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Lei Liu

Bio: Lei Liu is an academic researcher from Shanghai Jiao Tong University. The author has contributed to research in topics: Coating & Corrosion. The author has an hindex of 20, co-authored 55 publications receiving 1423 citations.


Papers
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Journal ArticleDOI
26 Jan 2015-ACS Nano
TL;DR: This large-scale preparation of sub-3 nm atomic layers Co3O4 nanofilms with a nonsurfactant and substrate-free hydrothermal method highlighted the reconstruction of cobalt-ammonia complexes and synergistic effect of free ammonia and nitrate on film growth control.
Abstract: Two-dimensional materials often show a range of intriguing electronic, catalytic, and optical properties that differ greatly from conventional nanoparticles. Herein, we demonstrate the large-scale preparation of sub-3 nm atomic layers Co3O4 nanofilms with a nonsurfactant and substrate-free hydrothermal method. This successful preparation of ultrathin nanofilms highlighted the reconstruction of cobalt-ammonia complexes and synergistic effect of free ammonia and nitrate on film growth control. Subsequent performance tests uncovered that these sub-3 nm atomic layer Co3O4 nanofilms exhibited an ultrahigh specific capacitance of 1400 F/g in the first galvanostatic charge/discharge test. The specific capacitance of Co3O4 nanofilms only slightly decayed less than 3% after 1500 cycling tests. With some parameter adjustments, similar Co(OH)2 nanofilms with a thickness of 3.70 ± 0.10 nm were also prepared. The Co(OH)2 nanofilms possessed maximum specific capacitance of 1076 F/g and peak performance attenuation of about 2% after a cycle stability test.

231 citations

Journal ArticleDOI
TL;DR: A review of diffusion coating on magnesium alloys can be found in this article, where the basic principles and challenges of fabricating diffusion coatings on magnesium alloy are discussed, and the corrosion and mechanical properties of the coatings are also discussed on the basis of literature data.

136 citations

Journal ArticleDOI
Lei Liu1, Weiwei Li1, Yiping Tang1, Bin Shen1, Wenbin Hu1 
25 Mar 2009-Wear
TL;DR: In this paper, the friction and wear properties of short carbon fibers (SCFs) reinforced aluminum matrix composite were studied and the influences of the fiber volume fraction, load applied, rotating speed, and wear mechanism were discussed.

97 citations

Journal ArticleDOI
TL;DR: In this article, the shape evolution of palladium cuboctahedrons was studied and the shape-dependent catalytic performances of as-obtained palladium nanocrystals were analyzed.
Abstract: This paper reports a convenient and facile preparation of single-crystalline palladium with controllable shape based on the reduction of kinetic control via hydrochloric acid oxidative etching. The concentration of HCl added to the reaction solution was found to be crucial for the shape evolution of palladium nanocrystals from nanocubes bounded by {100} facets to octahedrons by {111} facets. Palladium nanocubes can be readily obtained at a fast reduction rate without the involvement of additional HCl. With the introduction of a certain amount of HCl to the precursor solution, truncated nanocubes with {111} facets were formed, and the increase of HCl led to the slower reduction rate and the formation of palladium cuboctahedrons enclosed by six {100} facets and eight {111} facets at the expense of gradual shrinkage of {100} facets. The probable mechanism of morphological transformation was proposed upon a batch of experiments. The shape-dependent catalytic performances of as-obtained palladium nanocrystals ...

83 citations

Journal ArticleDOI
Yiping Tang1, Lei Liu1, Weiwei Li1, Bin Shen1, Wenbin Hu1 
TL;DR: In this article, three kinds of coatings, Ni, Cu and Al2O3, were obtained on the surface of short carbon fibers (SCFs), and the interface characteristics and mechanical properties of SCFs/Al composites with the various coatings were systematically studied.

82 citations


Cited by
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Journal ArticleDOI

[...]

08 Dec 2001-BMJ
TL;DR: There is, I think, something ethereal about i —the square root of minus one, which seems an odd beast at that time—an intruder hovering on the edge of reality.
Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

33,785 citations

Journal ArticleDOI
TL;DR: The principles and methods of designing and optimizing electrolytes for ES performance and application are highlighted through a comprehensive analysis of the literature, and challenges in producing high-performing electrolytes are analyzed.
Abstract: Electrolytes have been identified as some of the most influential components in the performance of electrochemical supercapacitors (ESs), which include: electrical double-layer capacitors, pseudocapacitors and hybrid supercapacitors. This paper reviews recent progress in the research and development of ES electrolytes. The electrolytes are classified into several categories, including: aqueous, organic, ionic liquids, solid-state or quasi-solid-state, as well as redox-active electrolytes. Effects of electrolyte properties on ES performance are discussed in detail. The principles and methods of designing and optimizing electrolytes for ES performance and application are highlighted through a comprehensive analysis of the literature. Interaction among the electrolytes, electro-active materials and inactive components (current collectors, binders, and separators) is discussed. The challenges in producing high-performing electrolytes are analyzed. Several possible research directions to overcome these challenges are proposed for future efforts, with the main aim of improving ESs' energy density without sacrificing existing advantages (e.g., a high power density and a long cycle-life) (507 references).

2,480 citations

Journal ArticleDOI
24 Dec 2004-Science

1,949 citations

Journal ArticleDOI
TL;DR: In this article, the authors focus on the recent development in the synthesis, property characterization and application of aluminum, magnesium, and transition metal-based composites reinforced with carbon nanotubes and graphene nanosheets.
Abstract: One-dimensional carbon nanotubes and two-dimensional graphene nanosheets with unique electrical, mechanical and thermal properties are attractive reinforcements for fabricating light weight, high strength and high performance metal-matrix composites. Rapid advances of nanotechnology in recent years enable the development of advanced metal matrix nanocomposites for structural engineering and functional device applications. This review focuses on the recent development in the synthesis, property characterization and application of aluminum, magnesium, and transition metal-based composites reinforced with carbon nanotubes and graphene nanosheets. These include processing strategies of carbonaceous nanomaterials and their composites, mechanical and tribological responses, corrosion, electrical and thermal properties as well as hydrogen storage and electrocatalytic behaviors. The effects of nanomaterial dispersion in the metal matrix and the formation of interfacial precipitates on these properties are also addressed. Particular attention is paid to the fundamentals and the structure–property relationships of such novel nanocomposites.

877 citations

Journal ArticleDOI
09 Oct 2019
TL;DR: In this article, the current state of understanding of the electrode-electrolyte interaction in supercapacitors and battery-supercapacitor hybrid devices is reviewed, and factors that affect the overall performance of the devices such as the ionic conductivity, mobility, diffusion coefficient, radius of bare and hydrated spheres, ion solvation, viscosity, dielectric constant, electrochemical stability, thermal stability and dispersion interaction.
Abstract: Electrolytes are one of the vital constituents of electrochemical energy storage devices and their physical and chemical properties play an important role in these devices' performance, including capacity, power density, rate performance, cyclability and safety. This article reviews the current state of understanding of the electrode–electrolyte interaction in supercapacitors and battery–supercapacitor hybrid devices. The article discusses factors that affect the overall performance of the devices such as the ionic conductivity, mobility, diffusion coefficient, radius of bare and hydrated spheres, ion solvation, viscosity, dielectric constant, electrochemical stability, thermal stability and dispersion interaction. The requirements needed to design better electrolytes and the challenges that still need to be addressed for building better supercapacitive devices for the competitive energy storage market have also been highlighted.

549 citations