A Holey Graphene Additive for Boosting Performance of Electric Double-Layer Supercapacitors

Jun-Bin Huang, Jagabandhu Patra, Ming-Hsien Lin, Ming-Der Ger, Yih-Ming Liu, Nen-Wen Pu, Chien-Te Hsieh, Meng-Jey Youh, Quan-Feng Dong, Jeng-Kuei Chang
2020 Polymers  
We demonstrate a facile and effective method, which is low-cost and easy to scale up, to fabricate holey graphene nanosheets (HGNSs) via ultrafast heating during synthesis. Various heating temperatures are used to modify the material properties of HGNSs. First, we use HGNSs as the electrode active materials for electric double-layer capacitors (EDLCs). A synthesis temperature of 900 °C seems to be optimal, i.e., the conductivity and adhesion of HGNSs reach a compromise. The gravimetric
more » ... ravimetric capacitance of this HGNS sample (namely HGNS-900) is 56 F·g−1. However, the volumetric capacitance is low, which hinders its practical application. Secondly, we incorporate activated carbon (AC) into HGNS-900 to make a composite EDLC material. The effect of the AC:HGNS-900 ratio on the capacitance, high-rate performance, and cycling stability are systematically investigated. With a proper amount of HGNS-900, both the electrode gravimetric and volumetric capacitances at high rate charging/discharging are clearly higher than those of plain AC electrodes. The AC/HGNS-900 composite is a promising electrode material for nonaqueous EDLC applications.
doi:10.3390/polym12040765 pmid:32244627 fatcat:4mbnpgnhlrakhbojumivgykg7m