Revealing the graphene growth mechanism at the atomic-scale is of great importance for achieving high quality graphene. However, the lack of direct experimental observation and density functional theory (DFT) verification hinders a comprehensive understanding of the structure of the carbon clusters and evolution of the graphene growth on surface. Here, we report an in-situ low-temperature scanning tunneling microscopy (LT-STM) study of the elementary process of chemical vapor deposition (CVD) graphene growth via thermal decomposition of methane on Cu(110), including the formation of monodispersed carbon clusters at the initial stage, the graphene nucleation and the ripening of graphene islands to form continuous graphene film. STM measurement, supported by DFT calculations, suggests that the carbon clusters on the surface are C2H5. It is found that graphene layers can be joined by different domains, with a relative misorientation of 30°. These graphene layers can be decoupled from Cu(110) through low temperature thermal cycling.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3961735 | PMC |
http://dx.doi.org/10.1038/srep04431 | DOI Listing |
Amino Acids
January 2025
Faculty of Natural Sciences, University of SS Cyril and Methodius, 91701, Trnava, Slovakia.
Four aliphatic amino acids-α-aminobutyric acid (AABA), β-aminobutyric acid (BABA), α-aminoisobutyric acid (AAIBA) and β-aminoisobutyric acid (BAIBA) were investigated in water as a solvent by two quantum chemical methods. B3LYP hybrid version of DFT was used for geometry optimization and a full vibrational analysis of neutral molecules, their cations and anions in the canonical and zwitterionic forms (6 forms for each species). Ab initio DLPNO-CCSD(T) method was applied in the geometry pre-optimized by B3LYP.
View Article and Find Full Text PDFBiotechnol Biofuels Bioprod
January 2025
Institute of Marine Science and Technology, Shandong University, Qingdao, 266237, Shandong, China.
Coastal wetlands are rich in terrestrial organic carbon. Recent studies suggest that microbial consortia play a role in lignin degradation in coastal wetlands, where lignin turnover rates are likely underestimated. However, the metabolic potentials of these consortia remain elusive.
View Article and Find Full Text PDFJ Environ Manage
January 2025
Hebei University of Environmental Engineering, Qinghuangdao, 066102, China.
The synergistic reduction of air pollutants and carbon dioxide (CO) emissions is a key component in achieving China's strategy of pollution and carbon reduction. This study quantitatively evaluates the spatiotemporal linkages between PM and CO emissions, as well as the benefits of sustained synergistic control, across over 360 Chinese cities from 2005 to 2020. We employed spatiotemporal analysis, coupled coordinateness modeling, the Hurst index, and generalized linear mixed modeling (GLMM).
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
January 2025
Institute of Solid State Physics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China; Key Laboratory of Photovoltaic and Energy Conservation Materials, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China. Electronic address:
The relationship between human health and patulin (PAT) in the diet is a complex and intertwined one. The development of a sensing approach for the field detection of patulin is crucial, as the current approach lacks real-time detection capabilities and is costly in terms of material and technology. This paper presents a portable ratiometric fluorescence sensor that can be used to rapidly, accurately, and efficiently detect patulin in food items at the point of origin.
View Article and Find Full Text PDFEnviron Sci Technol
January 2025
State Key Laboratory of Heavy Oil Processing, Key Laboratory of Optical Detection Technology for Oil and Gas, College of Science, China University of Petroleum, Beijing 102249, PR China.
The purification efficiency of autoexhaust carbon strongly depends on the heterogeneous interface structure between active metal and oxide, which can modulate the local electronic structure of defect sites to promote the activation of reactant molecules. Herein, the high-dispersion CuO clusters supported on the well-defined CeO nanorods were prepared using the complex deposition slow method. The formation of heteroatomic Cu-O-Ce interfacial structural units as active sites can capture electrons to achieve activation of the NO and O molecules.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!