Hierarchically porous and heteroatom doped carbon derived from tobacco rods for supercapacitors

A novel tobacco rods-derived carbon (TC) has been prepared by hydrothermal carbonization and potassium hydroxide activation strategy for supercapacitors application. The physicochemical properties of TC are investigated by X-ray diffraction, Raman spectra, Scanning electron microscopy, Nitrogen adsorption-desorption isotherms, X-ray photoelectron spectroscopy, and four-probe tests. Results show TC derived from different tobacco rods possesses similar properties, such as amorphous state, high specific surface area, hierarchical porous structure, numerous heteroatom groups, and good electrical conductivity. The electrochemical characteristics of TC are examined via cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy measurements. In a three electrode system, TC exhibits high capacitance with 286.6 F g(-1) at 0.5 A g(-1), excellent rate performance with 212.1 F g(-1) even at 30 A g(-1), and outstanding cyclic stability with 96% capacitance retention after 10,000 cycles at 5 A g(-1). Furthermore, TC supercapacitor devices can deliver an energy density of 313 Wh kg(-1) at 0.5 A g(-1) and power density of 11.8 kW kg(-1) at 15 A g(-1). Therefore, this novel concept of tobacco use, namely tobacco rods from cigarette (the harmful) to high-performance carbon for super capacitors (the beneficial), is an extremely promising strategy for developing high-performance carbon from renewable sources, and supporting the tobacco control. (C) 2016 Elsevier B.V. All rights reserved.