Copper(I) thiocyanate (CuSCN) as a hole-transport material for large-area opto/electronics

Abstract

Recent advances in large-area optoelectronics research have demonstrated the tremendous potential of copper(I) thiocyanate (CuSCN) as a universal hole-transport interlayer material for numerous applications, including, transparent thin-film transistors, high-efficiency organic and hybrid organicinorganic photovoltaic cells, and organic light-emitting diodes (OLEDs). CuSCN combines intrinsic hole-transport (p-type) characteristics with a large bandgap (>3.5 eV) which facilitates optical transparency across the visible to near infrared part of the electromagnetic spectrum. Furthermore, CuSCN is readily available from commercial sources while it is inexpensive and can be processed at low-temperatures using solution-based techniques. This unique combination of desirable characteristics makes CuSCN a promising material for application in emerging large-area optoelectronics. In this review article, we outline some important properties of CuSCN and examine its use in the fabrication of potentially low-cost optoelectronic devices. The merits of using CuSCN in numerous emerging applications as an alternative to conventional hole-transport materials are also discussed.

Electronic Properties of Copper(I) Thiocyanate (CuSCN)

“…Wijeyasinghe and Anthopoulos [8] ); however, the studies on the hole transport properties of CuSCN are very limited. Pattanasattayavong et al, [1] employing field-effect measurements, q is the elementary electric charge) which were reported earlier for CuSCN by Mora-Seró et al [47] to be in the range of 0.001 to 0.01 cm 2 s -1 based on impedance spectroscopy measurements.…”

“…[7] Despite the breadth of the high potential technological applications (see also a review by Wijeyasinghe and Anthopoulos [8] on applications of CuSCN), the study into the electronic properties of CuSCN is still in the early stage. Some key aspects that provide the groundwork have recently been investigated both theoretically and experimentally, and it is the aim of this article to summarize these important works.…”

“…2017, 1600378 employed as a universal, highly transparent hole-injecting/extracting/transporting layer in a wide range of applications. [8] Additionally, CuSCN is chemically stable [13][14][15] and can be easily prepared at high purities as well as processed from solution-phase at low temperatures. [16][17][18][19] Moreover, owing to its quasi-molecular nature, CuSCN can be chemically modified; [20] in fact, the properties and applications of CuSCN derivatives are still awaiting exploration and could potentially open up a new range of possibilities.…”

Solution‐processed copper (I) thiocyanate (CuSCN) for highly efficient CdSe/CdTe thin‐film solar cells

“…Copper thiocyanate (CuSCN) is an inexpensive inorganic material with promising electronic property (eg, high work function~5.3 eV) and optical properties (eg, bandgap~3.6 eV), which has been investigated for several decades. 19,20 Recently, CuSCN as a promising and cost-effective hole transport layer for perovskite solar cells has achieved PCE~20% using a solution-processed procedure. 21 Meanwhile, CuSCN was also used for other dye-sensitized solar cells (DSSC), 22,23 such as chalcogenides Sb 2 S 3.…”

High‐Efficiency Fullerene Solar Cells Enabled by a Spontaneously Formed Mesostructured CuSCN‐Nanowire Heterointerface

“…Here, we show that the high‐efficiency solar cells can indeed be realized using two of the most commonly used fullerene derivatives, namely [6,6]‐phenyl‐C61‐butyric acid methyl ester (PC 60 BM), and [6,6]‐phenyl‐C71‐butyric acid methyl ester (PC 70 BM), as the light absorbing materials. Key to our success is the incorporation of the wide bandgap p‐type semiconductor copper thiocyanate (CuSCN), as the hole‐transporting, electron‐blocking material . In addition to its excellent and strictly unipolar transport properties, CuSCN is a superb hole‐transport layer (HTL) choice due to its low cost, toxicity, and annealing temperature, its chemical stability and its compatibility with a range of solution‐processing methods .…”