Organic Molecular Electrode with Ultrahigh Rate Capability for Supercapacitors
Fuquan Ma, Xiaotong Wang, Zhongai Hu, Lijie Hou, Yuying Yang, Zhimin Li, Yuanyuan He, Hong Zhu
Abstract
This work reports a feasible method to fabricate a novel organic molecule electrode, in which 3,4,9,10-perylenetetracarboxylic acid (PTCA) is immobilized on the surface of reduced graphene oxide (rGO1) by using a noncovalent strategy. In the three-electrode configuration, the specific capacitance for the PTCA/rGO1 electrode is 422.7 F g–1 at 10 mV s–1. More importantly, it can retain 94.6% of the initial value at 100 mV s–1. This ultrahigh rate capability could be put down to ultrafast protonation/deprotonation electrochemical reaction based on the four carboxyl groups in PTCA. To further explore the practical performance of electrode materials, an asymmetric supercapacitor (PANI/rGO2//PTCA/rGO1) is constructed by using PTCA/rGO1 and PANI/rGO2 as the negative and positive electrode, respectively. The device (PANI/rGO2//PTCA/rGO1 ASC) reveals an outstanding energy storage capacity, in which the energy density reaches 14 W h kg–1 along with a power density of 520 W kg–1.