# Co-assembly of Janus nanoparticles in block copolymer systems

## TL;DR

This paper introduces a mesoscopic simulation method to study how Janus nanoparticles co-assemble within block copolymer systems, revealing their unique aggregation behaviors and potential for ordered material formation.

## Contribution

It presents a novel simulation approach to analyze Janus nanoparticle co-assembly in block copolymers, highlighting their distinct segregation and layered assembly properties.

## Key findings

- Janus nanoparticles form ordered aggregates in block copolymer matrices.
- Janus particles are less disruptive than neutral nanoparticles in lamellar domains.
- Asymmetric Janus nanoparticles can assemble into multiple layers within a block.

## Abstract

Block copolymer are ideal matrices to control the localisation of colloids. Furthermore, anisotropic nanoparticles such as Janus nanoparticles possess an additional orientational degree of freedom that can play a crucial role in the formation of highly ordered materials made of block copolymers. This work presents a mesoscopic simulation method to assert the co-assembly of Janus nanoparticles in a block copolymer mixture, finding numerous instances of aggregation and formation of ordered configurations which can be related to dispersions of pure Janus colloids. Comparison with chemically homogeneous neutral nanoparticles determines that Janus nanoparticles are less prone to induce bridging along lamellar domains, thus being a less destructive way to segregate nanoparticles at interfaces. The combination of asymmetric block copolymer and asymmetric Janus nanoparticles can result in assembly of colloids in an even number of layers within one of the block domains.