High figure-of-merit for ZnO nanostructures by interfacing lowly-oxidized graphene quantum dots.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 38485943.
- Also identified by DOI 10.1038/s41467-024-46182-2 and PMC identifier 10940299.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Thermoelectric technology has potential for converting waste heat into electricity. Although traditional thermoelectric materials exhibit extremely high thermoelectric performances, their scarcity and toxicity limit their applications. Zinc oxide (ZnO) emerges as a promising alternative owing to its high thermal stability and relatively high Seebeck coefficient, while also being earth-abundant and nontoxic. However, its high thermal conductivity (>40 W m<sup>-1</sup>K<sup>-1</sup>) remains a challenge. In this study, we use a multi-step strategy to achieve a significantly high dimensionless figure-of-merit (zT) value of approximately 0.486 at 580 K (estimated value) by interfacing graphene quantum dots with 3D nanostructured ZnO. Here, we show the fabrication of graphene quantum dots interfaced 3D ZnO, yielding the highest zT value ever reported for ZnO counterparts; specifically, our experimental results indicate that the fabricated 3D GQD@ZnO exhibited a significantly low thermal conductivity of 0.785 W m<sup>-1</sup>K<sup>-1</sup> (estimated value) and a remarkably high Seebeck coefficient of <math xmlns="http://www.w3.org/1998/Math/MathML"><mo>-</mo></math> 556 μV K<sup>-1</sup> at 580 K.