Multiple doping of graphene oxide foams and quantum dots: new switchable systems for oxygen reduction and water remediation

Abstract

ARTICLE This journal isSingle-and multi-Boron, Nitrogen, Sulphur doped graphene oxide quantum dots and threedimensional foams are synthesized by a simple and environmental friendly electrochemical method. The electrochemical activity of these materials in the oxygen reduction reaction is investigated by cyclic voltammetry and rotating disk electrode measurements. The experimental data demonstrate that the reaction selectivity is controlled by the oxidation degree of the materials: as-prepared graphene oxide quantum dots, which present highly oxidized functional groups, follow a two-electron reduction pathway and produce hydrogen peroxide, whereas after a reduction treatment by NaBH 4 , the same materials favour a fourelectron reduction of oxygen to water. The high selectivity and high efficiency of the graphene oxide quantum dots for the production of hydrogen peroxide can be efficiently used for water remediation applications (phenol decomposition). ARTICLEThis journal is

A Nanopore-Structured Nitrogen-Doped Biocarbon Electrocatalyst for Oxygen Reduction from Two-Step Carbonization of Lemna minor Biomass

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Nitrogen and Sulfur Doped Mesoporous Carbons, Prepared from Templating Silica, as Interesting Material for Supercapacitors

“…Another important aspect is the presence of functional groups on the surface of carbon materials, which induces pseudo‐faradaic processes, leading to a substantial increase in the total capacitance. Functional groups of nitrogen, boron, phosphorus and sulfur are commonly pinned onto the carbon surface according to a post functionalization procedure (ion implantation, radical reaction, grafting, etc.) or by employing a suitable precursor during the pyrolysis process ,…”

Using aminopyrine as a nitrogen-enriched small molecule precursor to synthesize high-performing nitrogen doped mesoporous carbon for catalyzing oxygen reduction reaction

“…This result is consistent with the description in literature. 22,26,27,44 As we have described above, the nal Fe content of AP/SiO 2 catalyst is around 0.4 wt%. According to literature, even a slight trace of metallic impurities in carbon materials may have a strong inuence on the ORR.…”