Aqueous Solvation and Surface Oxidation of the Cu7 Nanoparticle: Insights from Theoretical Modeling

作者：Stenlid Joakim H; Johansson A Johannes; Kloo Lars; Brinck Tore^*

来源：Journal of Physical Chemistry C, 2016, 120(3): 1977-1988.

DOI：10.1021/acs.jpcc.5b11361

The current understanding on: the behavior of nano particles in solution is limited. We have studied tho effects of the aqueous environment on the anoxic oxidation of a Cu-7 riannpartide using a range of different computational solvation models. On the basis of a series of hydroxylated Cu-7(H2O)(y)(OH)x structures, the performance of standard continuum models have been compared to discrete models including up to, and beyond, the second solvation layer. Both full quantum chemical 4 (DFT: PBEO-D3) and QM/MM (PBEO/EPP1) computations were employed in the analysis. The Cu-7 structures were solvated in water nanodroplets and studied by molecular dynamics simulations. On the basis of the simulations, we were able to identify new modes of H2O interactions with the Cu(7)particle, modes that were previously considered unbeneficial. All solvation models favor the "Same equilibrium oxidation state corresponding to a Cu(I)OH surface species. However, for quantitative energy comparison of similar- systems, our results suggest the use of a combined water cinst07cniftinuum model including at least a first explicit solvation shell for energetic comparisons. Nevertheless, the second solvatiOn:thell is -important for identifying representative inner solvation shell structures.

• 出版日期2016-1-28