Understanding Thermal and Charge Transport in Inorganic, Hybrid, and Organic Thermoelectric Materials
ORAL · Invited
Abstract
Optimizing thermal and charge transport within thermoelectric materials is essential for sustainable energy harvesting. This presentation details our progress in deepening the physical understanding of these transport mechanisms across a diverse spectrum of inorganic, hybrid, and organic thermoelectric materials.
Beginning with high-performance inorganic materials, we resolve anomalous thermal conductivity behavior of cubic GeTe by combining inelastic X-ray scattering and high-order machine-learned models. In parallel, we demonstrate single-crystal SnSe fibers achieving a record ZT of ~2 at 862 K.
Moving into the hybrid regime, we carry out both experimental and computational studies on the thermal transport of 2D hybrid perovskite BA2PbI4, reporting ultralow thermal conductivity (< 0.3 W/m·K) with a remarkably weak anisotropy ratio (~1.5), offering a pathway to minimize lattice thermal conductivity and highlighting its potential for high-efficiency thermoelectric devices.
Transitioning to the organic regime, we develop freestanding, micrometer-thick PEDOT:PSS films with a thermoelectric power factor of 204 µW/(m·K2), offering high-efficiency solutions for flexible energy harvesting and storage. Moreover, we combine polymer-dopant grafting (PEI) with surfactant-functionalization (DODMAC) to overcome n-type single-walled carbon nanotube (SWCNT) bottlenecks on charge localization and oxidation, yielding a 12-fold conductivity increase. PEI bridging enables unusual band-like conduction and long-term stability via enhanced inter-tube van der Waals contacts.
At the device level, we transform the conventional in-plane architecture of organic thermoelectric devices into a cross-plane configuration using an innovative rolling technique. This geometry significantly boosts power output by enlarging conduction pathways and integrating thermally conductive substrates.
Together, these studies provide a pathway for the next generation of efficient thermoelectric energy conversion systems.
Beginning with high-performance inorganic materials, we resolve anomalous thermal conductivity behavior of cubic GeTe by combining inelastic X-ray scattering and high-order machine-learned models. In parallel, we demonstrate single-crystal SnSe fibers achieving a record ZT of ~2 at 862 K.
Moving into the hybrid regime, we carry out both experimental and computational studies on the thermal transport of 2D hybrid perovskite BA2PbI4, reporting ultralow thermal conductivity (< 0.3 W/m·K) with a remarkably weak anisotropy ratio (~1.5), offering a pathway to minimize lattice thermal conductivity and highlighting its potential for high-efficiency thermoelectric devices.
Transitioning to the organic regime, we develop freestanding, micrometer-thick PEDOT:PSS films with a thermoelectric power factor of 204 µW/(m·K2), offering high-efficiency solutions for flexible energy harvesting and storage. Moreover, we combine polymer-dopant grafting (PEI) with surfactant-functionalization (DODMAC) to overcome n-type single-walled carbon nanotube (SWCNT) bottlenecks on charge localization and oxidation, yielding a 12-fold conductivity increase. PEI bridging enables unusual band-like conduction and long-term stability via enhanced inter-tube van der Waals contacts.
At the device level, we transform the conventional in-plane architecture of organic thermoelectric devices into a cross-plane configuration using an innovative rolling technique. This geometry significantly boosts power output by enlarging conduction pathways and integrating thermally conductive substrates.
Together, these studies provide a pathway for the next generation of efficient thermoelectric energy conversion systems.
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Publication: 1. Nat. Commun. 2024, 15, 6981.
2. Adv. Mater. 2020, 32, 2002702.
3. Nano Lett. 2021, 21, 3708–3714.
4. ACS Appl. Energy Mater. 2025, 8, 25–30.
5. Small Methods 2024, 8, 2400585.
Presenters
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Chen Li
- Cornell University