Electrochemical capacitors, which can store large amount of electrical energy with the capacitance of thousands of Farads, have recently been attracting enormous interest and attention. Carbon nanostructures such as c...Electrochemical capacitors, which can store large amount of electrical energy with the capacitance of thousands of Farads, have recently been attracting enormous interest and attention. Carbon nanostructures such as carbon nanotubes and graphene are considered as the potentially revolutionary energy storage materials due to their excellent properties. This paper is focused on the application of carbon nanostructures in electrochemical capacitors, giving an overview regarding the basic mechanism, design, fabrication and achievement of latest research progresses for electrochemical capacitors based on carbon nanotubes, graphene and their composites. Their current challenges and future prospects are also discussed.展开更多
Two Minkowski functionals were tested in the capacity of morphological descriptors to quantitatively compare the arrays of vertically-aligned graphene flakes grown on smooth and nanoporous alumina and silica surfaces....Two Minkowski functionals were tested in the capacity of morphological descriptors to quantitatively compare the arrays of vertically-aligned graphene flakes grown on smooth and nanoporous alumina and silica surfaces. Specifically, the Euler-Poincaré characteristic and fractal dimension graphs were used to characterize the degree of connectivity and order in the systems, i.e. in the graphene flake patterns of petal-like and tree-like morphologies on solid substrates, and meshlike patterns (networks) grown on nanoporous alumina treated in low-temperature inductivelycoupled plasma. It was found that the Minkowski functionals return higher connectivity and fractal dimension numbers for the graphene flakepatterns with more complex morphologies, and indeed can be used as morphological descriptors to differentiate among various configurations of vertically-aligned graphene flakes grown on surfaces.展开更多
The results of systematic numerical studies of graphene flakes growth in low-temperature arc discharge plasmas are presented. Diffusion-based growth model was developed, verified using the previously published experim...The results of systematic numerical studies of graphene flakes growth in low-temperature arc discharge plasmas are presented. Diffusion-based growth model was developed, verified using the previously published experiments, and used to investigate the principal effects of the process parameters such as plasma density, electron temperature, surface temperature and time of growth on the size and structure of the plasma-grown graphene flakes. It was demonstrated that the higher growth temperatures result in larger graphene flakes reaching 5 μm, and simultaneously, lead to much lower density of the carbon atoms adsorbed on the flake surface. The low density of the carbon adatoms reduces the probability of the additional graphene layer nucleation on surface of growing flake, thus eventually resulting in the synthesis of the most valuable single-layered graphenes.展开更多
Graphene platelet networks (GPNs) were deposited onto silicon substrates by means of anodic arc discharge ignited between two graphite electrodes.Substrate temperature and pressure of helium atmosphere were optimized ...Graphene platelet networks (GPNs) were deposited onto silicon substrates by means of anodic arc discharge ignited between two graphite electrodes.Substrate temperature and pressure of helium atmosphere were optimized for the production of the carbon nanomaterials.The samples were modified or destroyed with different methods to mimic typical environments responsible of severe surface degradation.The emulated conditions were performed by four surface treatments,namely thermal oxidation,substrate overheating,exposition to glow discharge,and metal coating due to arc plasma.In the next step,the samples were regenerated on the same substrates with identical deposition technique.Damaging and re-growth of GPN samples were systematically characterized by scanning electron microscopy and Raman spectroscopy.The full regeneration of the structural and morphological properties of the samples has proven that this healing method by arc plasma is adequate for restoring the functionality of2D nanostructures exposed to harsh environments.展开更多
Cold atmospheric plasmas are currently gaining increasing attention for cancer therapy.However,very limited studies regarding the interaction mechanisms between plasma species and tissues are available.We report the i...Cold atmospheric plasmas are currently gaining increasing attention for cancer therapy.However,very limited studies regarding the interaction mechanisms between plasma species and tissues are available.We report the interaction of plasma produced species(^(*)OH and HO_(2)^(*))with gap junction by employing reactive molecular dynamics simulations.Our results indicate ^(*)OH and HO_(2)^(*) radicals can chemically react with N-terminal of gap junction resulting in its structural damage.There are two breaking mechanisms being identified:C-N peptide bonds and C-C bonds can be damaged by ^(*)OH and HO_(2)^(*) radicals,respectively.Our findings could be particularly important for understanding the plasma-generated reactive species triggering bystander effect based on gap junction intercellular communication.展开更多
文摘Electrochemical capacitors, which can store large amount of electrical energy with the capacitance of thousands of Farads, have recently been attracting enormous interest and attention. Carbon nanostructures such as carbon nanotubes and graphene are considered as the potentially revolutionary energy storage materials due to their excellent properties. This paper is focused on the application of carbon nanostructures in electrochemical capacitors, giving an overview regarding the basic mechanism, design, fabrication and achievement of latest research progresses for electrochemical capacitors based on carbon nanotubes, graphene and their composites. Their current challenges and future prospects are also discussed.
