English
资源说明：Aluminum nitride (AlN) is used extensively in the
semiconductor industry as a high-thermal-conductivity insulator, but
its manufacture is encumbered by a tendency to degrade in the
presence of water. The propensity for AlN to hydrolyze has led to its
consideration as a redox material for solar thermochemical ammonia
(NH3) synthesis applications where AlN would be intentionally
hydrolyzed to produce NH3 and aluminum oxide (Al2O3), which
could be subsequently reduced in nitrogen (N2) to reform AlN and
reinitiate the NH
3 synthesis cycle. No quantitative, atomistic
mechanism by which AlN, and more generally, metal nitrides react
with water to become oxidized and generate NH3 yet exists. In this
work, we used density-functional theory (DFT) to examine the
reaction mechanisms of the initial stages of AlN hydrolysis, which
include: water adsorption, hydroxyl-mediated proton diffusion to form NH3, and NH3 desorption. We found activation barriers
(Ea) for hydrolysis of 330 and 359 kJ/mol for the cases of minimal adsorbed water and additional adsorbed water, respectively,
corroborating the high observed temperatures for the onset of steam AlN hydrolysis. We predict AlN hydrolysis to be kinetically
limited by the dissociation of strong Al−N bonds required to accumulate protons on surface N atoms to form NH3.
本源码包内暂不包含可直接显示的源代码文件，请下载源码包。
