Zhang Weiguang, Yang Tong, Jiang Shuo, Ding Fang, Liu Yong, Wang Mengxu, Li Wenqi, Feng Jing, Deng Mengjie, Yang Sufang, Zhai Yaxin, Wang Jian-Bo, Chen Bo, Ma Ming, Zhang Wei
Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education), Key Laboratory of Phytochemical R&D of Hunan Province, Key Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan Province, Institute of Interdisciplinary Studies, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha, 410081, China.
Department of Physics, Hunan Normal University, Changsha, 410081, China.
Small. 2025 Aug;21(32):e2412215. doi: 10.1002/smll.202412215. Epub 2025 Jun 16.
Chiral materials, which can manipulate the electron spin by the chiral-induced spin selectivity (CISS) effect without involving the complicated magnetic components, exhibits great potentials in low-cost spin optoelectronics. However, ideal CISS usually requires a relatively ordered and conductive (or insulated but ultrathin) chiral layer, which contradicts the disordered-packing and high-impedance characteristics of chiral molecules, preventing the direct application of most chiral molecules for CISS and increasing the difficulty to prepare chiral spin-selective layers. Here, a general disordered and conductive chiral molecular strategy is proposed to simply construct the small-molecule-based spin polarizer. Directly spin-coating chiral molecules onto the electrode forms the disordered chiral thin film, which exhibits obvious CISS effects demonstrated by an electrochemical oxygen evolution reaction (OER) and a magnetic conductive probe-atomic force microscopy (mcp-AFM). More importantly, by disorderly doping conductive graphite nanoparticles into this film, the high impedance of the chiral molecular layers can be effectively reduced, which results in a higher OER activity with lower HO byproduct and a stronger spin-polarization degree. This can be attributed to a conductivity-enhanced disordered CISS effect, which may lay the foundation for designing universal and high-performance spintronic devices.
手性材料可通过手性诱导自旋选择性（CISS）效应操纵电子自旋，而无需复杂的磁性组件，在低成本自旋光电器件中展现出巨大潜力。然而，理想的CISS通常需要相对有序且导电（或绝缘但超薄）的手性层，这与手性分子的无序堆积和高阻抗特性相矛盾，阻碍了大多数手性分子直接用于CISS，也增加了制备手性自旋选择层的难度。在此，提出了一种通用的无序且导电的手性分子策略，以简便地构建基于小分子的自旋偏振器。将手性分子直接旋涂在电极上形成无序的手性薄膜，通过电化学析氧反应（OER）和磁导电探针原子力显微镜（mcp-AFM）证明其具有明显的CISS效应。更重要的是，通过将导电石墨纳米颗粒无序掺杂到该薄膜中，可有效降低手性分子层的高阻抗，从而在产生较少HO副产物的情况下实现更高的OER活性以及更强的自旋极化程度。这可归因于电导率增强的无序CISS效应，这可能为设计通用且高性能的自旋电子器件奠定基础。
