Defect engineering in thermoelectric materials: what have we learned?

Conducting polymers are extensively studied due to their outstanding properties, including tunable electrical property, optical and high mechanical properties, easy synthesis and effortless fabrication and high environmental stability over conventional inorganic materials.

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Nanostructure controlled construction of high-performance thermoelectric materials of polymers and their composites

Journal of Materials Chemistry A ◽

10.1039/c8ta09656b ◽

2018 ◽

Vol 6 (45) ◽

pp. 22381-22390 ◽

Cited By ~ 24

Author(s):

Yufeng Xue ◽

Chunmei Gao ◽

Lirong Liang ◽

Xin Wang ◽

Guangming Chen

Keyword(s):

Thermoelectric Materials ◽

High Performance ◽

Thermoelectric Performance ◽

Recent Advances

This review discusses recent advances in controlled fabrication of nanostructures and the enhanced thermoelectric performance of polymers and their composites.

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Recent Advances in Multi-Functional Coatings for Soft Magnetic Composites

Materials ◽

10.3390/ma14226844 ◽

2021 ◽

Vol 14 (22) ◽

pp. 6844

Author(s):

Emir Pošković ◽

Fausto Franchini ◽

Luca Ferraris ◽

Elisa Fracchia ◽

Jana Bidulska ◽

...

Keyword(s):

Mechanical Properties ◽

State Of The Art ◽

Inorganic Materials ◽

Organic Layer ◽

Soft Magnetic ◽

Research Activity ◽

Magnetic Composites ◽

Recent Advances ◽

Starting Point ◽

Soft Magnetic Composites

During the past 50 years, the aim to reduce the eddy current losses in magnetic cores to a minimum led to the formulation of new materials starting from electrically insulated iron powders, today called Soft Magnetic Composites (SMC). Nowadays, this promising branch of materials is still held back by the mandatory tradeoff between energetic, electrical, magnetic, and mechanical performances. In most cases, the research activity focuses on the deposition of an insulating/binding layer, being one of the critical points in optimizing the final composite. This insulation usually is achieved by either inorganic or organic layer constituents. The main difference is the temperature limit since most inorganic materials typically withstand higher treatment temperatures. As a result, the literature shows many materials and process approaches, each one designed to meet a specific application. The present work summarizes the recent advances in state of the art, analyzing the relationship among material compositions and magnetic and mechanical properties. Each coating shows its own processing sets, which vary from simple mechanical mixing to advanced chemical methods to metallurgical treatments. From state of the art, Aluminum coatings are characterized by higher current losses and low mechanical properties. In contrast, higher mechanical properties are obtained by adopting Silicon coatings. The phosphates coatings show the best-balanced overall properties. Each coating type was thoroughly investigated and then compared with the literature background highlighting. The present paper thus represents a critical overview of the topic that could serve as a starting point for the design and development of new and high-performing coating solutions for SMCs. However, global research activity continuously refines the recipes, introducing new layer materials. The following steps and advances will determine whetherthese materials breakthrough in the market.

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Hybrid Thermoelectrics

Annual Review of Materials Research ◽

10.1146/annurev-matsci-082319-111001 ◽

2020 ◽

Vol 50 (1) ◽

pp. 319-344

Author(s):

Jia Liang ◽

Shujia Yin ◽

Chunlei Wan

Keyword(s):

Solid State ◽

Hybrid Materials ◽

Thermoelectric Materials ◽

Hybrid Composites ◽

Inorganic Materials ◽

Atomic Scale ◽

Thermoelectric Performance ◽

New Techniques ◽

Compositional Diversity ◽

Solid State Cooling

Constructing hybrid composites with organic and inorganic materials at different length scales provides unconventional opportunities in the field of thermoelectric materials, which are classified as hybrid crystal, superlattice, and nanocomposite. A variety of new techniques have been proposed to fabricate hybrid thermoelectric materials with homogeneous microstructures and intimate interfaces, which are critical for good thermoelectric performance. The combination of organic and inorganic materials at the nano or atomic scale can cause strong perturbation in the structural, electron, and phonon characteristics, providing new mechanisms to decouple electrical and thermal transport properties that are not attainable in the pure organic or inorganic counterparts. Because of their increasing thermoelectric performance, compositional diversity, mechanical flexibility, and ease of fabrication, hybrid materials have become the most promising candidates for flexible energy harvesting and solid-state cooling.

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Thermoelectric Materials for Textile Applications

Molecules ◽

10.3390/molecules26113154 ◽

2021 ◽

Vol 26 (11) ◽

pp. 3154

Author(s):

Kony Chatterjee ◽

Tushar K. Ghosh

Keyword(s):

