Tian Yajie, Li Jieling, Wang Anhe, Shang Zhixin, Jian Honglei, Li Qi, Bai Shuo, Yan Xuehai
State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
Acta Biomater. 2022 Dec;154:135-144. doi: 10.1016/j.actbio.2022.09.073. Epub 2022 Oct 8.
Bio-endogenous peptide molecules are ideal components for fabrication of biocompatible and environmentally friendly semiconductors materials. However, to date, their applications have been limited due to the difficulty in obtaining stable, high-performance devices. Herein, simple amino acid derivatives fluorenylmethoxycarbonyl-leucine (Fmoc-L) and fluorenylmethoxycarbonyl-tryptophan (Fmoc-W) are utilized to form long-range ordered supramolecular nanostructures by tight aromatic stacking and extensive hydrogen bonding with mechanical, electrical and optical properties. For the first time, without addition of any photosensitizers, pure Fmoc-L microbelts and Fmoc-W microwires exhibit Young's modulus up to 28.79 and 26.96 GPa, and unprecedently high values of photocurrent responses up to 2.2 and 2.3 μA/cm, respectively. Meanwhile, Fmoc-W microwires with stable blue fluorescent emission under continuous excitation are successfully used as LED phosphors. Mechanism analysis shows that these two amino acids derivatives firstly formed dimers to reduce the bandgap, then further assemble into bioinspired semiconductor materials using the dimers as the building blocks. In this process, aromatic residues of amino acids are more conducive to the formation of semiconducting characteristics than fluorenyl groups. STATEMENT OF SIGNIFICANCE: Long-range ordered amino acid derivative assemblies with mechanical, electrical and optical properties were fabricated by a green and facile biomimetic strategy. These amino acid assemblies have Young's modulus comparable to that of concrete and exhibit typical semiconducting characteristics. Even without the addition of any photosensitizer, pure amino acid assemblies can still produce a strong photocurrent response and an unusually stable photoluminescence. The results suggest that amino acid structures with hydrophilic C-terminal and aromatic residues are more conducive to the formation of semiconducting characteristics. This work unlocks the potential for amino acid molecules to self-assemble into high-performance bioinspired semiconductors, providing a reference for customized development of biocompatible and environmentally friendly semiconductor materials through rational molecular design.
生物内源性肽分子是制造生物相容性和环境友好型半导体材料的理想成分。然而，迄今为止，由于难以获得稳定的高性能器件，它们的应用受到了限制。在此，利用简单的氨基酸衍生物芴甲氧羰基 - 亮氨酸（Fmoc-L）和芴甲氧羰基 - 色氨酸（Fmoc-W）通过紧密的芳香堆积和广泛的氢键作用形成具有机械、电学和光学性质的长程有序超分子纳米结构。首次在不添加任何光敏剂的情况下，纯Fmoc-L微带和Fmoc-W微丝的杨氏模量分别高达28.79和26.96 GPa，并且光电流响应值前所未有的高，分别高达2.2和2.3 μA/cm。同时，在连续激发下具有稳定蓝色荧光发射的Fmoc-W微丝成功用作发光二极管荧光粉。机理分析表明，这两种氨基酸衍生物首先形成二聚体以减小带隙，然后以二聚体为结构单元进一步组装成仿生半导体材料。在此过程中，氨基酸的芳香族残基比芴基更有利于形成半导体特性。重要性声明：通过绿色简便的仿生策略制备了具有机械、电学和光学性质的长程有序氨基酸衍生物组装体。这些氨基酸组装体的杨氏模量与混凝土相当，并表现出典型的半导体特性。即使不添加任何光敏剂，纯氨基酸组装体仍能产生强烈的光电流响应和异常稳定的光致发光。结果表明，具有亲水性C末端和芳香族残基的氨基酸结构更有利于形成半导体特性。这项工作开启了氨基酸分子自组装成高性能仿生半导体的潜力，为通过合理的分子设计定制开发生物相容性和环境友好型半导体材料提供了参考。
