The stability of finite-sized graphene nanostructures under different conditions is contingent on the stability of the highly reactive undercoordinated atoms around the circumference. Chemical passivation is a convenient way of stabilizing the edges and corners, provided the conditions support adsorption. In this paper we examine the stabilities of hydrogen, oxygen, hydroxyl, and water functionalization of the edges of graphene nanoflakes using a combination of ab initio thermodynamics and self-consistent charge density functional tight-binding simulations. We find that the adsorption of hydrogen and oxygen on graphene nanoflakes is selective and sensitive to the edge and corner structure and the local environment. Under hydrogen-rich conditions (or in vacuo), we find that armchair edges are preferred, whereas under oxygen-rich conditions the stability of the zigzag edge is enhanced. In addition to this, we find that the types of corners play an important role, and the presence of acute 60° corners is thermodynamically preferred, particularly under humid conditions. In each case, the adsorption efficiency is related to the temperature and the pressure, which may be used to stabilize one type of structure or another.
Problems associated with the computation of time-correlation functions using extensions of equilibrium perturbation theory are reviewed. By making various approximations to the first-order term in the expansion of the time displacement operator it is possible to obtain a number of previously published results as special cases of the theory given here. A form of perturbation theory based on the hard-sphere fluid as a reference system is used to investigate the convergence of such theories for the Lennard-Jones fluid.
The authors use a newly fitted gold embedded atom method potential to simulate the initial nucleation, coalescence, and kinetic growth process of vapor synthesized gold nanoparticles. Overall the population statistics obtained in this work seemed to mirror closely recent experimental HREM observations by Koga and Sugawara [Surf. Sci. 529, 23 (2003)] of inert gas synthesized nanoparticles, in the types of nanoparticles produced and qualitatively in their observance ratio. Our results strongly indicated that early stage coalescence (sintering) events and lower temperatures are the mainly responsible for the occurrence of the Dh and fcc based morphologies, while "ideal" atom by atom growth conditions produced the Ih morphology almost exclusively. These results provide a possible explanation as to why the Dh to Ih occurrence ratio increases as a function of nanoparticle size as observed by Koga and Sugawara.
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStatic structure of strongly interacting colloidal particlesI. K. Snook and J. B. HayterCite this: Langmuir 1992, 8, 12, 2880–2884Publication Date (Print):December 1, 1992Publication History Published online1 May 2002Published inissue 1 December 1992https://pubs.acs.org/doi/10.1021/la00048a007https://doi.org/10.1021/la00048a007research-articleACS PublicationsRequest reuse permissionsArticle Views146Altmetric-Citations29LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
Small angle X-ray scattering has been widely used in the past to study the structure of porous materials. The interpretation of the scattering data has been usually been in terms of models based upon discrete pores. As it is now recognized, such models are inadequate to describe a complex system such as coal and in this paper the authors propose to interpret the X-ray scattering from brown coal in terms of fractal concepts.
Radial distribution functions and structure factors are calculated for dilute, but strongly interacting electrostatically stabilized dispersions of small spherical particles. The calculations, based on the usual screened coulomb interaction between the particles, examine the sensitivity of the structure of these colloidal solutions to the background electrolyte concentration, temperature and the particle surface charge.
'/%3e%3c/defs%3e%3cpath fill='%23012169' d='M0 0h10080v5040H0z'/%3e%3cpath stroke='%23fff' stroke-width='.6' d='m0 0 6 3m0-3L0 3' clip-path='url(%23b)' transform='scale(840)'/%3e%3cpath stroke='%23e4002b' stroke-width='.4' d='m0 0 6 3m0-3L0 3' clip-path='url(%23c)' transform='scale(840)'/%3e%3cpath stroke='%23fff' stroke-width='840' d='M2520 0v2520M0 1260h5040'/%3e%3cpath stroke='%23e4002b' stroke-width='504' d='M2520 0v2520M0 1260h5040'/%3e%3cg fill='%23fff'%3e%3cuse xlink:href='%23d' x='2520' y='3780'/%3e%3cuse xlink:href='%23a' x='7560' y='4200'/%3e%3cuse xlink:href='%23a' x='6300' y='2205'/%3e%3cuse xlink:href='%23a' x='7560' y='840'/%3e%3cuse xlink:href='%23a' x='8680' y='1869'/%3e%3cuse xlink:href='%23e' x='8064' y='2730'/%3e%3c/g%3e%3c/svg%3e)
