Biomass Porous Carbon Derived from Celery Leaves with High Capacitance for Supercapacitor

Abstract

To develop environmentally friendly and high‐performance supercapacitors, the low‐cost, high‐capacitance renewable electrode material is at present viewed as one of the most challenging tasks for obtaining the next‐generation of energy storage devices. Therefore, in this study, Celery leaves, a common biomass vegetable, are used to prepare activated carbon for high voltage and high‐capacity supercapacitors through a simple method. Due to their high surface area and abundant nitrogen and sulfur heteroatoms, hierarchically porous carbon materials can simultaneously realize high capacity and long‐cycling durability. The specific capacitance has been recorded to be up to 753.0 F g−1 at 0.5 A g−1 with capacity retention as high as 96.7 % even after 5,000 cycles. Also, the assembled symmetric cell provided a high energy density of 17.36 Wh kg−1 at 250 W kg−1. The effects of yellow and green colors and different activation temperatures on the properties of electrode materials were systematically studied. The results showed an excellent electrochemical performance in biomass carbon electrode materials, which would facilitate the development of a high‐quality energy system and a green supercapacitor.

MnO2 Nanoparticle‐Loaded Self‐Doped (N/O) Porous Carbon Derived from Orychophragmus Violaceus for Application as a High‐Performance Supercapacitor

“…In Figure 4a, three peaks corresponding to C 1s, N 1s, and O 1s can be seen to be detected at 284.00 eV, 400.00 eV and 532.00 eV, respectively, indicating presence of the elements C, N, and O in OPC. [20,21] It can be observed from the figure that OPC@MnO 2 32 in addition to the peaks of C 1s, N 1s and O 1s, there are also peaks of Mn 2p, which suggests that the sample also has the element Mn. Compared to OPC, the C 1s, N 1s and O 1s peaks of OPC@MnO 2 32 all decreased, due to the presence of Mn and the consumption when redox reactions occur.…”

Two biomass material-derived self-doped (N/O) porous carbons from waste coriander and lilac with high specific surface areas and high capacitance for supercapacitors

“…Hysteresis loops in both the isotherms in the range of 0.5 and 1 for P / P 0 indicate the occurrence of capillary condensation. 17 The significantly wider hysteresis loop of LPC-600 compared to that of CPC-600 indicates the presence of more mesopores in LPC-600. 25 Finally, under high pressure, a slight increase in the N 2 adsorption of the two suggests the presence of macropores in both the materials.…”

“…Sufficient active sites are provided for ion adsorption due to the presence of micropores which is conducive for increasing the capacitance, and the kinetic process of ion diffusion can be accelerated by the increased number of mesopores and thereby promoting ion transport. 17,22 Macropores can store electrolytes, thereby shortening the electrolyte transfer path. 29 In short, the two porous carbon materials with a large pore size and high specific surface area are beneficial for obtaining high electrical storage properties.…”

“…15 At the same time, the C s of the material is also increased due to the additional pseudo-capacitance provided due to the presence of N and O heteroatoms. 16,17 A number of heteroatoms like N, O, P and S are present in the biomass. During the carbonization process, organic matter will decompose in large quantities during the carbonization process resulting in the escape of CO 2 via combination of C and O.…”

Multi‐Dimensional Binary Micro CuCo2O4/Nano NiCo2S4 for High‐Performance Supercapacitors

“…It is well known that the composition and structure of electrode materials would jointly determine the charge storage capacity. [18][19][20] To make use of the advantages of BTMO and NCS can be summarized as the multi-dimensional design and multicomponent coordinated control, such as three-dimensional CCO@NiMoO 4 core-shell arrays, [13] and ZnCo 2 O 4 @NCS core-shell structure. [21] These materials properties advances depend on structural design to maximize surface area and improve structural stability.…”