Constructing complex matters with unique functions is one of the goals of nanoparticle self-assembly. In this article we review the basic principle of nanoparticles self-assembly and discuss the interactions between nanoparticles to regulate selfassembled structures and materials with desirable properties. Based on these principles, high quality structures from zero to three dimensions can be prepared such as colloidal molecules, nanochains, colloidal crystals and photonic crystals. We summarize the important advances of assembled structures in sensing, optoelectronic devices, display, drug delivery and biomedical diagnostics in 2020. Finally, we propose the challenges of building new substances in this field.

self-assembly  /  nanoparticles  /  nano-printing  /  multilevel structures  /  functional materials