@Article{cmc.2025.067722,
AUTHOR = {Yuanyuan Xiong, Tong Wu, Lixin Sun, Mingyu Hu, Jie Yu},
TITLE = {Thermodynamics Calculation of Reaction Synthesis Pathways for Ag-Al<sub>2</sub>O<sub>3</sub> Powder By First-Principles Calculations},
JOURNAL = {Computers, Materials \& Continua},
VOLUME = {85},
YEAR = {2025},
NUMBER = {3},
PAGES = {4473--4489},
URL = {http://www.techscience.com/cmc/v85n3/64155},
ISSN = {1546-2226},
ABSTRACT = {Ag/Al<sub>2</sub>O<sub>3</sub> powders are highly effective catalytic materials utilized in the epoxidation of ethylene to produce ethylene oxide. One of the critical challenges in this catalytic process is the stability of nano-sized Ag particles, especially during high-temperature catalysis. However, this issue can be effectively addressed through <i>in-situ</i> reaction synthesis. To gain a deeper understanding of the underlying mechanisms, the phase transformation process and the thermodynamic mechanism of the oxidation reaction in the Ag/Al<sub>2</sub>O<sub>3</sub> system have been investigated using first-principles thermodynamic calculations in conjunction with traditional thermodynamic data. These calculations, whose accuracy has been verified, provide valuable insights into the behavior of Ag and Al under different conditions. The results indicate that, during AgAl solid-solution oxidation, Ag-containing Al preferentially forms the stable intermediate phase Ag<sub>2</sub>Al instead of undergoing direct oxidation; this pathway becomes thermodynamically more favorable at higher Ag concentrations. With increasing temperature, Ag<sub>2</sub>Al is further oxidized to yield Ag and Al<sub>2</sub>O<sub>3</sub>. It is also found that above 237°C, Ag<sub>2</sub>O and AgAlO<sub>2</sub> become unstable. The overall reaction pathway is solid solution→Ag<sub>2</sub>Al→Ag + Al<sub>2</sub>O<sub>3</sub>. This comprehensive study provides a robust theoretical calculation basis for the development and optimization of <i>in-situ</i> reaction-synthesized Ag/Al<sub>2</sub>O<sub>3</sub> powder composite materials, which have significant potential for practical applications in catalysis.},
DOI = {10.32604/cmc.2025.067722}
}