It is demonstrated that surface vibrational spectroscopy can be used to probe local ordering of adsorbates and the nature of inter-adsorbate interactions through dynamical dipole coupling among neighboring adsorbates. Our studies show that for CO adsorbed on Cu(100), first and second nearest neighbor interactions are repulsive. This repulsion prevents the formation of long range ordered structu...

Where V is the adsorbed gas volume at relative pressure of P/P0; V0 maximum volume of adsorbed gas in micropores; R the universal gas constant (0.0083144 kJ/K mol); T the analysis temperature (K); and E is the adsorption energy (kJ/mol). From the linearized plot of DR equation, V0 and E are calculated. By using a conversion factor the equivalent liquid volume or micropore volume can be calculat...

Adsorption microcalorimetry measures the energetics of adsorbate-surface interactions and can be performed by use of several different techniques. This review focuses on three methods: single-crystal adsorption calorimetry (SCAC), isothermal titration calorimetry (ITC), and electrochemical adsorption calorimetry. SCAC is a uniquely powerful technique that has been applied to a variety of atoms ...

We study the underpotential deposition of Cu on single-crystal Au(111) electrodes in sulfate-containing electrolytes by a combination of computational statistical-mechanics based lattice-gas modeling and experiments. The experimental methods are in situ cyclic voltammetry and coulometry and ex situ Auger electron spectroscopy and low-energy electron diffraction. The experimentally obtained volt...

The study investigated the optimum conditions for adsorption of phenol from aqueous solution using plantain peels activated carbon. Low-cost adsorbents were produced unripe peel by both physical and chemical activation processes at carbonization temperature 400oC 2 hrs. unwashed carbon (UPPAC) was with ZnCl2 impregnation ratio 1:2 while (NAPPC) not impregnated any chemical. carbons characterize...

The d-band center model of Hammer and Nørskov is widely used in understanding and predicting catalytic activity on transition metal (TM) surfaces. Here, we demonstrate that this model is inadequate for capturing the complete catalytic activity of the magnetically polarized TM surfaces and propose its generalization. We validate the generalized model through comparison of adsorption energies of ...

A model of gas–surface reactivity is developed based on the ideas that ~a! adsorbate chemistry is a local phenomenon, ~b! the active system energy of an adsorbed molecule and a few immediately adjacent surface atoms suffices to fix microcanonical rate constants for surface kinetic processes such as desorption and dissociation, and ~c! energy exchange between the local adsorbate–surface complexe...

Femtosecond transient absorption spectroscopy has been used to investigate the electron-electron scattering dynamics in sulfate-covered gold nanoparticles of 2.5 and 9.2 nm in diameter. We observe an unexpected retardation of the absolute internal thermalization time compared to bulk gold, which is attributed to a negative feedback by the vibrationally excited sulfate molecules. These hot adsor...