Hybrid supercapacitors: A simple electrochemical approach to determine optimum potential window and charge balance

Highly Stable Supercapacitor Devices Based on Three-Dimensional Bioderived Carbon Encapsulated g-C3N4 Nanosheets

“…Whereas the strongest peak at 398.48 ± 0.05 eV is ascribed to pyridinic nitrogen, the three other peaks at 399.1 ± 0.05, 400.9 ± 0.05, and 404.1 ± 0.05 eV can be assigned to tertiary nitrogen (N− C), amino nitrogen (N−H), and nitrogen-oxide group, respectively. 27,46 Upon the addition of biocarbon, the pyridinic and tertiary nitrogen content increased by 0.3 and 2.62%, respectively and the nitrogen-oxide and amino nitrogen decreased by ∼0.24% and 2.65%, respectively. The pyridinic and tertiary nitrogen, which have a high electron density and electron donating properties are responsible for pseudocapacitive nature in electrochemical 47 and biocarbon additive increase the contribution of both species.…”

“…To investigate the real performance of the GCN/Bio-C20 electrode, an asymmetric supercapacitor device (ASC) was assembled using mesoporous nitrogen-doped carbon (MPNDC) negative electrode 27 with a high specific surface area (1424 cm 2 g −1 ), see the Supporting Information Figure S8. The CV of the MPNDC (see Figure 7a) electrode in the window of −0.6 to 0 V vs SCE showed a quasi-rectangular shape.…”

“…Then, the powders were filtered and washed several times using distilled water and finally dried at 80 °C. The Palm loofah fiber derived activated carbon (Bio-C) and mesoporous nitrogen-doped carbon (MPNDC) were synthesized according to previous reports, , as briefly described in the Supporting Information. To prepare the GCN/biocarbon composite, the Bio-C was added in different contents and the formed composite was named GCN/Bio-Cx, which x is the given Bio-C content.…”

“…23 Unfortunately, the low surface area and low electronic conductivity of GCN usually result in sluggish ions/electrons transfer kinetics, restricting its use to construct efficient energy storage devices. 24−26 Consequently, many efforts have been made to expand its energy storage features 27 nanofibers, 18 carbon nanotubes, 28 and nitrogen-doped carbon spheres. 29 However, the stated capacitance up to now is still low compared to other carbon materials with no given correlation between the reported capacitance values and the effect of combined material(s).…”

“…Recently, GCN has been investigated as a capable carbon-based material for energy storage applications due to the presence of nitrogen heteroatom in its chemical structure, which improves its capacitance, provides mixed charge storage mechanisms, and increases its surface reactivity over the undoped carbon counterparts . Unfortunately, the low surface area and low electronic conductivity of GCN usually result in sluggish ions/electrons transfer kinetics, restricting its use to construct efficient energy storage devices. − Consequently, many efforts have been made to expand its energy storage features by its combination with other carbon materials such as mesoporous doped carbon, nanofibers, carbon nanotubes, and nitrogen-doped carbon spheres . However, the stated capacitance up to now is still low compared to other carbon materials with no given correlation between the reported capacitance values and the effect of combined material(s).…”