Synthesis, composition and spin-dynamics of FCC and HCP phases of pyrolysis derived Co-nanoparticles embedded in amorphous carbon matrix

Hospital-acquired infections are responsible for a significant part of morbidity and mortality. Among the possible modes of transmission, this study focuses on environmental surfaces by developing innovative antibacterial coatings that can be applied on interior fittings in hospitals. This work aims to optimize a coating made of an amorphous carbon matrix doped with silver (a-C:H:Ag) produced by a hybrid PVD/PECVD process and to evaluate its antibacterial activity. We present a coating characterization (chemical composition and morphology) as well as its stability in an ageing process and after multiple exposures to bacteria. The antibacterial activity of the coatings is demonstrated against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) bacteria through several bioassays. Moreover, the data suggest a crucial role of silver diffusion towards the surface and nanoparticle formation to explain the very promising anti-bacterial activities reported in this work.

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Microwave Absorption of Crystalline Fe/MnO@C Nanocapsules Embedded in Amorphous Carbon

Nano-Micro Letters ◽

10.1007/s40820-020-0388-4 ◽

2020 ◽

Vol 12 (1) ◽

Cited By ~ 18

Author(s):

Gaihua He ◽

Yuping Duan ◽

Huifang Pang

Keyword(s):

Dielectric Loss ◽

Amorphous Carbon ◽

High Performance ◽

Magnetic Loss ◽

Synthesis Method ◽

Domain Size ◽

Carbon Matrix ◽

Effective Bandwidth ◽

General Duty ◽

Enhanced Absorption

AbstractCrystalline Fe/MnO@C core–shell nanocapsules inlaid in porous amorphous carbon matrix (FMCA) was synthesized successfully with a novel confinement strategy. The heterogeneous Fe/MnO nanocrystals are with approximate single-domain size which gives rise to natural resonance in 2–18 GHz. The addition of MnO2 confines degree of graphitization catalyzed by iron and contributes to the formation of amorphous carbon. The heterogeneous materials composed of crystalline–amorphous structures disperse evenly and its density is significantly reduced on account of porous properties. Meanwhile, adjustable dielectric loss is achieved by interrupting Fe core aggregation and stacking graphene conductive network. The dielectric loss synergistically with magnetic loss endows the FMCA enhanced absorption. The optimal reflection loss (RL) is up to − 45 dB, and the effective bandwidth (RL < − 10 dB) is 5.0 GHz with 2.0 mm thickness. The proposed confinement strategy not only lays the foundation for designing high-performance microwave absorber, but also offers a general duty synthesis method for heterogeneous crystalline–amorphous composites with tunable composition in other fields.

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Fe2C Nanocrystals Encapsulated in an Active Amorphous Carbon Matrix As High Performance Electrodes for Lithium-Ion Batteries

ECS Meeting Abstracts ◽

10.1149/ma2017-01/5/466 ◽

2017 ◽

Keyword(s):

Lithium Ion Batteries ◽

Amorphous Carbon ◽

High Performance ◽

Lithium Ion ◽

Carbon Matrix

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Photocatalytic and ferromagnetic properties of electrically conducting multifunctional Ni/NiO nanocomposites in amorphous carbon matrix

Materials Science and Engineering B ◽

10.1016/j.mseb.2017.11.017 ◽

2018 ◽

Vol 228 ◽

pp. 132-141 ◽

Cited By ~ 20

Author(s):

V. Ganeshchandra Prabhu ◽

Abdul Rasheed Paloly ◽

N.G. Divya ◽

M. Junaid Bushiri

Keyword(s):

Amorphous Carbon ◽

Carbon Matrix ◽

Ferromagnetic Properties ◽

Electrically Conducting

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Characterization and Tribological Properties of Nanostructured Copper/Carbon Composite Films Prepared by Microwave Plasma-Assisted Dual Deposition Processes

MRS Proceedings ◽

10.1557/proc-750-y2.4 ◽

2002 ◽

Vol 750 ◽

Author(s):

François Thiery ◽

Yves Pauleau ◽

Jacques Pelletier

Keyword(s):

Amorphous Carbon ◽

Electron Cyclotron Resonance ◽

Microwave Plasma ◽

Plasma Reactor ◽

Composite Films ◽

Chemical Vapor ◽

Carbon Matrix ◽

Carbon Composite ◽

Carbon Films ◽

Radius Of Curvature

ABSTRACTNanocrystalline copper/hydrogenated amorphous carbon films have been deposited on Si substrates at the floating potential using a distributed electron cyclotron resonance microwave plasma reactor. In this deposition technique, the microwave plasma-enhanced chemical vapor deposition process of carbon from argon-methane or argon-acetylene mixtures of various compositions was associated with the sputter deposition of copper from a copper target. The total pressure was fixed at 0.13 Pa. For deposition, the substrates mounted on a water-cooled substrate holder were maintained at ambient temperature. The composition of films determined by Rutherford backscattering spectroscopy, energy recoil detection analyses and nuclear reaction analyses was investigated as a function of the gas phase composition. The structure of films was identified by X-ray diffraction (XRD) techniques and the size of copper crystallites incorporated in the amorphous carbon matrix was deduced from XRD data. The magnitude of residual stresses developed in these films was calculated from the radius of curvature of film/substrate samples determined by profilometry. The residual stress values were found to be nearly independent on the composition of films and deposition parameters.

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