Thermal Conductivity ◽

Carbon Nanotubes ◽

Seebeck Coefficient ◽

Thermoelectric Materials ◽

Figure Of Merit ◽

Inorganic Materials ◽

Peltier Effect ◽

Electronic Textiles ◽

Heating And Cooling ◽

Recent Attention

Since prehistoric times, textiles have served an important role–providing necessary protection and comfort. Recently, the rise of electronic textiles (e-textiles) as part of the larger efforts to develop smart textiles, has paved the way for enhancing textile functionalities including sensing, energy harvesting, and active heating and cooling. Recent attention has focused on the integration of thermoelectric (TE) functionalities into textiles—making fabrics capable of either converting body heating into electricity (Seebeck effect) or conversely using electricity to provide next-to-skin heating/cooling (Peltier effect). Various TE materials have been explored, classified broadly into (i) inorganic, (ii) organic, and (iii) hybrid organic-inorganic. TE figure-of-merit (ZT) is commonly used to correlate Seebeck coefficient, electrical and thermal conductivity. For textiles, it is important to think of appropriate materials not just in terms of ZT, but also whether they are flexible, conformable, and easily processable. Commercial TEs usually compromise rigid, sometimes toxic, inorganic materials such as bismuth and lead. For textiles, organic and hybrid TE materials are more appropriate. Carbon-based TE materials have been especially attractive since graphene and carbon nanotubes have excellent transport properties with easy modifications to create TE materials with high ZT and textile compatibility. This review focuses on flexible TE materials and their integration into textiles.

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Recent advances in the design of inorganic and nano-clay particles for the treatment of brain disorders

Journal of Materials Chemistry B ◽

10.1039/d0tb02957b ◽

2021 ◽

Author(s):

Francesca Persano ◽

Svetlana Batasheva ◽

Gölnur Fakhrullina ◽

Giuseppe Gigli ◽

Stefano Leporatti ◽

...

Keyword(s):

Drug Delivery ◽

Silica Nanoparticles ◽

Biomedical Applications ◽

Inorganic Materials ◽

Brain Disorders ◽

Clay Particles ◽

Recent Advances ◽

Wide Range ◽

Nano Clay

Inorganic materials, in particular nanoclays and silica nanoparticles, have attracted enormous attention due to their versatile and tuneable properties, making them ideal candidates for a wide range of biomedical applications, such as drug delivery.

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Fabrication of Bi-Te Based Thermoelectric Semiconductors by Using Hybrid Powders

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.297-300.875 ◽

2005 ◽

Vol 297-300 ◽

pp. 875-880

Author(s):

Cheol Ho Lim ◽

Ki Tae Kim ◽

Yong Hwan Kim ◽

Dong Choul Cho ◽

Young Sup Lee ◽

...

Keyword(s):

Mechanical Properties ◽

Single Crystals ◽

Thermoelectric Properties ◽

Thermoelectric Materials ◽

Figure Of Merit ◽

Bending Strength ◽

Mixing Ratio ◽

Plasma Sintering ◽

Spark Plasma ◽

P Type

P-type Bi0.5Sb1.5Te3 compounds doped with 3wt% Te were fabricated by spark plasma sintering and their mechanical and thermoelectric properties were investigated. The sintered compounds with the bending strength of more than 50MPa and the figure-of-merit 2.9×10-3/K were obtained by controlling the mixing ratio of large powders (PL) and small powders (PS). Compared with the conventionally prepared single crystal thermoelectric materials, the bending strength was increased up to more than three times and the figure-of-merit Z was similar those of single crystals. It is expected that the mechanical properties could be improved by using hybrid powders without degradation of thermoelectric properties.

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Monitoring morphology and properties of hybrid organicinorganic materials from in situ polymerization of tetraethoxysilane in polyimide polymer: 1. Effect of the coupling agent on the microstructure and interfacial interaction

e-Polymers ◽

10.1515/epoly.2006.6.1.117 ◽

2006 ◽

Vol 6 (1) ◽

Cited By ~ 1

Author(s):

Hamid Kaddami ◽

Carsten Becker-Willinger ◽

Helmut Schmid

Keyword(s):

Mechanical Properties ◽

Hybrid Materials ◽

Coupling Agent ◽

In Situ Polymerization ◽

Interfacial Interaction ◽

Inorganic Materials ◽

Hybrid Films ◽

Morphological Transformation ◽

Temperature Relaxation ◽

Saxs Analysis

AbstractTransmission electron microscopy (TEM), small angle X-ray (SAXS) and dynamical mechanical thermal analysis (DMTA) were used to characterize the morphology and thermo-mechanical properties of hybrid organic inorganic materials. These materials were based on polyimide (PI) and tetraethoxysilane (TEOS). Polyimide polymer is prepared from 4,4’-oxydianiline (ODA) 2,2-Bis(3- amino-4-hydroxyphenyl) hexafluoro-propane (6F-OHDA) pyromellitic dianhydride (PMDA) polyamic polymer. In one family of hybrid materials 3- isocyanatopropyltriethoxysilane (ICTS) is used as coupling agent in order to enhance the interfacial interaction between polyimide and silica. It was possible to modulate the morphology as well as the optical and thermo-mechanical properties of these hybrid materials depending on the formulation used. TEM and SAXS analysis indicated that silica domains on the nanoscale level are obtained when coupling agent is used in the formulation. Additionally the TEM and SAXS analysis indicated that miscibility of the organic and the inorganic phases on the molecular scale is obtained in the hybrid films when ICTS as coupling agent is added to the polyamic acid. These techniques show a fractal structure of the hybrid materials with coupling agent. This was confirmed with DMTA analysis which shows very high temperature relaxation (more than 450°C). From this result it could be derived that the addition of ICTS causes a morphological transformation from discrete particulate microstructure to fine interpenetrated or co-continuous phases. The intimate miscibility of the phases is accompanied at the same time by the amelioration of thermo-mechanical properties of the hybrid films.

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