Chiral Van Der Waals Superlattices for Enhanced Spin-Selective Transport And Spin-Dependent Electrocatalytic Performance.
Zhiyun BianYuki NakanoKeisuke MiyataIchiro OyaMasaki NobuokaYusuke TsutsuiShu SekiMasayuki SudaPublished in: Advanced materials (Deerfield Beach, Fla.) (2023)
The emergence of chiral-induced spin-selectivity (CISS) effect offers a new avenue for chiral organic molecules to autonomously manipulate spin configurations, thereby opening up possibilities in spintronics and spin-dependent electrochemical applications. Despite extensive exploration of various chiral systems as spin filters, one often encounters challenges in achieving simultaneously high conductivity and high spin polarization (SP). In this study, a promising chiral van der Waals superlattice, specifically the chiral TiS 2 crystal, was synthesized via electrochemical intercalation of chiral molecules into a metallic TiS 2 single crystal. Multiple tunneling processes within the highly ordered chiral layered structure of chiral TiS 2 superlattices results in an exceptionally high SP exceeding 90%. This remarkable observation of significantly high SP within the linear transport regime is unprecedented. Furthermore, the chiral TiS 2 electrode exhibited enhanced catalytic activity for oxygen evolution reaction (OER) due to its remarkable spin-selectivity for triplet oxygen evolution. The OER performance of chiral TiS 2 superlattice crystals presented here exhibits superior characteristics to previously reported chiral MoS 2 catalysts, with an approximately 10-fold increase in current density. The combination of metallic conductivity and high SP sets the stage for the development of a new generation of CISS materials, enabling a wide range of electron spin-based applications. This article is protected by copyright. All rights reserved.