Tiny nanoparticles of organometallic polymers through the direct disassembly-assisted synthesis strategy for hydrogen peroxide sensing

Abstract

Hybrid nanostructures are a class of promising functional materials with a broad range of applications. Structural control has been proven to be versatile to optimize the functions and properties of the nanomaterials. Although polymer/inorganic hybrid nanoparticles have been achieved through self-assembly of block copolymers, synthesis of hybrid nanoparticles of small size (≤20 nm) remains challenging. Herein, we developed a conceptually new approach for the efficient and scalable synthesis of polymer/inorganic hybrid nanoparticles with well-defined shape and tiny size through the direct disassembly-assisted synthesis (DDAS) strategy. Incorporating cyanoferrate into polypeptides led to disassembly of large hexagonally-packed structures of polypeptide α-helices into small aggregates. Subsequent coordination polymerization of the cyanoferrate groups with Fe³⁺ in aqueous media afforded polypeptide/Prussian blue (PB) hybrid nanoparticles with well-defined core–shell structures. Hybrid nanoparticles were thoroughly characterized. Morphological and microstructural analyses showed that the hybrid nanoparticles had a small size of approximately 18 nm and crystalline PB phase. Taking advantage of the tiny size and crystalline PB phase, the hybrid nanoparticles showed excellent electrocatalytic activity toward the reduction of hydrogen peroxide. Such a direct disassembly-assisted synthesis of polymer/inorganic tiny nanoparticles provides a family of functional nanomaterials useful for biosensing and nanodevice applications.