Derrouiche Salim, Gravejat Paul, Bianchi Daniel
Contribution from the Laboratoire d'Application de la Chimie à l'Environnement (LACE), UMR 5634, Université Claude Bernard, Lyon-I, Batiment 303, 43 Boulevard du 11 Novembre 1918, 69622 Villeurbanne, France.
J Am Chem Soc. 2004 Oct 13;126(40):13010-5. doi: 10.1021/ja0470719.
The heats of adsorption of two linear CO species adsorbed on the Au degrees particles (denoted L(Au degrees)) and on the Ti(+delta) sites (denoted L(Ti+delta)) of a 1% Au/TiO(2) catalyst are determined as the function of their respective coverage by using the AEIR procedure (adsorption equilibrium infrared spectroscopy) previously developed. Mainly, the evolutions of the IR band area of each adsorbed species (2184 cm(-1) for L(Ti+delta) and at 2110 cm(-1) for L(Au degrees)) as a function of the adsorption temperature T(a), at a constant CO adsorption pressure P(CO), provide the evolutions of the coverages theta(LTi+delta) and theta(LAu degrees ) of each adsorbed CO species with T(a) in isobar conditions that give the individual heats of adsorption. It is shown that they linearly vary from 74 to 47 kJ/mol for L(Au degrees ) and from 50 to 40 kJ/mol for L(Ti+delta) at coverages 0 and 1, respectively. These values are consistent with literature data on model Au particles and TiO(2). In particular, it is shown that the mathematical formalism supporting the AEIR procedure can be applied to literature data on Au-containing solids (single crystals and model particles).
通过使用先前开发的AEIR程序（吸附平衡红外光谱法），测定了吸附在1%Au/TiO₂催化剂的Au⁰颗粒（记为L(Au⁰)）和Ti(⁺δ)位点（记为L(Ti⁺δ)）上的两种线性CO物种的吸附热，该吸附热是其各自覆盖度的函数。主要是，在恒定的CO吸附压力P(CO)下，每种吸附物种（L(Ti⁺δ)在2184 cm⁻¹处，L(Au⁰)在2110 cm⁻¹处）的红外波段面积随吸附温度T(a)的变化，给出了在等压条件下每种吸附CO物种的覆盖度θ(LTi⁺δ)和θ(LAu⁰)随T(a)的变化情况，从而得到各自的吸附热。结果表明，在覆盖度分别为0和1时，L(Au⁰)的吸附热从74 kJ/mol线性变化到47 kJ/mol，L(Ti⁺δ)的吸附热从50 kJ/mol线性变化到40 kJ/mol。这些值与关于模型Au颗粒和TiO₂的文献数据一致。特别地，结果表明支持AEIR程序的数学形式可以应用于含Au固体（单晶和模型颗粒）的文献数据。
