A Highly Conductive n-Type Coordination Complex with Thieno[3,2-b]thiophene Units: Facile Synthesis, Orientation, and Thermoelectric Properties

Abstract

An organometallic nickel complex containing thieno­[3,2-b]­thiophene units was designed and synthesized. Composite films of the resulting nickel complex and polyvinylidene difluoride, which can be fabricated via a simple solution process under atmospheric conditions, exhibit remarkably high n-type conductivity (>200 S cm–1). Moreover, the thermoelectric power factor of the n-type composite film was proven to be air stable. A grazing-incidence wide-angle X-ray diffraction analysis indicated a significant impact of introducing the thieno­[3,2-b]­thiophene core into the backbone of the nickel complex on the orientation within the composite films.

Base-Assisted Polymerizations of Elemental Sulfur and Alkynones for Temperature-Controlled Synthesis of Polythiophenes or Poly(1,4-dithiin)s

“…Since the discovery of electrically conducting polyacetylene in the 1970s, , research enthusiasm on conjugated polyheterocycles such as polypyrroles, polythiophenes, polycarbazoles, and polyfluorenes has emerged and continuously grew. Among all the semiconducting polymers, polythiophenes have attracted much attention and have been extensively utilized in a variety of high-tech applications including organic solar cells, , electronic skins, thermoelectric materials, , field effect transistors, − photodetectors, , and so on, owing to their unique advantages such as high conductivity, environmental and thermal stability, ease of structural modification, and suitable energy levels. , Transition-metal-catalyzed coupling reactions, oxidative polymerization, acid-catalyzed polymerization, electrochemical polymerization, photoinduced polymerization, and solid-phase polymerization were normally used for the preparation of polythiophenes, which generally required synthesis of thiophene-containing monomers. With the growing demand on functional polythiophene materials, it is of great significance to develop new polymerization strategies with high efficiency, high convenience, and low cost from simple, cheap, and abundant sulfur-containing monomers.…”