Citation
Palacios Clemente, Pablo and Wahnón Benarroch, Perla and Ortega Perez, Silvia Natividad and Lu, Jinyu and Fuster De La Mata, Juan Maria and Liu, Yu and Garcia, Gregorio and Ortega, Silvia and Cadavid, Doris and Ibanez, Maria and Xi, Lili and De Roo, Jonathan and Lopez, Antonio M. and Marti-sanchez, Sara and Cabezas, Ignasi and De La Mata, Maria and Luo, Zhishan and Dun, Chaochao and Dobrozhan, Oleksandr and Carroll, David L. and Zhang, Wenqing and Martins, Jose and Kovalenko, Maksym V. and Arbiol, Jordi and Noriega, German and Song, Jiming and Cabot, Andreu
(2017).
Solution-based synthesis and processing of Sn- and Bi-doped Cu3SbSe4 nanocrystals, nanomaterials and ring-shaped thermoelectric generators.
"Journal of Materials Chemistry A", v. 5
(n. 6);
pp. 2592-2602.
ISSN 2050-7488.
https://doi.org/10.1039/c6ta08467b.
Abstract
Copper-based chalcogenides that comprise abundant, low-cost, and environmental friendly elements are
excellent materials for a number of energy conversion applications, including photovoltaics, photocatalysis,
and thermoelectrics (TE). In such applications, the use of solution-processed nanocrystals (NCs) to produce
thin films or bulk nanomaterials has associated several potential advantages, such as high material yield and
throughput, and composition control with unmatched spatial resolution and cost. Here we report on the
production of Cu3SbSe4 (CASe) NCs with tuned amounts of Sn and Bi dopants. After proper ligand removal,
as monitored by nuclear magnetic resonance and infrared spectroscopy, these NCs were used to produce
dense CASe bulk nanomaterials for solid state TE energy conversion. By adjusting the amount of extrinsic
dopants, dimensionless TE figures of merit (ZT) up to 1.26 at 673 K were reached. Such high ZT values are
related to an optimized carrier concentration by Sn doping, a minimized lattice thermal conductivity due to
efficient phonon scattering at point defects and grain boundaries, and to an increase of the Seebeck
coefficient obtained by a modification of the electronic band structure with Bi doping. Nanomaterials were
further employed to fabricate ring-shaped TE generators to be coupled to hot pipes, which provided 20
mV and 1 mW per TE element when exposed to a 160 ºC temperature gradient. The simple design and
good thermal contact associated with the ring geometry and the potential low cost of the material solution
processing may allow the fabrication of TE generators with short payback times.