High-capacitance activated bio-carbons with controlled pore size distribution for sustainable energy storage

다국어 초록 (Multilingual Abstract)

<P><B>Abstract</B></P> <P>Depletion of fossil-fuel energy resources creates a demand for sustainable energy technologies and therefore necessitates the development of sustainable energy storage devices with sustainable materials, eco-efficient synthetic methods, and robust cycle life. Electric double layer capacitors are potential candidates for sustainable energy storage because they usually employ carbon-based electrode materials with semi-permanent lifetimes and high powers. Although various carbon materials are commercially available, new methods are needed to produce eco-efficient synthesized carbon materials with high performances. Herein, we introduce an effective strategy that uses biomaterials as carbon sources and adopts a reusable KOH solution soaking method for the activation process to reduce KOH consumption, which includes a pore-size control process to enhance electrochemical performances. The obtained bio-carbons exhibit specific capacitances (160.6 and 151.2 F g<SUP>−1</SUP> in aqueous and organic electrolytes, respectively) superior to that of commercially available activated carbon (~80 F g<SUP>−1</SUP>), which is attributed to the synergetic effect between the pore-size-controlled activated carbon for efficient ion transport and the well-matched electrolyte. Our strategy provides a versatile method for the scalable fabrication of sustainable energy storage materials and is promising for the development of high-performance supercapacitors.</P> <P><B>Highlights</B></P> <P> <UL> <LI> •Activated bio-carbons for sustainable energy storage were prepared </LI> <LI> •Physical properties of the pore-size controlled materials were evaluated </LI> <LI> •Activated carbon electrodes were applied in electric double-layer capacitors </LI> <LI> •The electrodes showed excellent capacitance in aqueous and organic electrolytes </LI> <LI> •The large specific surface area and ion-matched pore size were key to performance </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>