Competitive hydrogen bonding and electrostatic interactions-mediated alternating nanoparticles copolymerization

Nanoparticles self-assembly plays a pivotal role in designing new functional structural materials. The manipulation of interactions among nanoparticle building blocks is crucial for achieving assemblies with desired structures and properties. In this work, we assemble binary inorganic nanoparticles into alternating copolymer-like nanostructures by independently regulating hydrogen bonding and electrostatic interactions. The block copolymers grafted on nanoparticles feature oppositely charged groups, where electrostatic attraction drives the linear assembly of nanoparticles into alternate chain configurations. The hydrogen bonding interaction originates from the direct introduction of polyethylene glycol into the systems, serving as hydrogen bond acceptors with the grafted polymer and facilitating the side-by-side assembly of the chain structures. These two forces were observed to compete with each other during the assembly process, and could be precisely controlled by adjusting the quantities of acetic acid and polyethylene glycol, thus regulating the nanoparticle assembly behavior. This work provides a practical framework for the design of muti-force interactions in hierarchical colloid nanomaterials.