Publications by authors named "Guangyu Lei"

6 Publications

  • Page 1 of 1

Nitrogen-carbon materials base on pyrolytic graphene hydrogel for oxygen reduction.

J Colloid Interface Sci 2021 Jun 8;602:274-281. Epub 2021 Jun 8.

Lab of Advanced Nano-structures & Transfer Processes, Department of Chemical Engineering, Tianjin University, Tianjin 300354, China; Chemistry and Chemical Engineering Guangdong Laboratory, Shantou 515031 China. Electronic address:

Hypothesis: Oxygen reduction reaction (ORR) has played a significant role in the utilization of energy nowadays. Nitrogen-doped carbon materials are seen as promising catalysts for ORR, so it is of great significance in studying the functions of different nitrogen moieties.

Experiments: The graphene hydrogel-based nitrogen-arbon materials (GH N-C) were fabricated by first obtaining a gel through hydrothermal treatment using graphene oxide (GO) as precursor, and then calcined in an ammonia atmosphere at different temperatures to form N-doped graphitized materials with divers nitrogen configuration.

Findings: GH N-C materials with tunable nitrogen configuration were synthesized by a two-step method base on graphene hydrogel. Benefiting from the 3D hydrogel structure, rich defects and optimized chemical properties, GH N-C-900 prepared by NH pyrolysis at 900 °C exhibits an excellent electrocatalytic performance toward ORR, with the onset potential of 0.947 ± 0.013 V versus RHE, half-wave potential of 0.830 ± 0.010 V versus RHE, electron transfer number of 3.61-3.99, along as methanol tolerance and superior long-term stability. Comprehensive studies have shown that there is a positive correlation between the total amount of pyrrolic-N and quaternary-N and the catalytic performance of ORR.
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http://dx.doi.org/10.1016/j.jcis.2021.06.036DOI Listing
June 2021

Bimetallic ZIF-Derived Co/N-Codoped Porous Carbon Supported Ruthenium Catalysts for Highly Efficient Hydrogen Evolution Reaction.

Nanomaterials (Basel) 2021 May 6;11(5). Epub 2021 May 6.

Lab of Advanced Nano-Structure and Transfer Process, Department of Chemical Engineering, Tianjin University, Tianjin 300354, China.

Exploring the economical, powerful, and durable electrocatalysts for hydrogen evolution reaction (HER) is highly required for practical application. Herein, nanoclusters-decorated ruthenium, cobalt nanoparticles, and nitrogen codoped porous carbon ([email protected]) are prepared with bimetallic zeolite imidazole frameworks (ZnCo-ZIF) as the precursor. Thus, the prepared [email protected] catalyst with a low Ru loading of 3.13 wt% exhibits impressive HER catalytic behavior in 1 M KOH, with an overpotential of only 30 mV at the current density of 10 mA cm, Tafel slope as low as 32.1 mV dec, and superior stability for long-time running with a commercial 20 wt% Pt/C. The excellent electrocatalytic properties are primarily by virtue of the highly specific surface area and porosity of carbon support, uniformly dispersed Ru active species, and rapid reaction kinetics of the interaction between Ru and O.
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http://dx.doi.org/10.3390/nano11051228DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8148513PMC
May 2021

Bifunctional Graphene-Based Metal-Free Catalysts for Oxidative Coupling of Amines.

ACS Appl Mater Interfaces 2019 Sep 20;11(35):31844-31850. Epub 2019 Aug 20.

Lab of Advanced Nano Structures & Transfer Processes, Department of Chemical Engineering , Tianjin University , Tianjin 300354 , P. R. China.

Graphene oxide (GO), an emerging material ornamented with oxygen-containing functional groups, is becoming a promising alternative for various applications. The piranha solution treatment of GO can increase oxygen-containing functional groups and result in improved graphene oxide (IGO), as well as restore the functional groups lost because of the reaction. It is found that GO can oxidize the amine to the corresponding imine in the absence of oxygen and a catalyst, and the obtained IGO even shows higher activity. In addition, the piranha solution can partially restore the reactivity of GO after the reaction. The different roles of oxygen-containing functional groups in the oxidative coupling reaction are investigated. A possible reaction mechanism for the oxidation of benzylamine to -benzylidene benzylamine is also proposed.
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http://dx.doi.org/10.1021/acsami.9b08741DOI Listing
September 2019

Magnetic Au-Ag-γ-Fe₂O₃/rGO Nanocomposites as an Efficient Catalyst for the Reduction of 4-Nitrophenol.

Nanomaterials (Basel) 2018 Oct 25;8(11). Epub 2018 Oct 25.

Lab of Advanced Nano-structures & Transfer Processes, Department of Chemical Engineering, Tianjin University, Tianjin 300354, China.

In this paper, a facile route has been developed to prepare magnetic trimetallic Au-Ag-γ-Fe₂O₃/rGO nanocomposites. The impact of the preparation method (the intensity of reductant) on the catalytic performance was investigated. The nanocomposites were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The prepared nanocomposites show fine catalytic activity towards the reduction reaction of 4-nitrophenol (4-NP). The nanocomposites also have superparamagnetism at room temperature, which can be easily separated from the reaction systems by applying an external magnetic field.
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http://dx.doi.org/10.3390/nano8110877DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6266811PMC
October 2018

Polyaniline Derived N-Doped Carbon-Coated Cobalt Phosphide Nanoparticles Deposited on N-Doped Graphene as an Efficient Electrocatalyst for Hydrogen Evolution Reaction.

Small 2018 01 17;14(2). Epub 2017 Nov 17.

Lab of Advanced Nano Structures & Transfer Processes, Department of Chemical Engineering, Tianjin University, Tianjin, 300354, P. R. China.

The development of highly efficient and durable non-noble metal electrocatalysts for the hydrogen evolution reaction (HER) is significant for clean and renewable energy research. This work reports the synthesis of N-doped graphene nanosheets supported N-doped carbon coated cobalt phosphide (CoP) nanoparticles via a pyrolysis and a subsequent phosphating process by using polyaniline. The obtained electrocatalyst exhibits excellent electrochemical activity for HER with a small overpotential of -135 mV at 10 mA cm and a low Tafel slope of 59.3 mV dec in 0.5 m H SO . Additionally, the encapsulation of N-doped carbon shell prevents CoP nanoparticles from corrosion, exhibiting good stability after 14 h operation. Moreover, the as-prepared electrocatalyst also shows outstanding activity and stability in basic and neutral electrolytes.
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http://dx.doi.org/10.1002/smll.201702895DOI Listing
January 2018

Approach to osteomyelitis treatment with antibiotic loaded PMMA.

Microb Pathog 2017 Jan 26;102:42-44. Epub 2016 Nov 26.

Department of Orthopedics, Hong Hui Hospital, Xi'an Jiaotong University College of Medicine, Shaanxi 710054, China.

Background: To reduce the incidence of osteomyelitis infection, local antibiotic impregnated delivery systems are commonly used as a promising and effective approach to deliver high antibiotic concentrations at the infection site.

Objective: The objective of this review was to provide a literature review regarding approach to osteomyelitis treatment with antibiotic loaded PMMA.

Study Design: Literature study regarding osteomyelitis treatment with antibiotic loaded carriers using key terms Antibiotic, osteomyelitis, biodegradable PMMA through published articles. Hands searching of bibliographies of identified articles were also undertaken.

Conclusion: We concluded that Antibiotic-impregnated PMMA beads are useful options for the treatment of osteomyelitis for prolonged drug therapy.
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http://dx.doi.org/10.1016/j.micpath.2016.11.016DOI Listing
January 2017
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