Epitaxial Electrodeposition of Hole Transport CuSCN Nanorods on Au(111) at the Wafer Scale and Lift-Off to Produce Flexible and Transparent Foils
Abstract
The wide bandgap p-type metal pseudohalide semiconductor copper(I) thiocyanate (CuSCN) can serve as a transparent hole transport layer in various opto-electronic applications such as perovsksite and organic solar cells and light-emitting diodes. The material deposits as one-dimensional CuSCN nanorod arrays, which are advantageous due to their high surface area and good charge transport properties. However, the growth of high-quality epitaxial CuSCN nanorods has remained a challenge. Here, we introduce a low cost and highly scalable room temperature procedure for producing epitaxial CuSCN nanorods on Au(111) by an electrochemical method. Epitaxial CuSCN grows on Au(111) with a high degree of in-plane as well as out-of-plane order with +0.22% coincidence site lattice mismatch. The phase of CuSCN that deposits is a function of the Cu2+/SCN- ratio in the deposition bath. A pure rhombohedral material deposits at higher SCN- concentrations, whereas a mixture of rhombohedral and hexagonal phases deposits at lower SCN- concentrations. A Au/epitaxial CuSCN/Ag diode has a diode quality factor of 1.4, whereas a diode produced with polycrystalline CuSCN has a diode quality factor of 2.1. A highly ordered foil of CuSCN was produced by epitaxial lift-off following a triiodide etch of the thin Au substrate. The 400 nm-thick CuSCN foil had an average 94% transmittance in the visible range and a 3.85 eV direct bandgap.
Recommended Citation
B. Luo et al., "Epitaxial Electrodeposition of Hole Transport CuSCN Nanorods on Au(111) at the Wafer Scale and Lift-Off to Produce Flexible and Transparent Foils," Chemistry of Materials, vol. 34, no. 3, pp. 970 - 978, American Chemical Society (ACS), Jan 2022.
The definitive version is available at https://doi.org/10.1021/acs.chemmater.1c02694
Department(s)
Chemistry
International Standard Serial Number (ISSN)
1520-5002; 0897-4756
Document Type
Article - Journal
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 2022 American Chemical Society (ACS), All rights reserved.
Publication Date
18 Jan 2022
Comments
This material is based on work supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering, under grant no. DE-FG02-08ER46518.