N–O–S Co-doped Hierarchical Porous Carbons Derived from Calcium Lignosulfonate for High-Performance Supercapacitors

Abstract

We propose a simple and low-cost synthesis of N–O–S co-doped hierarchical porous carbons (MGC-x) by direct carbonization of calcium lignosulfonate. MGC-x possesses a large surface area (∼1500 m2 g–1) and high mesopore ratio (>40%) and heteroatom content. In the three-electrode system, MGC-700 and MGC-800 exhibit high specific capacitances of 417 and 312 F g–1 at 0.5 A g–1 and 184 and 170 F g–1 even at 100 A g–1 using a 1 M H2SO4 electrolyte. Notably, there exists a critical current density when evaluating the rate capability of MGC-x electrodes, which is closely correlated to their ion diffusion and electron transport properties. In two-electrode configuration with a 3 M KOH electrolyte, MGC-700 with ultrahigh mass loading (∼13 mg cm–2, ∼210 μm) can deliver large specific capacitance of 249 F g–1 and excellent rate capability with capacitance retention of 81.9% from 0.05 to 20 A g–1. MGC-700 and MGC-800 both show superb cycling stabilities with 94 and 98% of original capacitances being retained after 10 000 cycles, respectively. Furthermore, the MGC-700-based supercapacitor with commercial-level electrode mass loading yields an impressive energy density of 7.2 Wh kg–1 at 62.5 W kg–1 and maintains 5.1 Wh kg–1 even at 4585.4 W kg–1. The MGC-800-based supercapacitor exhibits considerable energy densities of 26.7 and 9.8 Wh kg–1 at 309.8 and 7000 W kg–1 in a 1 M (C2H5)4NBF4/PC electrolyte, respectively, guaranteeing its utilization in high-performance supercapacitors.

Green Synthesis of Nitrogen-doped Porous Carbon Derived from Rice Straw for High-performance Supercapacitor Application

“…Here, the I D / I G ratios of AC-KB-X (X = 2, 4, 6), AC-KOH, and AC-KB-M were calculated to be 1.02, 1.07, 1.10, 1.11, and 1.12, respectively. The higher I D / I G ratio suggests more defects and a high degree of disorder in PCs, which agree with the XRD analysis. , …”

“…The higher I D /I G ratio suggests more defects and a high degree of disorder in PCs, which agree with the XRD analysis. 35,46 To investigate the effect of the added melamine on introducing N-species, surface chemical composition was measured by XPS. As shown in Figure 2e, although N element is detected in AC-KB-6, the N 1s peak of AC-KB-M is much higher, signifying that the N element was successfully introduced into the carbon matrix by adding melamine.…”

Facile Preparation of Low-Cost and Cross-Linked Carbon Nanofibers Derived from PAN/PMMA/Lignin as Supercapacitor Electrodes

“…The XPS survey of N 1s could be classified into three peaks at 398, 399.7, and 400.8 eV, which are assigned to pyridinic N, pyrrolic/pyridinic N, and quaternary N, respectively., with a relative content of 42.4%, 20.2% and 37.4%, respectively. Pyridine N and pyrrole N could provide active sites for electrochemical reactions and increase electrode specific capacitance. − …”

Construction of Functionalized Carbon Nanofiber–g-C3N4 and TiO2 Spheres as a Nanostructured Hybrid Electrode for High-Performance Supercapacitors

“…Energy sources such as fossil fuels, used in the energy sectors, are finite resources that cause pollution and will eventually be depleted. Hence, it is imperative to develop proficient energy conversion and storage apparatuses to supply or substitute clean, renewable, and defensible energy. , In this respect, energy storage devices, such as supercapacitors and batteries, are important because of their superior efficiency, stability, and eco-friendly nature. − Supercapacitors, also called electrochemical and ultra supercapacitors, principally work on a charging and discharging process. The process occurs mainly between the two plates based on applying the external charges (positive and negative); it also encourages the potential difference between the plates.…”

“…Hence, it is imperative to develop proficient energy conversion and storage apparatuses to supply or substitute clean, renewable, and defensible energy. 1,2 In this respect, energy storage devices, such as supercapacitors and batteries, are important because of their superior efficiency, stability, and eco-friendly nature. 3−5 Supercapacitors, also called electrochemical and ultra supercapacitors, principally work on a charging and discharging process.…”