Biomass-Derived Porous Carbons Derived from Soybean Residues for High Performance Solid State Supercapacitors

Abstract

A series of heteroatom-containing porous carbons with high surface area and hierarchical porosity were successfully prepared by hydrothermal, chemical activation, and carbonization processes from soybean residues. The initial concentration of soybean residues has a significant impact on the textural and surface functional properties of the obtained biomass-derived porous carbons (BDPCs). SRAC5 sample with a BET surface area of 1945 m2 g−1 and a wide micro/mesopore size distribution, nitrogen content of 3.8 at %, and oxygen content of 15.8 at % presents the best electrochemical performance, reaching 489 F g−1 at 1 A g−1 in 6 M LiNO3 aqueous solution. A solid-state symmetric supercapacitor (SSC) device delivers a specific capacitance of 123 F g−1 at 1 A g−1 and a high energy density of 68.2 Wh kg−1 at a power density of 1 kW kg−1 with a wide voltage window of 2.0 V and maintains good cycling stability of 89.9% capacitance retention at 2A g−1 (over 5000 cycles). The outstanding electrochemical performances are ascribed to the synergistic effects of the high specific surface area, appropriate pore distribution, favorable heteroatom functional groups, and suitable electrolyte, which facilitates electrical double-layer and pseudocapacitive mechanisms for power and energy storage, respectively.

Application of Octanohydroxamic Acid for Salting out Liquid–Liquid Extraction of Materials for Energy Storage in Supercapacitors

“…Supercapacitors are currently under development for various energy storage applications [ 1 , 2 ]. Investigations in this research area are focused on the synthesis of advanced electrode materials by different fabrication methods [ 3 , 4 , 5 , 6 , 7 , 8 ], optimization of electrolytes [ 9 ], design of nanocomposites [ 10 , 11 , 12 , 13 ], and modeling [ 14 ]. The synthesis of non-agglomerated particles of controlled shape and composition is of particular importance for supercapacitor technology [ 15 , 16 , 17 ].…”

Coconut Shell-Derived Activated Carbon for High-Performance Solid-State Supercapacitors

“…Previous investigations suggest that an increased BET surface area is beneficial for enhancement of electrochemical performance of EDLCs [4,30,31]. Since the surface area of CSC was much lower than that of CSCKs, the CSCKs were chosen as the CSCKs/Ni composites electrodes.…”

“…The primary ways to optimize the energy density of EDLCs are to increase the specific capacitance of the electrode materials and to widen the voltage window. Firstly, the specific capacitance of the electrode materials is closely related to their presented pore surface areas and distributions [4]. Secondly, the voltage window is usually limited by the electrolytes.…”

Biomass: A Renewable Source of Fuels, Chemicals and Carbon Materials

“…For example, soybean residues were used to prepare nitrogen-and-oxygen-co-doped porous carbons with a high surface area (ca. 2000 m 2 /g) and proper porosity (wide micro-/mesopore size distribution) to be used as supercapacitors [11]. The high specific surface area and proper pore-size distribution along with the presence of nitrogen functional groups favored the formation of the electrical double-layer, resulting in materials with outstanding electrochemical performance.…”