From Nanoscopic to Macroscopic Materials by Stimuli-Responsive Nanoparticle Aggregation.

Stimuli-responsive nanoparticle (NP) aggregation plays an increasingly important role in regulating NP assembly into microscopic superstructures, macroscopic 2D and 3D functional materials. Diverse external stimuli have been widely used to adjust the aggregation of responsive NPs, such as light, temperature, pH, electric and magnetic fields. Many unique structures based on responsive NPs have been constructed including disordered aggregates, ordered superlattices, structural droplets, colloidosomes and bulk solids. In this review, we summarize the strategies for NP aggregation by external stimuli, and their recent progress ranging from nanoscale aggregates, microscale superstructures to macroscale bulk materials along the length scales as well as their applications. This review also discusses the future opportunities and challenges for designing functional materials through NP aggregation at different length scales. This article is protected by copyright. All rights reserved.