Effects of pressure on volatilisation of pure Bi nanoparticles and Bi–Fe core–shell nanoparticles during continuous heating: a molecular dynamics study.

In the present work, the molecular dynamics study method has been utilised to investigate the effects of pressure on the volatilisation of pure Bi nanoparticles and Bi–Fe core–shell nanoparticles during continuous heating. Computational total energy curves between 300 and 2000 K are used to explore the structural changes of nanoparticles under different pressures. On the other hand, the radial distribution function is examined to determine the structural evolution of a system. The calculated root mean square displacement curves under pressures of 0–5 GPa between 300 and 2000 K are employed to explore the diffusion of Bi element and the calculated volatilisation rate of Bi element is used to quantitatively obtain the volatilisation characteristics. The volatilisation patterns of pure Bi nanoparticles and Bi–Fe core–shell nanoparticles are different under different temperatures and pressures. The results show that the volatilisation of Bi element is increasing during the heating from 300 to 2000 K, and the volatilisation decreases with the increase of pressure. Furthermore, the Fe shell can effectively decrease the volatilisation of the Bi element. [ABSTRACT FROM AUTHOR]