Enhanced Thermoelectric Performance by Surface Engineering in SnTe-PbS Nanocomposites

Thermoelectric materials enable the direct conversion between heat and electricity. SnTe is a promising candidate due to its high charge transport performance. Here, we prepared SnTe nanocomposites by employing an aqueous method to synthetize SnTe nanoparticles (NP), followed by a unique surface treatment prior NP consolidation. This synthetic approach allowed optimizing the charge and phonon transport synergistically. The novelty of this strategy was the use of a soluble PbS molecular complex prepared using a thiol-amine solvent mixture that upon blending is adsorbed on the SnTe NP surface. Upon consolidation with spark plasma sintering, SnTe-PbS nanocomposite is formed. The presence of PbS complexes significantly compensates for the Sn vacancy and increases the average grain size of the nanocomposite, thus improving the carrier mobility. Moreover, lattice thermal conductivity is also reduced by the Pb and S-induced mass and strain fluctuation. As a result, an enhanced ZT of ca. 0.8 is reached at 873 K. Our finding provides a novel strategy to conduct rational surface treatment on NP-based thermoelectrics.

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Rational Surface Engineering of MXene@N-doping Hollow Carbon Dual-confined Cobalt Sulfides/Selenides for Advanced Aluminum Batteries

Journal of Materials Chemistry A ◽

10.1039/d1ta03465k ◽

2021 ◽

Author(s):

Long Yao ◽

Shunlong Ju ◽

Xuebin Yu

Keyword(s):

Surface Engineering ◽

Rational Surface ◽

Natural Abundance ◽

Multivalent Ions ◽

N Doping ◽

Hollow Carbon

Rechargeable aluminum batteries (RABs) based on multivalent ions transfer have attracted great attention due to their large specific capacities, natural abundance, and high safety of metallic Al anode. However, the...

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Composite Layers “MgAl Intermetalic Layer / PVD Coating” Obtained On The AZ91D Magnesium Alloy By Different Hybrid Surface Treatment Methods

Archives of Metallurgy and Materials ◽

10.1515/amm-2015-0255 ◽

2015 ◽

Vol 60 (2) ◽

pp. 1031-1035 ◽

Cited By ~ 4

Author(s):

J. Smolik ◽

A. Mazurkiewicz ◽

J. Kacprzyńska-Gołacka ◽

M. Rydzewski ◽

M. Szota ◽

...

Keyword(s):

Surface Treatment ◽

Magnesium Alloys ◽

Surface Engineering ◽

Composite Layer ◽

Electron Beam Evaporation ◽

Treatment Technology ◽

Corrosion Properties ◽

Pvd Coating ◽

Composite Layers ◽

Coating Composite

Abstract Magnesium alloys have very interesting physical properties which make them ‘materials of the future’ for tools and machine components in many industry areas. However, very low corrosion and tribological resistance of magnesium alloys hampers the implementation of this material in the industry. One of the methods to improve the properties of magnesium alloys is the application of the solutions of surface engineering like hybrid technologies. In this paper, the authors compare the tribological and corrosion properties of two types of “MgAlitermetalic / PVD coating” composite layers obtained by two different hybrid surface treatment technologies. In the first configuration, the “MgAlitermetalic / PVD coating” composite layer was obtained by multisource hybrid surface treatment technology combining magnetron sputtering (MS), arc evaporation (AE) and vacuum heating methods. The second type of a composite layer was prepared using a hybrid technology combined with a diffusion treatment process in Al-powder and the electron beam evaporation (EB) method. The authors conclude, that even though the application of „MgAlitermetalic / PVD coating” composite layers can be an effective solution to increase the abrasive wear resistance of magnesium alloys, it is not a good solution to increase its corrosion resistance.

