Black Liquor and Wood Char-Derived Nitrogen-Doped Carbon Materials for Supercapacitors

Abstract

Herein, we present a synthesis route for high-efficiency nitrogen-doped carbon materials using kraft pulping residue, black liquor, and wood charcoal as carbon sources. The synthesized nitrogen-doped carbon materials, based on black liquor and its mixture with wood charcoal, exhibited high specific surface areas (SSAs) of 2481 and 2690 m2 g−1, respectively, as well as a high volume of mesopores with an average size of 2.9–4.6 nm. The nitrogen content was approximately 3–4 at% in the synthesized nitrogen-doped carbon materials. A specific capacitance of approximately 81–142 F g−1 was achieved in a 1 M Na2SO4 aqueous solution at a current density of 0.2 A g−1. In addition, the specific capacitance retention was 99% after 1000 cycles, indicating good electrochemical stability.

Application of modified acetylene carbon black with different particle sizes in sodium-ion batteries

“…The use of carbon material as Nib anode has great potential due to its stable electrochemical properties, low potential and low cost. [4,5] Graphite has been widely used in the commercialization of lithium-ion batteries, but due to the larger radius of sodium atoms than lithium atoms, only a small number of sodium atoms are embedded in graphite, and the storage capacity of sodium ions in graphite is less than 35 mAh/g, so researchers have turned to the study of non-graphite carbon materials Such as hard carbon [6][7][8][9][10] soft carbon etc. [11,12] Although hard carbon has a good application prospect in Nib, its cycling performance and rate ability need to be improved, and hard carbon tends to form a prominent solid electrolyte interface layer (SEI) on a large surface area, resulting in a low initial cycling e ciency (ICE) of Nib.…”

Heteroatom-Doped Carbon Nanomaterials Derived from Black Liquor for Electrochemical Oxygen Reduction Reaction

“…37 Heteroatom-doped nanocarbons from black liquor have mainly been previously studied as electrode materials for supercapacitors and batteries. 4,38,39 There are also a few other findings, for example, Zhao et al have used black liquor to develop a hydrogen peroxide catalyst material in alkaline media. 40 Other reports use non-industrial black liquor or concentrate instead on lignin.…”

“…Additional doping is especially crucial in the case of lignin-based catalysts, as lignin itself naturally lacks nitrogen functionalities, which could finally lead to nitrogen-doped carbon materials . Heteroatom-doped nanocarbons from black liquor have mainly been previously studied as electrode materials for supercapacitors and batteries. ,, There are also a few other findings, for example, Zhao et al have used black liquor to develop a hydrogen peroxide catalyst material in alkaline media . Other reports use non-industrial black liquor or concentrate instead on lignin. , To the best of our knowledge, there are no other articles that use industrial black liquor as a precursor to synthesize active non-noble metal-free electrocatalysts for the four-electron ORR process without additional metal doping.…”