Enhanced Thermoelectric Performance of PVA-Based Ionogels: Tailoring Crystallinity via Additives for Advanced Waste Heat Recovery
Converting low-grade waste heat into electricity is crucial for green energy. This study introduces an innovative approach using poly(vinyl alcohol) (PVA)-based ionogels incorporating 1-ethyl-3-methylimidazolium dicyanamide ([EMIM][DCA]) and specific additives: 2-carboxyphenylacetic acid (H), 2-sulfobenzoic acid (S), and 2-carboxyphenyl phosphate (P)). These additives enable successful tailoring of the crystallinity, leading to a substantial increase in the ionic figure-of-merit (z<i>T</i><sub>i</sub>), from 0.006 for the PVA ionogel to 0.27 for the ionogel with P additives. Furthermore, the P-additive ionogels exhibit excellent mechanical properties, with a tensile stress of 1.75 MPa and a strain of 460%. A four-pair ionic thermoelectric capacitor made from these ionogels generates 0.33 V and achieves a power output of 2.4 mW m<sup>-2</sup>. This advancement significantly improves the thermoelectric performance of PVA ionogels, aiding in efficient waste heat utilization and sustainable energy development.
Authors
- Keun Hyung Lee (ORCID: https://orcid.org/0000-0003-4066-9991)
- U‐Ser Jeng (ORCID: https://orcid.org/0000-0002-2247-5061)
- Cheng‐Liang Liu (ORCID: https://orcid.org/0000-0002-8778-5386)
- Shao‐Huan Hong
- Ling‐Chieh Lee
- Shih‐Huang Tung (ORCID: https://orcid.org/0000-0002-6787-4955)
- Minsu Kim (ORCID: https://orcid.org/0000-0001-6277-2039)
- Chia-Hsin Wang
Institutions
- National Taiwan University (TW)
- Inha University (KR)
- National Synchrotron Radiation Research Center (TW)
Publication Details
- Journal
- ACS Applied Materials & Interfaces
- Published
- 2025-06-21
- DOI
- https://doi.org/10.1021/acsami.5c08724
- Citations
- 5
- Primary Topic
- Advanced Thermoelectric Materials and Devices
- Type
- article
- Field-Weighted Citation Impact
- 2.59
Funders
- National Taiwan University
- National Science and Technology Council