Du Zhipeng, Chen Xu, Liu Wei, Wang Han, Xu Qianting, Shang Xiaoying, Song Yipeng, Chen Xueyuan, Luo Junhua, Zhao Sangen
State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China.
Fujian College, University of Chinese Academy of Sciences, Fuzhou 350002, China.
Natl Sci Rev. 2024 Oct 21;12(1):nwae370. doi: 10.1093/nsr/nwae370. eCollection 2025 Jan.
Two-dimensional (2D) van der Waals (vdW) materials are known for their intriguing physical properties, but their rational design and synthesis remain a great challenge for chemists. In this work, we successfully synthesized a new non-centrosymmetric oxide, i.e. InSbMoO, with Sb lone-pair electrons serving as chemical scissor to generate its 2D vdW crystal structure. Monolayer and few-layer InSbMoO flakes are readily obtained via facile mechanical exfoliation. They exhibit strong second-harmonic generation (SHG) response with an effective second-order nonlinear optical susceptibility [Formula: see text]of 32.4 pm·V. Meanwhile, the SHG response is in-plane anisotropic and directly proportional to the layer thickness, independent of layer parity. In addition, the InSbMoO flakes exhibit excellent thermal and atmospheric stability, along with pronounced anisotropy in Raman spectroscopy. This work implies that using lone-pair electrons as chemical scissor is an effective strategy for designing and synthesizing new 2D vdW materials for integrated photonic applications.
二维（2D）范德华（vdW）材料以其引人入胜的物理性质而闻名，但其合理设计与合成对化学家而言仍是巨大挑战。在本工作中，我们成功合成了一种新的非中心对称氧化物，即InSbMoO，其中Sb孤对电子充当化学剪刀以生成其二维范德华晶体结构。通过简便的机械剥离很容易获得单层和少层InSbMoO薄片。它们表现出强烈的二次谐波产生（SHG）响应，有效二阶非线性光学极化率[公式：见正文]为32.4皮米·伏。同时，SHG响应在面内是各向异性的，且与层厚度成正比，与层数奇偶性无关。此外，InSbMoO薄片表现出优异的热稳定性和大气稳定性，以及拉曼光谱中明显的各向异性。这项工作表明，使用孤对电子作为化学剪刀是设计和合成用于集成光子应用的新型二维范德华材料的有效策略。
