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Metal–organic frameworks (MOFs), with diverse metal nodes and designable organic linkers, offer unique opportunities for the rational engineering of semiconducting properties. In this work, we report a mixed‐linker conductive MOF system with both tetrathiafulvalene and Ni‐bis(dithiolene) moieties, which allows the fine‐tuning of electronic structures and semiconductive characteristics. By continuously increasing the molar ratio between tetrathiafulvalene and Ni‐bis(dithiolene), the switching of the semiconducting behaviors from n‐type to p‐type was observed along with an increase in electrical conductivity by 3 orders of magnitude (from 2.88×10−7 S m−1 to 9.26×10−5 S m−1). Furthermore, mixed‐linker MOFs were applied for the chemiresistive detection of volatile organic compounds (VOCs), where the sensing performance was modulated by the corresponding linker ratios, showing synergistic and nonlinear modulation effects. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) constructed by tetrathiafulvalene-tetrabenzoate (H4TTFTB) have been widely studied in porous materials, while the studies of other TTFTB derivatives are rare. Herein, the meta derivative of the frequently used p-H4TTFTB ligand, m-H4TTFTB, and lanthanide (Ln) metal ions (Tb3+, Er3+, and Gd3+) were assembled into three novel MOFs. Compared with the reported porous Ln-TTFTB, the resulted three-dimensional frameworks, Ln-m-TTFTB ([Ln2(m-TTFTB)(m-H2TTFTB)0.5(HCOO)(DMF)]·2DMF·3H2O), possess a more dense stacking which leads to scarce porosity. The solid-state cyclic voltammetry studies revealed that these MOFs show similar redox activity with two reversible one-electron processes at 0.21 and 0.48 V (vs. Fc/Fc+). The results of magnetic properties suggested Dy-m-TTFTB and Er-m-TTFTB exhibit slow relaxation of the magnetization. Porosity was not found in these materials, which is probably due to the meta-configuration of the m-TTFTB ligand that seems to hinder the formation of pores. However, the m-TTFTB ligand has shown to be promising to construct redox-active or electrically conductive MOFs in future work. [ABSTRACT FROM AUTHOR]