Electronic Properties of Copper(I) Thiocyanate (CuSCN)

With the emerging applications of copper(I) thiocyanate (CuSCN) as a transparent and solution-processable hole-transporting semiconductor in numerous opto/electronic devices, fundamental studies that cast light on the charge transport physics are essential as they provide insights critical for further materials and devices performance advancement. The aim of this article is to provide a comprehensive and up-to-date report of the electronic properties of CuSCN with key emphasis on the structure–property relationship. The article is divided into four parts. In the first section, recent works on density functional theory calculations of the electronic band structure of hexagonal β-CuSCN are reviewed. Following this, various defects that may contribute to the conductivity of CuSCN are discussed, and newly predicted phases characterized by layered 2-dimensional-like structures are highlighted. Finally, a summary of recent studies on the band-tail states and hole transport mechanisms in solution-deposited, polycrystalline CuSCN layers is presented.