化学学报 ›› 2026, Vol. 84 ›› Issue (8): 1225-1230.DOI: 10.6023/A26060206 上一篇    下一篇

研究通讯

zyg拓扑的混合价态铜基金属有机骨架材料的合成、结构及性质

陈双双, 俞先引, 冯俊闯, 杨军, 卢治拥*(), 白俊峰*()   

  1. 南京工业大学化学与分子工程学院 化学与分子工程学院 南京 211816
  • 投稿日期:2026-06-18 发布日期:2026-08-10
  • 作者简介:

    “纪念兰州大学化学学科创建80周年”专辑

  • 基金资助:
    国家自然科学基金(22271150); 国家自然科学基金(22573048)

Syntheses, Structures, and Properties of Mixed-Valence Copper-Based Metal-Organic Frameworks with zyg Topology

Shuangshuang Chen, Xianyin Yu, Junchuang Feng, Jun Yang, Zhiyong Lu*(), Junfeng Bai*()   

  1. College of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, China
  • Received:2026-06-18 Published:2026-08-10
  • Contact: E-mail: zhiyong.lu@njtech.edu.cn; bjunfeng@njtech.edu.cn
  • About author:

    For the VSI “Celebration of 80th Anniversary of Chemistry in Lanzhou University”

  • Supported by:
    National Natural Science Foundation of China(22271150); National Natural Science Foundation of China(22573048)

混合价态金属有机骨架材料(MOFs)的可控构筑在配位化学中具有重要研究意义. 本工作以嘧啶-5-羧酸(HL)为有机配体, 在溶剂热条件下分别引入卤素离子CL-和Br-, 合成了两例具有相同zyg拓扑类型的混合价态铜基MOFs (12). 单晶X射线衍射分析表明, 12中Cu(I)与卤素阴离子(CL-/Br-)形成配位单元, 而Cu(II)以单核形式存在, 并通过配体连接形成三维骨架结构. 粉末X射线衍射结果进一步证实了它们具有高的结晶度和相纯度. 结合X射线光电子能谱、红外光谱及热重分析等表征手段, 对材料的价态分布及组成进行了验证. 这些MOFs都表现出全光谱吸收和良好的光电流响应, 表明其在光电催化和光传感方面具有应用潜力. 此外, Br-配位比CL-配位的MOFs具有更窄的带隙和更好的光电流响应.

关键词: 金属有机骨架材料, 同网络结构, 混合价铜, 卤素离子, 全光谱吸收

The controllable assembly of mixed-valence metal-organic frameworks (MOFs) remains a formidable challenge in coordination chemistry, primarily owing to the intricate balance required to stabilize disparate oxidation states within a single crystalline structure. In this study, we successfully synthesized two isoreticular copper-based mixed-valence MOFs under solvothermal conditions, employing pyrimidine-5-carboxylic acid (HL) as the bridging ligand and introducing chloride or bromide anions as coordinating modulators. The resulting MOFs, formulated as {(CuCl)2[CuⅠⅠ3(L)6(DMA)3](H2O)2}n (1) and {(CuBr)2[CuⅠⅠ3(L)6(DMA)3](H2O)2}n (2), were characterized by single-crystal X-ray diffraction, which revealed that both crystallize in the trigonal space group P3c1 and share an identical zyg-type three-dimensional network. These structures arise from the cooperative self-assembly of Cu(I)-halide secondary building units and mononuclear Cu(II) centers, which are interconnected via deprotonated pyrimidine-5-carboxylate linkers. Powder X-ray diffraction (PXRD) confirmed the high crystallinity and phase purity of the as-synthesized samples. Complementary characterization by X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), elemental analysis, verified the expected stoichiometry, the coexistence of Cu(I) and Cu(II), and thermal stability. Solvent immersion tests demonstrated that both frameworks retain their structural integrity upon exposure to common organic solvents, underscoring their good chemical stability. Ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS) revealed broad-spectrum responses with relatively narrow band gaps for both MOFs. Photoelectrochemical measurements, including transient photocurrent responses measurements and electrochemical impedance spectroscopy (EIS), indicated efficient photoinduced charge separation and interfacial charge migration. Notably, the bromide-coordinated analogue (2) exhibits a narrower band gap (1.22 eV vs 1.34 eV for 1), enhanced photocurrent density (1.06 μA•cm-2 vs 0.42 μA•cm-2 for 1), and reduced charge-transfer resistance relative to its chloride counterpart, clearly demonstrating that halide substitution effectively modulates the electronic band structure and promotes intramolecular electron transfer. Collectively, these mixed-valence Cu-MOFs exhibit full-spectrum absorption, robust photoelectrochemical activity, and good chemical stability, rendering them highly promising candidates for applications in photoelectrocatalysis and optical sensing.

Key words: metal-organic frameworks, isoreticular structures, mixed-valence copper, halide ions, full-spectrum absorption