Atomic Scale Studies of Segregation at Ceramic/Metal Heterophase Interfaces

Evidence of oxygen segregation at Ag/MgO interfaces

“…Detailed knowledge of this eect is of great importance, as the solute atoms can in¯uence the characteristics of the material [8] as observed, for instance, in the interfacial accumulation of Ag at MgO/Cu {222}, and of Sb/ Zn at Ag/Mn 3 O 4 [9,10]. Furthermore, the segregation of oxygen modi®es the chemical composition of metal/oxide interfaces as a function of the activity of oxygen.…”

“…To investigate metal/oxide interphase boundaries, spatially resolved EDX [30], surface spectroscopy [31], high resolution electron microscopy (HREM) [5, 11±13, 21, 23, 32±34], and ®eld-ion microscopy with atom-probe (FIP-AP) [9,14,15,35] have so far been applied successfully. Electron energy loss spectroscopy (EELS) is also useful in performing such examinations, since it allows the bonding states of chemical elements at interfaces to be determined on a nanometre scale by analysing the near edge ®ne structure (ELNES) of an EELS spectrum [7,24,28,29,36,37].…”

“…This particular preparation method is advantageous in that¯at (on an atomic scale) and low-energetic semi-coherent interfaces with a small lattice mis®t of d 3X17 are forming [4,5,9,38] as the precipitates (here of MgO) are growing freely with respect to shape and orientation. Furthermore, an equilibrium between oxygen at the interface and oxygen dissolved in the matrix is easy to attain, due to the high diusivity of oxygen in silver, even at moderate temperatures of about 700 K [39].…”

A graph-theoretic approach for characterization of precipitates from atom probe tomography data

“…Of particular interest is the analysis and classification of precipitate topology, shape, size distributions as well as their interfacial properties [12,22,23,25,13,24]. Addressing this problem can give clear insights into structure-property relationships (especially in the context of energy storage devices) and, thus, help in achieving a larger goal of accelerated materials-by-design [33].…”

First principles slab calculations of the regular Cu/MgO(001) interface

“…Two types of the densely-packed copper/magnesia interfaces have been mainly studied so far, both experimentally and theoretically: Cu/MgO-(0 0 1) and Cu/MgO(1 1 1) [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. The adsorption of copper moieties on the MgO(0 0 1) support was analyzed by means of the Auger electron spectroscopy [1].…”