Porous Carbon Composite Generated from Silk Fibroins and Graphene for Supercapacitors

Abstract

Hierarchical porous heteroatom-doped carbon composites were developed by carbonization followed by KOH activation process, with natural silkworm cocoon and chemical exfoliated graphene sheets as starting materials. The introduction of graphene sheets offers more hierarchical micro/meso porosities, a low charge-transfer resistance, and a large BET surface area of ∼1281.8 m 2 g –1 , which are responsible for the fast charge/discharge kinetics and the high rate capability compared with those of single silk fibroins-derived carbon materials. The silk fiber provides a high level of heteroatom functionalities (∼2.54% N and ∼21.3% O), which are desirable for high faradaic pseudocapacitance. The as-prepared carbon composite exhibited a high specific capacitance of 290 F g –1 with good rate capability and cycling stability. The symmetric supercapacitors yielded a high value of energy density of 12.9 W h kg –1 at a power density of 95 W kg –1 with a 1.45 V voltage range in 1 M KOH aqueous electrolytes.

Recent advancements in 3D porous graphene-based electrode materials for electrochemical energy storage applications

“…nickel foam disk. Similarly, Zhou et al studied the symmetric capacitance of porous graphene/ composite using activated silk cocoon fibroins/exfoliated graphene (represented as KCC) as a starting material [98]. The as-prepared silk-derived carbon material was pyrolyzed and then chemically activated with KOH at different temperatures.…”

“…Similarly, Zhou et al studied the symmetric capacitance of porous graphene/composite using activated silk cocoon fibroins/exfoliated graphene (represented as KCC) as a starting material. 98 The as-prepared silk-derived carbon material was pyrolyzed and then chemically activated with KOH at different temperatures. The reported specific surface area of the optimal composite material was 1281.8 m 2 g −1 and exhibited a specific capacitance of 290 F g −1 at an applied current density of 0.2 A g −1 (refer to Table 3).…”

Advances in Preparation and Properties of Regenerated Silk Fibroin

“…Silk fibroin can be converted into water-soluble regenerated silk fibroin protein (RSF) through a series of treatments. Under specific conditions, RSF solutions can be processed into films, sponges, microspheres, gels, and nanofibers for various applications [7], including biomedicine [8][9][10] (e.g., drug delivery carriers, wound dressings, and tissue adhesion), tissue engineering [11][12][13] (e.g., tissue scaffolds), food processing [14,15] (e.g., food additives and packaging), effluent treatment [16] (e.g., water filtration membranes), optics [17,18] (e.g., nanolithography and optical fibers), electrochemistry [19][20][21] (e.g., electrocatalytic materials, supercapacitors, and nanogenerators), and biosensing [22,23] (e.g., flexible wearable sensors and human-machine interaction).…”

In situ preparation of molybdenum-dioxide-incorporated carbonized silk fiber and its application in supercapacitors

“…It is noteworthy that N doping can effectively enhance the capacitive performance of carbon-electrode supercapacitors ( Wei et al, 2022 ). The carbonization of N-containing biomaterials is an effective strategy for the production of N-doped carbon (Feng et al, 2021), and much research has focused on the fabrication of N-doped carbon electrodes from the graphitization of natural silk ( Yang et al, 2021 ; Zhou et al, 2022 ).…”