On-surface synthesis of singly and doubly porphyrin-capped graphene nanoribbon segments

In this record we provide data to support our recent findings on the synthesis of porphyrin-capped graphene nanoribbons. On-surface synthesis has emerged as a powerful tool for the construction of large, planar, π-conjugated structures that are not accessible through standard solution chemistry. Among such solid-supported architectures, graphene nanoribbons (GNRs) hold a prime position for their implementation in nanoelectronics due to their manifold outstanding properties. Moreover, using appropriately designed molecular precursors, this approach allows the synthesis of functionalized GNRs, leading to nanostructured hybrids with superior physicochemical properties. Among the potential “partners” for GNRs, porphyrins (Pors) outstand due to their rich chemistry, robustness, and electronic richness, among others. However, the use of such π-conjugated macrocycles for the construction of GNR hybrids is challenging and examples are scarce. In a recent publication we report singly and doubly Por-capped GNR segments presenting a commensurate and triply-fused GNR–Por heterojunction. The study of the electronic properties of such hybrid structures by high-resolution scanning tunneling microscopy, scanning tunneling spectroscopy, and DFT calculations reveals a weak hybridization of the electronic states of the GNR segment and the Por moieties despite their high degree of conjugation.

本数据集提供的数据用于支撑我们近期关于卟啉封端石墨烯纳米带（porphyrin-capped graphene nanoribbons）合成的研究发现。表面合成（on-surface synthesis）已成为构建大型平面π共轭结构的强大手段，这类结构无法通过标准溶液化学法获得。在这类固相支撑的架构中，石墨烯纳米带（graphene nanoribbons, GNRs）因其诸多优异特性，在纳米电子学领域的应用中占据核心地位。此外，通过合理设计的分子前驱体，该合成方法可制备功能化石墨烯纳米带（functionalized GNRs），进而得到具有优异理化性质的纳米结构杂化材料。在石墨烯纳米带的潜在“搭档”中，卟啉（porphyrins, Pors）凭借其丰富的化学性质、高稳定性以及优异的电子特性等优势脱颖而出。然而，利用这类π共轭大环化合物构建石墨烯纳米带杂化材料仍颇具挑战，相关报道较为稀少。在我们近期发表的一项研究中，报道了单卟啉封端和双卟啉封端的石墨烯纳米带片段，其具有匹配且三重融合的石墨烯纳米带-卟啉异质结。通过高分辨率扫描隧道显微镜（high-resolution scanning tunneling microscopy）、扫描隧道光谱（scanning tunneling spectroscopy）以及密度泛函理论（density functional theory, DFT）计算对这类杂化结构的电子性质进行研究后发现，尽管石墨烯纳米带片段与卟啉结构单元具有较高的共轭程度，二者的电子态却仅存在微弱的杂化作用。