Photoluminescent Gold Nanoclusters in Soft Matrices

Abstract

Photoluminescent gold nanoclusters (AuNCs), composed of several to tens of gold atoms, are versatile ultrasmall nanomaterials that show promise in applications like imaging, sensing, lighting, and catalysis. However, the inferior photoluminescence performance and lack of functional properties, have hindered AuNCs from extensive application. This thesis discusses AuNCs confined in three types of soft matrices, namely assemblies, double-layered structures, and polymers. Confinement of AuNCs in the soft matrices can result in great performance improvement and interesting functional properties. The mechanisms behind the performance enhancement and functional properties are studied and discussed. The AuNCs in the soft matrices show potential for various applications. Publication 1 establishes supraparticles as a promising soft matrix for AuNCs, achieving a significant improvement in photoluminescence emission brightness and resistance to photobleaching. Publication 2 reports a dual-layered oxide shell as an effective matrix for AuNCs, achieving comprehensive enhancement in stability.Publication 3 introduces a simple, direct strategy for both generation and encapsulation of AuNCs in the polymer film, exhibiting moderate photoluminescence efficiency and excellent shelf and photo-stability. Publication 4 outlines that confinement of AuNCs in the aliphatic tertiary amine group-rich polymer scaffold leads to pH-responsive near-infrared emission, promising great bio-application potential. Overall, these works demonstrate various strategies for obtaining gold nanoclusters with improved photoluminescence performance and functional properties.