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Preparation and Magnetic Properties of Dense NiCuZn Ferrite by Spark Plasma Sintering

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.368-372.601 ◽

2008 ◽

Vol 368-372 ◽

pp. 601-603

Author(s):

Xi Wei Qi ◽

Ji Zhou ◽

Zhen Xing Yue ◽

Ming Ya Li ◽

Xiu Mei Han

Keyword(s):

Spark Plasma Sintering ◽

Annealing Temperature ◽

Annealing Treatment ◽

Impurity Phase ◽

Uniaxial Pressure ◽

Plasma Sintering ◽

Average Grain Size ◽

Conventional Sintering ◽

Spark Plasma ◽

Nicuzn Ferrite

Dense NiCuZn ferrites consisting of fine grains were prepared by spark plasma sintering (SPS) at 750°C for 3 min under a uniaxial pressure of 15 MPa. The powders were densified to >95% of theoretical density by the SPS process, and the average grain size of the prepared NiCuZn ferrite was < 1 /m. The saturation magnetization of prepared specimens (without further annealing treatment) was approximate 50.54 emu/g, which was slightly smaller than that of 52.21 emu/g for specimens prepared by conventional sintering at 980°C for 4 h. Phase identifications indicated that prepared NiCuZn ferrite existed impurity phase (Cu2O), and Cu2O would gradually transform to CuO when annealing temperature increased.

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Formation and Properties of the Ta-Y2O3, Ta-ZrO2, and Ta-TaC Nanocomposites

Advances in Materials Science and Engineering ◽

10.1155/2018/2085368 ◽

2018 ◽

Vol 2018 ◽

pp. 1-12

Author(s):

J. Jakubowicz ◽

M. Sopata ◽

G. Adamek ◽

P. Siwak ◽

T. Kachlicki

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Mechanical Alloying ◽

Young’S Modulus ◽

Young's Modulus ◽

Ceramic Composites ◽

Ceramic Phase ◽

Plasma Sintering ◽

Average Grain Size ◽

Bulk Nanocrystalline

The nanocrystalline tantalum-ceramic composites were made using mechanical alloying followed by pulse plasma sintering (PPS). The tantalum acts as a matrix, to which the ceramic reinforced phase in the concentration of 5, 10, 20, and 40 wt.% was introduced. Oxides (Y2O3 and ZrO2) and carbides (TaC) were used as the ceramic phase. The mechanical alloying results in the formation of nanocrystalline grains. The subsequent hot pressing in the mode of PPS results in the consolidation of powders and formation of bulk nanocomposites. All the bulk composites have the average grain size from 40 nm to 100 nm, whereas, for comparison, the bulk nanocrystalline pure tantalum has the average grain size of approximately 170 nm. The ceramic phase refines the grain size in the Ta nanocomposites. The mechanical properties were studied using the nanoindentation tests. The nanocomposites exhibit uniform load-displacement curves indicating good integrity and homogeneity of the samples. Out of the investigated components, the Ta-10 wt.% TaC one has the highest hardness and a very high Young’s modulus (1398 HV and 336 GPa, resp.). For the Ta-oxide composites, Ta-20 wt.% Y2O3 has the highest mechanical properties (1165 HV hardness and 231 GPa Young’s modulus).

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Customizable Ceramic Nanocomposites Using Carbon Nanotubes

Molecules ◽

10.3390/molecules24173176 ◽

2019 ◽

Vol 24 (17) ◽

pp. 3176

Author(s):

Chinyere Okolo ◽

Rafaila Rafique ◽

Sadia Sagar Iqbal ◽

Tayyab Subhani ◽

Mohd Shahneel Saharudin ◽

...

