Choi, Yoohyeon Tran, Ngoc Tuan Jang, Doojoon Park, Minju Yoo, Chun-Jae Kim, Jin Young Lee, Hyunjoo Kim, Heesuk 2024-01-19T08:01:08Z 2024-01-19T08:01:08Z 2023-12-21 2024-01 1463-9262 https://pubs.kist.re.kr/handle/201004/112966 As global interest in carbon-neutrality policies grows, the demand for sustainable alternatives to fossil fuels intensifies. Herein, we demonstrate functionalized lignin-based n- and p-dopants for nanocarbon materials, providing promising eco-friendly alternatives to chemical dopants derived from fossil fuels. A simple microwave-assisted phenolation of organosolv lignin introduces phenol groups, offering additional reaction sites and enhancing solvent solubility for uniform, reliable and efficient carbon nanotube (CNT) doping. To create effective n- and p-dopants, the phenolated lignin is further functionalized with amine and hexafluoropropyl groups, respectively. The aminated and fluorinated lignin-doped CNTs present the Seebeck coefficients of -48.0 and 53.9 mu V K-1, respectively, confirming an efficient and eco-friendly conversion between n- and p-type CNT. Notably, this n-doping performance is of particular significance since stable and reliable n-doping is challenging due to the inherent p-type semiconducting properties of CNTs. As a proof of concept, we demonstrate a flexible thermoelectric generator using 10 p-n pairs of the CNT films. The output voltage (7.86 mV) and output power (247 nW) of the flexible generator at Delta T = 15 K confirm that the aminated- and fluorinated lignin-doped CNT films exhibit n- and p-type characteristics, respectively. This study paves the way for sustainable, lignin-based doping of carbon nanomaterials, offering a green alternative to traditional fossil fuel-derived dopants and contributing to the transition towards carbon-neutral technologies. We strategically modify lignin as effective p- and n-dopants for nanocarbon materials, offering promising alternatives to chemical dopants from fossil-fuels. English Royal Society of Chemistry Eco-friendly conversion between n- and p-type carbon nanotubes based on rationally functionalized lignin biopolymers Article 10.1039/d3gc03944g 1 Green Chemistry, v.26, no.1, pp.330 - 339 Green Chemistry 26 1 330 339 N scie scopus 001119541000001 Chemistry, Multidisciplinary Green & Sustainable Science & Technology Chemistry Science & Technology - Other Topics Article CORROSION INHIBITION MANNICH REACTION MILD-STEEL PHENOLATION TRANSPORT KRAFT