Institute of Chemistry and ‡The Harvey M. Krueger Family Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem , Jerusalem 91904, Israel.
School of Electrical Engineering and ∥Tel Aviv University Center for Nanoscience and Nanotechnology, Tel Aviv University , Tel Aviv 69978, Israel.
Langmuir. 2017 Jun 6;33(22):5519-5526. doi: 10.1021/acs.langmuir.6b04599. Epub 2017 May 24.
Carbon nanotubes (CNTs) and semiconductor nanocrystals (SCNCs) are known to be interesting donor-acceptor partners due to their unique optical and electronic properties. These exciting features have led to the development of novel composites based on these two nanomaterials and to their characterization for use in various applications, such as components in sensors, transistors, solar cells and biomedical devices. