Chemically modified self-doped biocarbon via novel sulfonation assisted sacrificial template method for high performance flexible all solid-state supercapacitor Qidu Deng a,1 , Syed Comail Abbas a,1 , Zeliang Li a , Jiangquan Lv c , Xiaojuan Ma a,⇑ , Shilin Cao a,⇑ , Yonghao Ni a,b , Weigang Zhao a,⇑ a College of Materials Engineering, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China b Department of Chemical Engineering, University of New Brunswick, Fredericton, New Brunswick E3B5A3, Canada c College of Electronics and Information Science & Organic Optoelectronics Engineering Research Center of Fujian’s Universities, Fujian Jiangxia University, Fuzhou, Fujian 350108, China graphical abstract article info Article history: Received 29 January 2020 Revised 6 April 2020 Accepted 6 April 2020 Available online 7 April 2020 Keywords: Chemical modification Biocarbon materials Sacrificial template Sulfonation abstract The development of lignin-based carbon electrodes for high-performance flexible, solid-state supercapac- itors in next-generation soft and portable electronics, has received much attention. Herein, a self-doped multi-porous lignin-based biocarbon (SUMBC) has been prepared via a simple sulfonation assisted sacri- ficial template method for the effective formation of oxygenated C-S-C moieties in the carbon network. In this proposed method, the sulfonate moieties in lignin are responsible for the successful decoration of oxygen enriched C-S-C moieties as well as for creating the optimal multilevel porous architecture (ultra-micropores, micropores and mesopores) in the carbon matrix with a large surface area (3149 m 2 g 1 ). Because the sulfonate functionalities yield more sulfur species and induce further defects into car- bon framework, in the activation process, these sulfur functionalities produce additional narrow micro- pores. Benefiting from the above unique feature, the supercapacitor (SC) with the SUMBC electrode https://doi.org/10.1016/j.jcis.2020.04.029 0021-9797/Ó 2020 Elsevier Inc. All rights reserved. ⇑ Corresponding authors. E-mail addresses: 1212juanjuan@163.com (X. Ma), scutcsl@163.com (S. Cao), weigang_zhao@fafu.edu.cn (W. Zhao). 1 These authors contributed equally. Journal of Colloid and Interface Science 574 (2020) 33–42 Contents lists available at ScienceDirect Journal of Colloid and Interface Science journal homepage: www.elsevier.com/locate/jcis