Facile one-pot synthesis and application of nitrogen and sulfur-doped activated graphene in simultaneous electrochemical determination of hydroquinone and catechol

Abstract

Nitrogen (N) and sulfur (S) co-doped activated graphene (N,S-AGR) was prepared by the one-pot pyrolysis of a mixture of graphene oxide (GO), thiourea, and potassium hydroxide (KOH), where thiourea acts as the source of N and S dopants and KOH is the activator for porosity. N,S-AGR with a dopant abundance of 2.8 at% N and 2.3 at% S was then used as a high-activity electrocatalyst in the fabrication of an electrochemical sensor for simultaneous determination of dihydroxybenzene isomers, hydroquinone (HQ) and catechol (CC), in aqueous solution. Compared with the bare glassy carbon electrode (GCE), the electrodes modified with N,S-AGR showed enhanced electrochemical performance toward HQ and CC in both cyclic voltammetric (CV) and differential pulse voltammetric (DPV) measurements because of their enlarged surface area, enhanced electron-transfer rate and increased active sites. Compared with some recently reported electrochemical sensors based on graphene composites, the N,S-AGR modified electrode exhibits higher sensitivity, a much lower detection limit and a comparable linear range for the simultaneous determination of HQ and CC. Moreover, the proposed sensor is promising in practical application for the satisfactory recoveries obtained in real water sample analyses.

Pd embedded N, S co‐doped graphene wrapped core‐shell magnetic nanospheres: Engineered stable nanocatalyst for Suzuki couplings

“…The C 1 s peak could be deconvoluted into four peaks (Figure a), corresponds to C − C/C=C (284.5 eV), C − S (284.9 eV), C − N/C=O (286.1 eV), and C=O (288.5 eV) . The N 1 s peak could also be resolved into four peaks associated with pyridinic‐N, pyrrolic‐N, graphitic‐N and oxidized pyridinic‐N (Figure b) . The S 2p peak indicated the existence of three types of S species.…”

Electrochemical Sensing Platforms of Dihydroxybenzene: Part 1 – Carbon Nanotubes, Graphene, and their Derivatives

“…GR suffers from aggregation through π–π stacking, which reduces its electrochemical activity. Xiao et al [153] . incorporated heteroatom co‐doping on activated GR (AGR) to prepare N‐ and S‐co‐doped AGR (Figure 14).…”

“… a,b) SEM images of N,S‐GR, c,d) AGR, and e,f) N,S‐AGR. Reproduced with permission [153] . Copyright 2016, Royal Society of Chemistry.…”

Modulating Metal‐Free and Non‐Enzymatic Electrocatalytic Activity of sp2 Carbons Towards H2O2 Reduction by a Facile and Low‐Temperature Electrochemical Approach

“…The nitrogen doped/incorporated carbon surfaces were used as metal‐free electrocatalysts towards ORR, OER, HER and H 2 O 2 reduction and are of great importance in energy and sensor applications . The nitrogen doped/incorporated carbon materials were developed by different methods which include hydrothermal methods, pyrolysis, chemical vapor deposition and plasma treatment etc ,. All these strategies have their own limitations such as high temperature and complicated instruments requirement, and high cost.…”

“…Graphene‐based catalysts are getting increasing importance because of their unique properties such as a thin layer of sp 2 carbon network, high surface area, high conductivity, high electron mobility and ability to tune its properties by functionalization . The nitrogen doped/incorporated carbon surfaces were used as metal‐free electrocatalysts towards ORR, OER, HER and H 2 O 2 reduction and are of great importance in energy and sensor applications . The nitrogen doped/incorporated carbon materials were developed by different methods which include hydrothermal methods, pyrolysis, chemical vapor deposition and plasma treatment etc ,.…”