Remarkably improving the specific energy of supercapacitor based on a biomass-derived interconnected hierarchical porous carbon by using a newly-developed mixed alkaline aqueous electrolyte with widened operation voltage

Small‐Molecular Crowding Electrolyte Enables High‐Voltage and High‐Rate Supercapacitors

“…Upon subsequent addition of EG molecules, water molecules tend to coordinate with EG to form EG–H 2 O hydrogen bond rather than H 2 OH 2 O hydrogen bond due to the electrostatic and polarization interactions of polar protic agents with water molecules. [ 32 ] These molecular‐level views provide obvious evidence that the H 2 OH 2 O hydrogen bond is perturbed and reconstructed in 95EG‐H 2 O electrolytes.…”

“…By comparison, when the ratio of polar protic molecules increases to a certain extent, water molecules tend to be intertwined between two polar protic molecules. [ 32 ] As the polar protic hydrogen bond network predominant over the water–water interactions, water molecules are confined and engaged into the uniform 3D hydrogen bond network constructed by the EG molecules, leading to a high water decomposing potential and wide ESW of the small‐molecular crowding electrolyte.…”

“…Remarkably, the SC based on EG exhibits a high energy density of 58.7 Wh kg −1 at a power density of 1.4 and 30.3 Wh kg −1 at a power density of 42 kW kg −1 , outperforming those newly reported carbon‐based aqueous symmetric SCs (Figure 4e and Table S3, Supporting Information). [ 31–45 ] The well performance of SC using 95EG‐H 2 O could be mostly ascribed to its wider ESW and higher operation voltage. Long‐term cycling stability is also the key criterion for the practical application of the SC.…”

Biomass‐derived ant colony‐like ion diffused redox porous carbon toward economical and high‐performance quasi‐solid‐state supercapacitor

“…The micropores may develop due to the etching effect of the NaCl on the seaweed surface. 26,27 For comparison studies, the FE-SEM analysis was performed for PSWC-0.1 and PSWC-0.3 as shown in Figure S1. The following results confirm that the concentration of the NaCl affects the surface morphology of the PSWC-x compounds.…”

“…Meanwhile, the FE‐SEM images of the PSWC‐0.2 compound (Figure 2B(i&ii)) exhibits the stable ant colony‐like morphology with enhanced surface roughness and porous structure, resulting in increased SSA. The micropores may develop due to the etching effect of the NaCl on the seaweed surface 26,27 . For comparison studies, the FE‐SEM analysis was performed for PSWC‐0.1 and PSWC‐0.3 as shown in Figure S1.…”