Keyword(s):

Carbon Nanotube ◽

Substantial Reduction ◽

Industrial Applications ◽

Plasma Sintering ◽

Electrical Conductivities ◽

Spark Plasma ◽

Novel Strategy ◽

Further Development ◽

Ceramic Matrices ◽

Ceramic Nanocomposites

A novel tweakable nanocomposite was prepared by spark plasma sintering followed by systematic oxidation of carbon nanotube (CNT) molecules to produce alumina/carbon nanotube nanocomposites with surface porosities. The mechanical properties (flexural strength and fracture toughness), surface area, and electrical conductivities were characterized and compared. The nanocomposites were extensively analyzed by field emission scanning electron microscopy (FE-SEM) for 2D qualitative surface morphological analysis. Adding CNTs in ceramic matrices and then systematically oxidizing them, without substantial reduction in densification, induces significant capability to achieve desirable/application oriented balance between mechanical, electrical, and catalytic properties of these ceramic nanocomposites. This novel strategy, upon further development, opens new level of opportunities for real-world/industrial applications of these relatively novel engineering materials.

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Spark plasma sintering for multi-scale surface engineering of materials

JOM ◽

10.1007/s11837-010-0090-y ◽

2010 ◽

Vol 62 (6) ◽

pp. 65-71 ◽

Cited By ~ 11

Author(s):

Mrinalini Mulukutla ◽

Ashish Singh ◽

Sandip P. Harimkar

Keyword(s):

Spark Plasma Sintering ◽

Surface Engineering ◽

Multi Scale ◽

Plasma Sintering ◽

Spark Plasma ◽

Scale Surface

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Dye Sensitized Solar Cells with Enhanced Performance Using TiO2 Nanotubes via Rational Surface Engineering

ECS Meeting Abstracts ◽

10.1149/ma2011-01/38/1817 ◽

2011 ◽

Keyword(s):

Solar Cells ◽

Tio2 Nanotubes ◽

Surface Engineering ◽

Dye Sensitized Solar Cells ◽

Rational Surface ◽

Dye Sensitized ◽

Sensitized Solar Cells

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Hierarchical Hollow-Microsphere Metal-Selenide@Carbon Composites with Rational Surface Engineering for Advanced Sodium Storage

Advanced Energy Materials ◽

10.1002/aenm.201803035 ◽

2018 ◽

Vol 9 (1) ◽

pp. 1803035 ◽

Cited By ~ 89

Author(s):

Peng Ge ◽

Sijie Li ◽

Laiqiang Xu ◽

Kangyu Zou ◽

Xu Gao ◽

...

Keyword(s):

Surface Engineering ◽

Hollow Microsphere ◽

Rational Surface ◽

Carbon Composites ◽

Sodium Storage

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Preparation of Fine-grained BaTiO3 Ceramics by Spark Plasma Sintering

Journal of Materials Research ◽

10.1557/jmr.2002.0081 ◽

2002 ◽

Vol 17 (3) ◽

pp. 575-581 ◽

Cited By ~ 51

Author(s):

Tomonari Takeuchi ◽

Claudio Capiglia ◽

Nalini Balakrishnan ◽

Yasuo Takeda ◽

Hiroyuki Kageyama

Keyword(s):

Grain Size ◽

Spark Plasma Sintering ◽

Fine Powder ◽

Fine Grained ◽

Plasma Sintering ◽

Average Grain Size ◽

Ferroelectric Domains ◽

Spark Plasma ◽

Ray Density ◽

Permittivity Measurements

Dense BaTiO3 ceramics consisting of fine grains were prepared using fine powder (average grain size of 0.06 μm; BT006) as a starting material and the spark plasma sintering (SPS) method. The powder was densified to >95% of theoretical x-ray density by the SPS process, and the average grain size of the resulting ceramics was <0.5 μm; the particle size of the initial powder significantly affects the grain size of the resulting SPS pellets. Fixed-frequency (100 kHz), room-temperature permittivity measurements of the BT006-SPS ceramics showed relatively low values (3000–3500) compared with those (typically 5000) for SPS ceramics consisting of larger grains (approximately 1 μm). Lower permittivity was attributed to poor development of ferroelectric domains in the ceramics, which originated from incomplete development of the tetragonal structure as well as the presence of a local orthorhombic structure.

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