Thermoelectric Properties of Composite Nanoparticle Array with Protoporphyrin Molecule Junctions

Abstract

Composite nano-structures have many interesting properties and potential applications. For a molecule-nanoparticle (NP) composite array, its properties may strongly depend on the molecules on/between NPs. For instance, the resistance of NP composite film sensitively change with the length of surface molecules,[1,2] and could be applied to vapor sensors.[3] In this report, we show a homemade system to measure thermoelectric properties of protoporphyrin molecule junctions in molecule-NP composite array. Many kinds of metal-protoporphyrin molecules (Heme, Hematin, Zinc-protoporphyrin, Cobaltic-protoporphyrin, Protoporphyrin IX) and dl-cysteine/cysteamine molecules were studied. We found metal ion in protoporphyrin molecule is matter for the Seebeck coefficient of molecule-NP composite array.