**Recent Advances in Thermoelectric Materials for High Efficiency Energy Conversion and Refrigeration**

Editor

**Paolo Mele**

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*Editor* Paolo Mele Shibaura Institute of Technology Japan

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This is a reprint of articles from the Special Issue published online in the open access journal *Materials* (ISSN 1996-1944) (available at: https://www.mdpi.com/journal/materials/special issues/ thermoelectr mater).

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## **Contents**


## **About the Editor**

**Paolo Mele** is currently Professor at SIT Research Laboratories, Shibaura Institute of Technology, Tokyo, Japan. He obtained a Master's degree in Chemistry and a Ph.D. in Chemical Sciences at Genova University (Italy). In 2003, he moved to ISTEC-SRL in Tokyo to study melt-textured ceramic superconductors. Then, he worked as a postdoctoral researcher at Kyoto University (JSPS fellowship) from 2004 to 2007, at the Kyushu Institute of Technology (JST fellowship) from 2007 to 2011, at Hiroshima University (as a lecturer) from 2011 to 2014, and at Muroran Institute of Technology (as an associate professor) from 2015 to 2018 before taking up his current position. His research interests include materials for energy and sustainable development (superconductors and thermoelectrics); the fabrication and characterization of thin films of oxides, ceramics, and metals; the study of the effect of nanostructuration on the physical properties; thermal transport; and vortex matter. He is the author of more than 110 papers in international scientific journals and four book chapters, has two patents, and has contributed to hundreds of communications at international conferences. He has co-edited nine books on superconductors, oxides, thin films, thermoelectrics, and other materials for energy.

### *Editorial* **Special Issue "Recent Advances in Thermoelectric Materials for High Efficiency Energy Conversion and Refrigeration"**

**Paolo Mele 1,2**


It has been almost three years since I enthusiastically accepted to be guest editor for this Special Issue of *Materials*, entitled "Recent Advances in Thermoelectric Materials for High Efficiency Energy Conversion and Refrigeration".

Thermoelectricity is a well-known phenomenon enabling the conversion of heat into electric energy without moving parts. Its exploitation has been widely considered to contribute to the increasing need for energy along with the concerns about the environmental impact of traditional fossil energy sources. In the last few years, significant improvements in the performance of thermoelectric materials have been achieved through chemical doping, solid solution formation, and nanoengineering approaches. Furthermore, the feasibility of flexible, stretchable, and conformable thermoelectric harvesters has been demonstrated and has attracted the interest of a wide audience. However, the path for practical applications of thermoelectrics still appears long.

This Special Issue of *Materials* was intended as an effort to bridge the gap between materials science and applications of thermoelectric materials.

Originally, many topics were welcome: new thermoelectric compounds; correlation between material structure and thermoelectric properties; bulk thermoelectric ceramics, oxides, and chalcogenides; bulk thermoelectric alloys and intermetallics; organic and polymeric thermoelectrics; thermoelectric thin films, multilayers, and nanocomposites; theory and modeling; thermal transport and thermal conductivity; applications and devices based on thermoelectric materials; standardization and metrology; and more.

The five published papers reflect the original spirit of the Special Issue, going from skutterudite materials to sulfides and oxides and covering various aspects of materials preparation and characterization.

With the great hope that it will contribute to pave the way for wide diffusion of thermoelectric materials in society and daily life, I declare this Special Issue closed thanking all the colleagues and all the editorial staff of *Materials* for their great contributions and everlasting support.

**Funding:** This research received no external funding.

**Conflicts of Interest:** The author declares no conflict of interest.

**Citation:** Mele, P. Special Issue "Recent Advances in Thermoelectric Materials for High Efficiency Energy Conversion and Refrigeration". *Materials* **2022**, *15*, 1672. https:// doi.org/10.3390/ma15051672

Received: 5 February 2022 Accepted: 16 February 2022 Published: 23 February 2022

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**Copyright:** © 2022 by the author. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

*Article*
