Porous carbon nanosheets from coal tar pitch for zinc ion hybrid capacitor

Abstract

As a by-product of coal chemical industry, it is very suitable to be used as carbon precursor to prepare carbon materials because of its rich aromatic hydrocarbons. However, the preparation of carbon materials often uses a lot of metal oxides and strong alkali, which will not only cause corrosion to the equipment, but also produce wastewater. Herein, the mixture of bicarbonate and hydrogen oxalate was used as template and activator to synthesize porous carbon nanosheets, which presents high speci c surface area of 784.8 m 2 g − 1 and multiple ion transport channels. Due to those merits, the PCNS 2 cathode displays superior zinc ion storage performance, such as high speci c capacity of 210.1 F g − 1 , excellent energy density and power output of 83.3 Wh kg − 1 and 17.2 kW kg − 1 and long cycle life with capacity retention of 98.57% after 11000 cycles. This work provides an avenue to prepare porous carbon nanosheets for energy storage devices.