Search results for "surface reactivity"
showing 4 items of 4 documents
Temptative Modeling of Surface Reactivity with Oxidizing-Reducing Mixtures on Rutile TiO2-δ
1989
Rutile bears some unique features in regard to oxygen transfer with the outer atmosphere, at high temperatures. It possesses very high chemical diffusivity. This diffusivity becomes apparent while performing reequilibration experiments in a final atmosphere of pure oxygen. Conversely, the oxidizing-reducing reaction with CO/CO2 mixtures at the rutile surface is always a slow process.
Enhanced Surface Ligands Reactivity of Metal Clusters by Bulky Ligands for Controlling Optical and Chiral Properties.
2021
Surface ligands play critical roles in determining the surface properties of metal clusters. However, modulating the properties and controlling the surface structure of clusters through surface‐capping agent displacement remain a challenge. In this work, a silver cluster, [Ag 14 (SPh(CF 3 ) 2 ) 12 (PPh 3 ) 4 (DMF) 4 ] ( Ag 14 ‐DMF , where HSPh(CF 3 ) 2 is 3,5‐bis(trifluoromethyl)benzenethiol, PPh 3 is triphenylphosphine and DMF is N,N‐Dimethylformamide), with weakly coordinated DMF ligands on the surface silver sites, was synthesized by using a mixed ligands strategy (bulky thiolates, phosphines and small solvents). The as‐prepared Ag 14 ‐DMF is a racemic mixture of chiral molecules. Owing …
Dependence of the Lattice Parameter of Magnesium Oxide on Crystallite Size
1966
Lattice parameters were measured on MgO specimens prepared in air between 450° and 1200°C. The lattice parameter, a, decreases with increase in preparation temperature, Tp, and with increase in crystallite size. A hydroxide layer is present on the MgO particles. If MgO is prepared in vacuum, a increases as Tp increases and as crystallite size, D, increases. It is concluded that a dilatant volume stress is imposed by the hydroxide layer. It is also shown that the oxide surface reactivity toward water is linked to the deviation from perfect order ensuing from low preparation temperatures.
Passivity Breakdown: Development and Application of Local Chemical and Electrochemical Probe Methods
2018
Abstract The most identified classes of phenomena at the origin of the passivity breakdown and the electrochemical and chemical factors controlling the induced localized corrosion are summarized before introducing the scientific concepts at the origin of the design of the local probe techniques used in recent advances in understanding localized corrosion processes. Examples concerning the surface reactivity of aluminium alloys are presented to support a final discussion on the needs for experimental developments with capabilities to support modelling.