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linweiguo0(金币+4):谢谢应助 辛苦了
酸性前面有专帖介绍
碱性可以看看http://www.muchong.com/bbs/viewthread.php?tid=472557&fpage=2——碱土金属氧化物、氢氧化物作为碱催化反应催化剂的优化（reveiw）
broad terms, the main techniques that are used frequently are the following: titration, spectroscopic investigations, and test reactions. These methods, in conjunction with adsorption and temperature-programed desorption (TPD) of probe molecules, give information about the nature, number, strength, and reactivity of basic sites on solid catalysts.
A. TITRATION METHODS
The number of basic sites of different strengths can be evaluated by titration
using organic acids (benzoic acid, acrylic acid, phenol, etc.) in water or organic
solvents
The strength of the basic sites can be expressed on a scale given by the H
function defined by the equation
B. SPECTROSCOPIC METHODS
Techniques such as X-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonance (EPR) spectroscopy, have been applied to determine the basic properties of solids (2). The usefulness of XPS is based on the fact that the electronpair donating ability of a solid base may be directly related to the O1s binding energy. A good correlation between effective oxygen charge and the O1s binding energy was found for single metal oxides (44). EPR, combined with the adsorptionof probe molecules such as tetracyanoethylene and perylene。
Among the spectroscopic techniques, one of the most widely used to characterize the basic properties of alkaline earth metal oxides is infrared (IR) spectroscopy of adsorbed probe molecules
Temperature-programed desorption of the probe molecules is frequently used to
measure the number and strength of basic sites, and the most commonly used probe molecule is CO2. According to this method, the strength of the basic sites is represented by the desorption temperature, and the peak area in the TPD plot determines the number of basic sites |
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