Exploring single-molecule wires with high conductance is of significant importance for constructing efficient molecular electronic devices. Contrary to the general method of increasing through-bond conjugation in conventional molecular wires, strengthening through-space conjugation is proposed herein to improve molecular conductance. A series of through-space conjugated molecular wires based on hexaphenylbenzene (HPB) are synthesized, and their crystal and electronic structures, conductance behaviors, and working mechanisms are investigated. The scanning tunneling microscopy-break junction technique discloses that, by replacing phenyls with thienyls in HPB, the molecular conductance is apparently boosted, with up to ∼239-fold enhancement, and becomes larger than that of the through-bond conjugated control molecule. The flicker noise analyses and theoretical calculation confirm that improved through-space conjugation with thienyls contributes significantly to high conductance. These findings demonstrate that the introduction of strong through-space conjugation is an effective and feasible approach to attain high molecular conductance.

探索具有高电导率的单分子导线对于构建高效的分子电子器件具有重要意义。与增加常规分子导线中的键合共轭的一般方法相反，本文提出了增强通孔共轭以改善分子电导。合成了一系列基于六苯基苯（HPB）的贯穿空间共轭分子线，并研究了它们的晶体和电子结构，电导行为以及工作机理。扫描隧道显微镜-断裂连接技术揭示，通过用HPB中的噻吩基取代苯基，分子电导率明显提高，最高可提高约239倍，并且比键合共轭控制分子大。闪烁噪声分析和理论计算证实，与噻吩基的改善的空间共轭性显着有助于高电导率。这些发现表明，引入强的空间共轭是获得高分子电导的有效且可行的方法。