Interface-assisted assembly of colloidal particles: recent advances in the wet-process-based fabrication of functional materials

Interface-assisted assembly of colloidal particles has emerged as a versatile platform for constructing functional materials with collective properties and hierarchical architectures that cannot be achieved by isolated particles alone. This review summarizes recent advances in wet-process-based colloidal assembly at interfaces, with particular emphasis on representative studies reported over the past several years. Particle deposition on solid substrates via solvent evaporation is first described, highlighting self-assembly dynamics and coffee-ring suppression, as well as strategies for crack-free films through interparticle bridging and solvent engineering. We then discuss interface-assisted fabrication of three-dimensional particle assemblies using emulsions, Pickering emulsions, and liquid marbles, which enables spherical, fibrous, and polyhedral architectures exhibiting structural coloration as well as mechanical and chemical functionalities. Two-dimensional assemblies at interfaces are also reviewed, including Langmuir–Blodgett methods and electrophoretic deposition. Furthermore, emerging functions such as superhydrophobicity, plasmonic anisotropy, high-toughness elastomers, and bio-relevant soft materials are addressed. Finally, we outline current challenges and future perspectives, emphasizing the importance of interdisciplinary approaches integrating colloid chemistry, polymer science, and interface engineering to expand the scope of interface-enabled colloidal materials.