Biomass-Derived Activated Carbon Sheets with Tunable Oxygen Functional Groups and Pore Volume for High-Performance Oxygen Reduction and Zn–Air Batteries

Abstract

Biomass-derived activated carbon has attracted much attention in electrochemical energy systems, and its great potential can be further unlocked for achieving high-performance by tuning its composition and structure. Herein, we prepared activated carbon using wheat straw as the biomass feedstock. The oxygen functional groups and pore volume of the target activated carbon were successfully tuned using the mixed activator of potassium carbonate and potassium hydroxide. As a result, the activated carbon (named as AC-HC) displayed an excellent oxygen reduction reaction (ORR) behavior in terms of a small half-wave potential of 0.77 V and a large limiting current density, resulting in Zn−air batteries with a high trip efficiency of 60.7% and a long cycle life (280 h/1680 cycles).

Trapa natans Husk‐Derived Nanoporous Carbons as Electrode Materials for Sustainable High‐Power Microbial Fuel Cell Supercapacitor Systems

“…The mesoporous structure acts as a highway to facilitate the reactions at the catalytic sites, thus improving the ORR performance. [70] All the samples in Figure 3e show similar XRD patterns with the (002) and (100) characteristic peaks of activated carbon. [71] The broad peaks are not obvious, which indicates that the TNHs are amorphous carbon because of their porous structure.…”

“…The mesoporous structure acts as a highway to facilitate the reactions at the catalytic sites, thus improving the ORR performance. [ 70 ]…”

Coupling behavior and enhancement mechanism of porous structure, graphite microcrystals, and oxygen-containing groups of activated biochar for the adsorption of phenol

“…Amorphous structural defects may originate from the defective carbon matrix created by the hierarchical micro/mesoporous formation or oxygen-containing groups. 41 It was obvious that H 3 PO 4 -ABs possessed the highest I D / I G values, between 0.96 and 1.13, implying a relatively low degree of graphitization.…”

Surface oxidation of commercial activated carbon with enriching carboxyl groups for high-yield electrocatalytic H2O2 production

“…However, commercially chemical activation (e.g. phosphoric acid) technology results in the carbon materials with poor porosity, nonabundant atomic doping and/or even large particles of ash impurities to further block the electrocatalytic applications [20]. Therefore, exploring a purification and surface functionalization process to effectively regulate the composition/structure and performance of electrocatalytic H 2 O 2 production is a significant and urgent task.…”