Stretchable and Durable Bacterial Cellulose-Based Thermocell with Improved Thermopower Density for Low-Grade Heat Harvesting

• Published in: Nano letters Vol. 23; no. 22; pp. 10297 - 10304
• Main Authors: Wu, Zhuotong, Wang, Baoxiu, Li, Jing, Jia, Yuhang, Chen, Shiyan, Wang, Huaping, Chen, Lihui, Shuai, Li
• Format: Journal Article
• Language: English
• Published: 22-11-2023
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/acs.nanolett.3c02870

Low-grade heat exists ubiquitously in the environment, and gel-state thermogalvanic cells (GTCs) can directly convert thermal energy into electricity by a redox reaction. However, their low ionic conductivity and poor mechanical properties are still insufficient for their potential applications. Here, we designed a bacterial cellulose (BC) nanofiber-macromolecular entanglement network to balance the GTC's thermopower and mechanical properties. Therefore, the BC-GTC shows a Seebeck coefficient of 3.84 mV K-1, an ionic conductivity of 108.5 mS cm-1, and a high specific output power density of 1760 μW m-2 K-2, which are much higher than most current literature. Further connecting 15 units of BC-GTCs, the output voltage of 3.35 V can be obtained at a temperature gradient of 65 K, which can directly power electronic devices such as electronic calculators, thermohydrometers, fans, and light-emitting diodes (LEDs). This work offers a promising method for developing high-performance and durable GTC in sustainable green energy.