Electrochemical synthesis of phosphorus-doped graphene quantum dots for free radical scavenging

Abstract

In this work, phosphorus-doped graphene quantum dots (P-GQDs) with a high phosphorus doping content (>7 at%) are synthesized via an electrochemical approach. Sodium phytate (CHNaOP), a green food antioxidant additive, is used as the electrolyte for providing both a phosphorus source and an electrolysis environment. The obtained P-GQDs exhibit excellent scavenging activity of free radicals, such as hydroxyl radicals (˙OH) and 2,2-diphenyl-1-picrylhydrazyl (DPPH). Combined with Raman, FT-IR, and XPS spectral analyses, the reason for high phosphorus content and the mechanism of free radical scavenging of P-GQDs are investigated in our work.

Designing Highly Efficient and Long‐Term Durable Electrocatalyst for Oxygen Evolution by Coupling B and P into Amorphous Porous NiFe‐Based Material

“…The P 2p3/2 peaks at 132.70 eV are assigned to phosphates. The XPS spectrum of the O 1s in Figure e finds intense peaks at ≈530 and ≈531 eV that correspond to high surface contents of MO bonds in metal oxides and MOH bonds in metal hydroxides, respectively, which are in good agreement with the TEM observations of an oxidative shell on the a‐NiFePB surface. The formation of the a‐NiFePB phase is further characterized by X‐ray absorption spectroscopy (XAS).…”

A Library of Doped-Graphene Images via Transmission Electron Microscopy

“…Considering the GQDs' small size, favorable hydrophilicity and biocompatibility, the novel scavenging ability of free radicals widen their application potential to organisms or biotechnology and medicine related fields. In 2016, a new technique for synthesizing P-doped graphene quantum dots (P-GQDs) with high phosphorus doping concentration was reported by Li et al (Figure 15a-c) [77]. The obtained P-GQDs showed an excellent ability to scavenge free radicals and an outstanding anti-erosion performance and opened up applications in the biomedical and polymeric materials.…”

“…These include (I) gas sensor by B dopant [25], transistor by B dopant [94], N dopant [40,41], NO2 dopant [69]; (II) biosensor by N dopant [86]; (III) solar cell by HNO3 dopant [51,52], SoCl2 dopant [50,51], B dopant [26], HCl dopant [51], H2O2 dopant [51]; (IV) fuel cell by B dopant [27], N dopant [38,96]; (V) Li-ion battery by SnO2/N codopant [35], MoS2/N co-dopant [36], O2 dopant [84]; (VI) supercapacitor by N dopant [39]; (VII) FET by N dopant [44,88], diazonium salt and PEI dopants [74], NH3 dopant [73], N2H4 dopant [61,62], oMeO-DMBI dopant [63]; (VIII) photovoltaic cells by AuCl3 dopant [29]; electrocatalyst for ORR by S/N co-dopant [34], FeN4 dopant [32], N dopant [37,89], P dopant [79,80], N2/P co-dopant [76]; (IX) PLED by TFSA dopant [48]; (X) Free-radical scavenging by P dopant [77]; and (XI) energy storage and conversion by S dopant [33]. In general, the doped-graphene exhibited the diverse potentials with physical and chemical characteristics in further improvement the unexploited and unexplored potential in graphene.…”

“…This structure favors electrocatalysis applications because the active sites can be exposed to reactant molecules and the incorporated graphene nanosheets beneath the N-P co-doped carbon can facilitate electron transportation during the redox process and improve the electrocatalytic activity and electrochemical kinetic energy [76]. In 2016, a new technique for synthesizing P-doped graphene quantum dots (P-GQDs) with high phosphorus doping concentration was reported by Li et al (Figure 15a-c) [77]. The obtained P-GQDs showed an excellent ability to scavenge free radicals and an outstanding anti-erosion performance and opened up applications in the biomedical and polymeric materials.…”

“…Substitutional doping with B, phosphorus (P), N, or sulfur (S) single atoms in the carbon network could modulate the chemical characteristics, create new active sites, and greatly improve the catalytic activity of graphene [27,33,37,43,[77][78][79][80]. In particular, co-doping through the mixture of two or three metal elements with electronegativity could produce a novel electron distribution resulted in a synergistic effect [86].…”