Jian Hao, Xiu Wang, Yanxia Wang, Xiaoyong Lai, Qingjie Guo, Jiupeng Zhao, Yu Yang and Yao Li. Hierarchical structure N, O-co-doped porous carbon/carbon nanotube composite derived from coal for supercapacitors and CO2 capture. Nanoscale Adv., 2020, 2, 878