A New Approach to the Synthesis of Nanocrystal Conjugated Polymer Composites

TL;DR

This paper introduces a novel one-pot synthesis method for creating PbS nanocrystal-polymer composites, eliminating surfactant removal and solvent incompatibility issues, resulting in highly ordered, size-controlled nanocrystals within a conjugated polymer.

Contribution

A new one-pot synthesis approach for PbS nanocrystals in conjugated polymers that simplifies fabrication and improves control over nanocrystal size and order.

Findings

Nanocrystals grown directly in polymer matrix

Composite is highly ordered and uniform

Nanocrystal size can be precisely controlled

Abstract

A novel one pot process has been developed for the preparation of PbS nanocrystals in the conjugated polymer poly 2-methoxy,5-(2 -ethyl-hexyloxy-p-phenylenevinylene) (MEH-PPV). Current techniques for making such composite materials rely upon synthesizing the nanocrystals and conducting polymer separately, and subsequently mixing them. This multi-step technique has two serious drawbacks: templating surfactant must be removed before mixing, and co-solvent incompatibility causes aggregation. In our method, we eliminate the need for an initial surfactant by using the conducting polymer to terminate and template nanocrystal growth. Additionally, the final product is soluble in a single solvent. We present materials analysis which shows PbS nanocrystals can be grown directly in a conducting polymer, the resulting composite is highly ordered and nanocrystal size can be controlled.