In:
Energy Technology, Wiley, Vol. 8, No. 3 ( 2020-03)
Abstract:
Soybean shell (SS), as the byproduct of soybeans, is converted into porous carbon (PC) with a high specific surface area (SSA) via hydrothermal carbonization with H 3 PO 4 followed by KOH activation. No obvious effect on the crystal structure of PC can be found by addition of H 3 PO 4 during the hydrothermal process. However, the SSA of PC increases remarkably compared with hydrothermal carbonization without H 3 PO 4 , as H 3 PO 4 assists in hydrothermal carbonization dehydration reactions and creates some pores beneficial for KOH activation. The SSA of the obtained PC reaches 2523 m 2 g −1 , and the hierarchical pore structure is mainly in 0.6–50 nm. The sample prepared by hydrothermal carbonization with 10 wt% H 3 PO 4 and activation by KOH with the ratio of KOH/10‐hydrochar 3 under 700 °C exhibits a specific capacitance of 301 F g −1 in 6 m KOH electrolyte at the current density of 0.1 A g −1 . It also has an excellent cycling stability with the specific capacitance remaining at 93.8% after 15 000 cycles. Furthermore, the energy density is 8.1 Wh kg −1 in the two‐electrode system. These results display that PC based on SS is a promising electrode material for the electric double‐layer capacitor.
Type of Medium:
Online Resource
ISSN:
2194-4288
,
2194-4296
DOI:
10.1002/ente.201901103
Language:
English
Publisher:
Wiley
Publication Date:
2020
detail.hit.zdb_id:
2700412-0
Permalink