Discrete Element Simulations of Nanoparticles Synthesis in Wet-operating Stirred Media: Effect of the Particle Material

An increasing number of applications from every branch of science and engineering are relying on the use of nanomaterials due to their peculiar properties with respect to the bulk counterpart and the potential of their employment, for example in the environmental field. Hence, there is a growing need to develop alternative strategies to produce such materials, providing first-rate performances and a fine control over the product specifications through safer and more sustainable processes. Here we focus on a low-energy magnetically driven wet milling technique for the synthesis of metal nanoparticles starting from a bulky solid, as a simple, cheap, and sustainable approach providing numerous advantages, including the minimization of nanoparticle air dispersion and greater control over the final product. We exploit discrete element method simulations to investigate the interactions among the grinding beads and the magnetic stirrer, providing information on the frequency and energy of collisions under various operating conditions, in an attempt to highlight the role of source material in the dynamics of the system. The relation of such data with the properties of the produced nanoparticles allows a fine tuning of the process parameters.