文摘Two Minkowski functionals were tested in the capacity of morphological descriptors to quantitatively compare the arrays of vertically-aligned graphene flakes grown on smooth and nanoporous alumina and silica surfaces. Specifically, the Euler-Poincaré characteristic and fractal dimension graphs were used to characterize the degree of connectivity and order in the systems, i.e. in the graphene flake patterns of petal-like and tree-like morphologies on solid substrates, and meshlike patterns (networks) grown on nanoporous alumina treated in low-temperature inductivelycoupled plasma. It was found that the Minkowski functionals return higher connectivity and fractal dimension numbers for the graphene flakepatterns with more complex morphologies, and indeed can be used as morphological descriptors to differentiate among various configurations of vertically-aligned graphene flakes grown on surfaces.
文摘The results of systematic numerical studies of graphene flakes growth in low-temperature arc discharge plasmas are presented. Diffusion-based growth model was developed, verified using the previously published experiments, and used to investigate the principal effects of the process parameters such as plasma density, electron temperature, surface temperature and time of growth on the size and structure of the plasma-grown graphene flakes. It was demonstrated that the higher growth temperatures result in larger graphene flakes reaching 5 μm, and simultaneously, lead to much lower density of the carbon atoms adsorbed on the flake surface. The low density of the carbon adatoms reduces the probability of the additional graphene layer nucleation on surface of growing flake, thus eventually resulting in the synthesis of the most valuable single-layered graphenes.
文摘Graphene platelet networks (GPNs) were deposited onto silicon substrates by means of anodic arc discharge ignited between two graphite electrodes.Substrate temperature and pressure of helium atmosphere were optimized for the production of the carbon nanomaterials.The samples were modified or destroyed with different methods to mimic typical environments responsible of severe surface degradation.The emulated conditions were performed by four surface treatments,namely thermal oxidation,substrate overheating,exposition to glow discharge,and metal coating due to arc plasma.In the next step,the samples were regenerated on the same substrates with identical deposition technique.Damaging and re-growth of GPN samples were systematically characterized by scanning electron microscopy and Raman spectroscopy.The full regeneration of the structural and morphological properties of the samples has proven that this healing method by arc plasma is adequate for restoring the functionality of2D nanostructures exposed to harsh environments.
文摘Cold atmospheric plasmas are currently gaining increasing attention for cancer therapy.However,very limited studies regarding the interaction mechanisms between plasma species and tissues are available.We report the interaction of plasma produced species(^(*)OH and HO_(2)^(*))with gap junction by employing reactive molecular dynamics simulations.Our results indicate ^(*)OH and HO_(2)^(*) radicals can chemically react with N-terminal of gap junction resulting in its structural damage.There are two breaking mechanisms being identified:C-N peptide bonds and C-C bonds can be damaged by ^(*)OH and HO_(2)^(*) radicals,respectively.Our findings could be particularly important for understanding the plasma-generated reactive species triggering bystander effect based on gap junction intercellular communication.
