MnO 2 / Co 3 O 4 with N and S co‐doped graphene oxide bimetallic nanocomposite for hybrid supercapacitor and photosensor applications

Highly bright-fluorescent N (nitrogen), S (sulfur) co-doped graphene quantum dots (GQDs) were synthesized through an modified hydrothermal method. The doped GQDs are smaller than 10 nm in size in average and stable in aqueous solution. Unlike many reports on graphene oxide (GO), the as-synthesized doped GQDs exhibit bright blue photoluminescence (PL) emission and the emission wavelength is excitation-independent. The intriguling results indicate that GQDs may have great potential in the optic and optoelectronic applications.

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Electroluminescence and Photocatalytic Hydrogen Evolution of S,N Co-doped Graphene Oxide Quantum Dots

Journal of Materials Chemistry A ◽

10.1039/d1ta09917e ◽

2022 ◽

Author(s):

Tung-Kung Wu ◽

Tzu-Yang Cheng ◽

Feng-Pai Chou ◽

Sheng-Cih Huang ◽

Chin-Yuan Chang

Keyword(s):

Quantum Dots ◽

Graphene Oxide ◽

Hydrogen Evolution ◽

High Yield ◽

Hydrothermal Route ◽

Photocatalytic Hydrogen Evolution ◽

Facile Hydrothermal Route ◽

Doped Graphene ◽

Graphene Oxide Quantum Dots ◽

Co Doped

A facile hydrothermal route to synthesize S,N co-doped graphene oxide quantum dots (S,N-GOQDs) with stable electroluminescence, photoluminescence, and photocatalytic properties was demonstrated. The synthesized S,N-GOQDs show high yield and excitation–independent...

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Long-term corrosion protection of styrene acrylic coatings enhanced by fluorine and nitrogen co-doped graphene oxide

Nanotechnology ◽

10.1088/1361-6528/ac3d65 ◽

2021 ◽

Author(s):

Haoran An ◽

Yanan Gao ◽

Shengyuan Wang ◽

Shuang Liang ◽

Xin Wang ◽

...

Keyword(s):

Graphene Oxide ◽

Corrosion Protection ◽

Electrochemical Impedance ◽

Hydrothermal Process ◽

Polymer Coatings ◽

Resin Matrix ◽

Physical Barrier ◽

Doped Graphene ◽

Acrylic Coatings ◽

Co Doped

Abstract Graphene materials are widely used as a physical barrier when applying anticorrosion polymer coatings due to their large surface area and layered structure. However, the electrical conductivity of intrinsic graphene can accelerate galvanic corrosion and shorten the protection period. In this work, fluorine and nitrogen co-doped graphene oxide (FNGO) was synthesized by a hydrothermal process and acted as an anticorrosion filler in waterborne styrene acrylic coatings. Styrene acrylic coatings with 0.4 wt% FNGO showed a corrosion current density that was two orders of magnitude lower than the other samples in the potential polarization test and the largest impedance modulus in the electrochemical impedance spectroscopy (EIS) results. The outstanding corrosion protection was attributed to the graphene acting as a physical barrier and the synergistic effect of the doped fluorine and nitrogen. In addition to the “labyrinth effect” of the graphene matrix, the nitrogen atoms inserted in the graphene plane and fluorine atoms grafted on the graphene simultaneously adjusted the electrical properties of graphene, prohibiting electron transport between it and the styrene acrylic resin matrix. This result indicates that doped graphene oxide has great potential to increase the corrosion resistance of waterborne coatings.

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