Nitrogen adsorption and thin surface nitrides on Cu(111) from first-principles

Soon, Aloysius; Wong, Lindee; Lee, Michael; Todorova, Mira; Delley, B.; Stampfl, Catherine

doi:10.1016/j.susc.2007.07.011

Cited by 39 publications

(27 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…3(a) illustrates that stoichiometric samples behave as a semiconductor with an indirect absolute gap of 0.32 eV and direct gaps of 1.09 and 0.87 eV at the T and R points, respectively. This calculated indirect gap value is in between those (0.13 eV and 0.40 eV) predicted by different first principles approaches [7,24,[35][36][37]. As shown in Fig.…”

Section: Resultssupporting

confidence: 73%

Electronic structure of copper nitrides as a function of nitrogen content

et al. 2013

View full text Add to dashboard Cite

The nitrogen content dependence of the electronic properties for copper nitride thin films with an atomic percentage of nitrogen ranging from 26 ± 2 to 33 ± 2 have been studied by means of optical (spectroscopic ellipsometry), thermoelectric (Seebeck), and electrical resistivity measurements. The optical spectra are consistent with direct optical transitions corresponding to the stoichiometric semiconductor Cu 3 N plus a free-carrier contribution, essentially independent of temperature, which can be tuned in accordance with the N-excess. Deviation of the N content from stoichiometry drives to significant decreases from -5 to -50 uV/K in the Seebeck coefficient and to large enhancements, from 10~3 up to 10 O cm, in the electrical resistivity. Band structure and density of states calculations have been carried out on the basis of the density functional theory to account for the experimental results.

show abstract

Section: Resultssupporting

confidence: 73%

Electronic structure of copper nitrides as a function of nitrogen content

et al. 2013

View full text Add to dashboard Cite

show abstract

“…For adsorption of N on Cu ͑110͒, in addition to adsorption on the unreconstructed substrate, various surface reconstructions, including a surface nitride reconstruction, were considered. The most stable adsorption phase was found to be the Cu ͑110͒-p͑2 ϫ 3͒-4N structure, where the surface reconstructs into a configuration which closely resembles that of a layer of bulk Cu 3 N. Using the Gibbs-surface free energy and including the results of our previous investigation into N adsorption on Cu ͑111͒, 39 we obtain the predicted Cu particle nanomorphology based on the Wulff construction. At low nitrogen chemical potential, the clean Cu ͑111͒ facets dominate the crystal shape, while just prior to the formation of bulk copper nitride surfaces, the Cu crystal is composed of only Cu ͑100͒-c͑2 ϫ 2͒-N and Cu ͑110͒-p͑2 ϫ 3͒-4N facets.…”

Section: Discussionmentioning

confidence: 99%

“…The findings for the N/Cu ͑100͒ and N/Cu ͑110͒ structures are compared with the results of our previous study of nitrogen adsorption on Cu ͑111͒. 39 Knowing that the morphology of a nanoparticle could be a factor responsible for their physical and chemical properties ͑and thus functionality͒, we proceed to investigate the FIG. 1.…”

Section: Introductionmentioning

confidence: 96%

Morphology of copper nanoparticles in a nitrogen atmosphere: A first-principles investigation

et al. 2008

Self Cite

View full text Add to dashboard Cite

We perform first-principles density-functional-theory calculations to determine the stability and associated physical and electronic properties of different adsorption phases of N on Cu ͑100͒ and Cu ͑110͒ substrates for coverages ranging from 0.125 to 1 monolayer ͑ML͒. For N on Cu ͑100͒, we consider adsorption in fourfold hollow sites while for N on Cu ͑110͒, we consider various adsorption sites including N-induced missing-row surface reconstructions and the surface nitridelike, "pseudo-͑100͒" reconstruction. We report the atomic and electronic structure and compare with analogous results for N/Cu ͑111͒. By combining results from our previous study of the N/Cu ͑111͒ system with the current investigations, we predict the possible morphology of a Cu crystal in different nitrogen environments by performing a Wulff construction at appropriate chemical potentials of nitrogen. We also find that all low-energy N/Cu surface structures-namely, Cu ͑100͒-c͑2 ϫ 2͒-N and the surface nitrides found on Cu ͑110͒ and Cu ͑111͒-share a common geometric feature: i.e., surface nanopatterns resembling 1 atomic layer of Cu 3 N ͑100͒. These nanopatterned structures exist for a narrow range of nitrogen chemical potentials before the onset of bulk Cu 3 N, unless kinetically hindered. This qualitative behavior of the predicted formation of thin-surface nitridelike structures prior to the bulk nitride material is very similar to that for transition-metal surfaces in an oxygen atmosphere, where surface oxidelike structures are predicted to be thermodynamically stable prior to bulk oxide formation.

show abstract

“…The coverage dependent properties of oxygen adsorption on transition metals such as platinum [10][11][12], ruthenium [13], rhodium [14], palladium [15,16], gold [17], and copper [18] have been studied using DFT. Additionally, work has also been done to study adsorption of other adsorbates such as sulfur on Cu, Ag, and Pd [19,20], and nitrogen on Ru [21] and Cu [22,23] using DFT.…”

Section: Introductionmentioning

confidence: 99%