Thermoelectric generators (TEGs) based on thermogalvanic cells can convert low-temperature waste heat into electricity. Organic redox couples are well-suited for wearable devices due to their nontoxicity and the potential to enhance the ionic Seebeck coefficient through functional-group modifications. Pyrazine-based organic redox couples with different functional groups is comparatively analyzed through cyclic voltammetry under varying temperatures. The results reveal substantial differences in entropy changes with temperature and highlight 2,5-pyrazinedicarboxylic acid dihydrate (PDCA) as the optimal candidate. How the functional groups of the pyrazine compounds impact the ionic Seebeck coefficient is examined, by calculating the electrostatic potential based on density functional theory. To evaluate the thermoelectric properties, PDCA is integrated in different concentrations into a double-network hydrogel comprising poly(vinyl alcohol) and polyacrylamide. The resulting champion device exhibits an impressive ionic Seebeck coefficient (S) of 2.99 mV K, with ionic and thermal conductivities of ≈67.6 µS cm and ≈0.49 W m K, respectively. Finally, a TEG is constructed by connecting 36 pieces of 20 × 10 m PDCA-soaked hydrogel in series. It achieves a maximum power output of ≈0.28 µW under a temperature gradient of 28.3 °C and can power a small light-emitting diode. These findings highlight the significant potential of TEGs for wearable devices.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/smll.202407622 | DOI Listing |
Environ Sci Technol
January 2025
National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China.
Methylmercury in paddy soils poses threats to food security and thus human health. Redox-active phenolic and quinone moieties of natural organic matter (NOM) mediate electron transfer between microbes and mercury during mercury reduction. However, their role in mercury methylation remains elusive.
View Article and Find Full Text PDFChem Commun (Camb)
January 2025
Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, Yunnan Provincial Center for Research & Development of Natural Products, School of Pharmacy, Yunnan University, Kunming, 650091, P. R. China.
In recent years, visible light-induced ligand-to-metal charge transfer (LMCT) has emerged as an attractive approach for synthesizing a range of functionalized molecules. Compared to conventional photoredox reactions, photoinduced LMCT activation does not depend on redox potential and offers diverse reaction pathways, making it particularly suitable for the activation of inert bonds and the functional modification of complex organic molecules. This review highlights the indispensable role of photoinduced LMCT in synthetic chemistry, with a focus on recent advancements in LMCT-mediated hydrogen atom transfer (HAT), C-C bond cleavage, decarboxylative transformations, and radical ligand transfer (RLT) reactions.
View Article and Find Full Text PDFNano Lett
January 2025
Second Physics Institute, University of Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany.
Conducting polymers have emerged as promising active materials for metasurfaces due to their electrically tunable states and large refractive index modulation. However, existing approaches are often limited to infrared operation or single-polymer systems, restricting their versatility. In this Letter, we present organic metasurfaces featuring dual conducting polymers, polyaniline (PANI) and poly(3,4-ethylenedioxythiophene) (PEDOT), to achieve contrasting dynamic optical responses at visible frequencies.
View Article and Find Full Text PDFLangmuir
January 2025
School of Chemistry and Chemical Engineering, Lanzhou Jiaotong University, Lanzhou 730070, P. R. China.
Cobalt-based metal-organic framework (MOFs)-derived catalysts are acknowledged for their effectiveness in activating peroxymonosulfate (PMS) for the treatment of persistent pollutants. However, the limited adsorption of PMS on the catalyst surface markedly reduces its degradation efficiency. To overcome this limitation, nanoflower-like EuO/CoO-0.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!