Energy barriers for trimethylaluminum reaction with varying surface hydroxyl density

Energy barriers for trimethylaluminum (TMA) reaction with varying surface hydroxyl (–OH) density were investigated using density functional theory. When the surface –OH density increased from 0 to 6.8/nm2 on Si (0 0 1) surfaces, the energy barrier for TMA reaction with the surfaces decreased due to attractive interactions between TMA and –OH. When the surface –OH density further increased to 9.2/nm2 on a-SiO2 (0 0 1) surfaces, however, the trend was reversed. This was because the attractive interactions between TMA and –OH were decreased due to the attractive interactions of –OHʹs themselves via hydrogen bond at this high surface –OH density.