5 years ago

High capacitance and energy density supercapacitor based on biomass-derived activated carbons with reduced graphene oxide binder

High capacitance and energy density supercapacitor based on biomass-derived activated carbons with reduced graphene oxide binder
Reduced graphene oxide (RGO) is employed as a conductive binder for the unprecedentedly high performance of the used coffee grounds-derived AC (cAC) supercapacitor. The 2 wt% of RGO sheets in the cAC based electrode (cAC-2) successfully preserves high specific surface area of cAC and supports conductive networks decorated with oxygen groups, which synergistically improve charge storage capability. Furthermore, the wettability of the cAC-2 electrode enhanced by hydrophilic oxygen groups of RGO allows the easy access of the electrolyte to the pores of the electrode. The symmetric two electrode system exhibits outstanding charge storage capacity, reaching a high specific capacitance of 512 F g−1 in KOH electrolyte at 0.5 A g−1 which is nearly four times higher than that of cAC electrode with PVDF binders. Remarkable electrochemical performance is further demonstrated in EMIMTFSI electrolyte, including high specific capacitance of 440 F g−1 at 0.5 A g-1, with an excellent rate performance of 81.4% from 0.5 to 10 A g-1. The record high energy density of 187.3 Wh kg−1 is achieved at a power density of 438 W kg−1 and maintains an energy density of 153.8 Wh kg−1 at 8750 W kg−1 in EMIMTFSI electrolyte.

Publisher URL: www.sciencedirect.com/science

DOI: S0008622318301143

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.