Tannic acid modified graphene/CNT three-dimensional conductive network for preparing high-performance transparent flexible heaters

• Published in: Journal of colloid and interface science Vol. 577; pp. 300 - 310
• Main Authors: Wang, Tao, Jing, Li-Chao, Zhu, Qingxia, Sagadevan Ethiraj, Anita, Fan, Xiaowei, Liu, Hao, Tian, Ying, Zhu, Zeru, Meng, Zhili, Geng, Hong-Zhang
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.10.2020
• Subjects: Carbon nanotubes; Embedded structure; Graphene; Transparent flexible heaters; Waterborne polyurethane; Carbon nanotubes; Embedded structure; Waterborne polyurethane; Graphene; Transparent flexible heaters
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/j.jcis.2020.05.084

The high-adhesion and ultralow-roughness TG/TCNT/PEDOT-WPU TCFs with an embedded structure can be used as high performance TFHs. [Display omitted] •TA can be used as a modifier for CNTs, and a stripping medium to exfoliated graphite to graphene by microfluidization.•High-adhesion and ultralow-roughness TCFs were fabricated by embedding conductive network in WPU.•For TFHs, the temperature increased rapidly and reached a steady state within 20 s when applied voltage. In this paper, the eco-friendly plant polyphenol, tannic acid (TA) was demonstrated as a non-covalent modifier for carbon nanotubes (CNTs), as well as a stripping medium to achieve exfoliated graphite to graphene by microfluidization. High-performance transparent flexible heater (TFH) with an embedded structure had been successfully fabricated by integrating conductive nanocomposites (TA-functionalized grapheme/TA-functionalized CNT/PEDOT:PSS; TG/TCNT/PEDOT) into waterborne polyurethane (WPU) film. Such a film exhibited favorable optical transmittance and sheet resistance (T = ca. 80% at 550 nm, Rs = 62.5 Ω/sq.), low root mean square (rms) roughness (approximately 0.37 nm), excellent adhesion and mechanical stability (the sheet resistance remained almost constant after 1000 bending cycle test for the bending radius of 10 mm), which are ideal as transparent heaters with high thermal efficiency. For TG/TCNT/PEDOT-WPU TFHs, the temperature increased rapidly and reached a steady state within 20 s with the maximum temperature reached to 116 °C, when the applied voltage was 20 V. Moreover, no variation in temperature was observed after the repeated heating–cooling tests and long-time stability test, indicating that TG/TCNT/PEDOT-WPU TCFs can be used as high performance TFHs. These TFH’s are expected to be suitable for vehicle defrosting, smart windows, portable heating, smart wearable devices, etc.