.17 at 673 K for the Ca2.8Ag0.2Co4O9 sample. These results indicated that the thermoelectric properties could be optimized remarkably with the substitution of Ag.

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Preparation of p-type CuCr1−x Mg x O2 bulk with improved thermoelectric properties by sol–gel method

Journal of Sol-Gel Science and Technology ◽

10.1007/s10971-012-2732-8 ◽

2012 ◽

Vol 63 (1) ◽

pp. 1-7 ◽

Cited By ~ 11

Author(s):

Qinggang Meng ◽

Shanfu Lu ◽

Sunhui Lu ◽

Yan Xiang

Keyword(s):

Thermoelectric Properties ◽

Sol Gel ◽

Gel Method ◽

Sol Gel Method ◽

P Type

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Effect of Co-Doping on Thermoelectric Properties of n-Type Bi2Te3 Nanostructures Fabricated Using a Low-Temperature Sol-Gel Method

Nanomaterials ◽

10.3390/nano11102719 ◽

2021 ◽

Vol 11 (10) ◽

pp. 2719

Author(s):

Syed Irfan ◽

Muhammad Aizaz Ud Din ◽

Muhammad Qaisar Manzoor ◽

Deliang Chen

Keyword(s):

Low Temperature ◽

Seebeck Coefficient ◽

Spark Plasma Sintering ◽

Thermoelectric Properties ◽

Sol Gel ◽

Gel Method ◽

Sol Gel Method ◽

Plasma Sintering ◽

Spark Plasma ◽

Co Doped

In this work, a novel low-temperature double solvent sol-gel method was used to fabricate (Sm, Ce, Gd) and (Sn, Se, I) co-doped at Bi and Te-sites, respectively, for Bi2Te3 nanostructures. The phase-purity and high crystallinity of as-synthesized nanostructures were confirmed using X-ray diffraction and high-resolution transmission electron microscopy. The nanopowders were hot-pressed by spark plasma sintering into bulk pellets for thermoelectric properties. The spark plasma sintering temperature significantly affects the Seebeck coefficient and electrical conductivity of bulk Bi2Te3 pellets. The electrical conductivities of co-doped samples decrease with an increase in the temperature, but conversely, the Seebeck coefficient is linearly increasing. The power factor showed that the co-dopants enhanced the thermoelectric properties of Bi2Te3 nanopowders.

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