Progress in atomistic modelling of nanoparticle coalescence

Coalescence (or sintering) of two or more nanoparticles into larger nanoparticles or particle aggregates is one of the fundamental processes that differentiate nano-matter from bulk matter, and plays a vital role in determining shape, size, structure, and resultant properties vital for various applications. Computational methods, especially atomistic simulations, have been employed over the past decades to reveal the dynamics of nanoparticle coalescence at the atomic level. Integrated findings from various simulations enhance our understanding of nanoparticle interaction and merging mechanisms. Understanding these mechanisms can guide the design of nanoparticles with tailored properties for diverse applications from printed and flexible electronics to catalysis and pigmentations, and from drug delivery and energy storage to nanoparticle-based neuromorphic computation devices. This review aspires to distil our current knowledge and understanding of nanoparticle coalescence in a compact and visual way, so that it can be used as reference and starting point for future computational studies and as guidance for the experimental fabrication of nanoparticulated matter.