Milani A, Barbieri V, Facibeni A, Russo V, Li Bassi A, Lucotti A, Tommasini M, Tzirakis M D, Diederich F, Casari C S
Micro and Nanostructured Materials Laboratory - NanoLab, Department of Energy, Politecnico di Milano via Ponzio 34/3, I-20133, Milano, Italy.
Department of Chemistry, Materials and Chem. Eng. 'G. Natta', Politecnico di Milano Piazza Leonardo da Vinci 32, I-20133, Milano, Italy.
Sci Rep. 2019 Feb 7;9(1):1648. doi: 10.1038/s41598-018-38367-9.
sp-Hybridized carbon atomic wires are appealing systems with large property tunability. In particular, their electronic properties are intimately related to length, structure, and type of functional end-groups as well as to other effects such as the intermolecular charge transfer with metal nanoparticles. Here, by a combined Raman, Surface Enhanced Raman Scattering (SERS) investigation and first principles calculations of different N,N-dimethylanilino-terminated polyynes, we suggest that, upon charge transfer interaction with silver nanoparticles, the function of sp-carbon atomic wire can change from electron donor to electron acceptor by increasing the wire length. In addition, the insertion into the wire of a strong electrophilic group (1,1,4,4-tetracyanobuta-1,3-diene-2,3-diyl) changes the electron-accepting molecular regions involved in this intermolecular charge transfer. Our results indicate that carbon atomic wires could display a tunable charge transfer between the sp-wire and the metal, and hold promise as active materials in organic optoelectronics and photovoltaics.
sp杂化的碳原子线是具有很大性质可调性的吸引人的体系。特别是，它们的电子性质与长度、结构、功能性端基的类型密切相关，也与其他效应有关，比如与金属纳米颗粒的分子间电荷转移。在这里，通过对不同的N，N-二甲基苯胺封端的聚炔进行拉曼光谱、表面增强拉曼散射（SERS）联合研究以及第一性原理计算，我们表明，在与银纳米颗粒发生电荷转移相互作用时，sp碳原子线的功能可以通过增加线的长度从电子供体转变为电子受体。此外，在碳链中插入一个强亲电基团（1,1,4,4-四氰基丁-1,3-二烯-2,3-二基）会改变这种分子间电荷转移中涉及的电子接受分子区域。我们的结果表明，碳原子线在sp线和金属之间可以表现出可调的电荷转移，并有望成为有机光电子学和光伏领域的活性材料。
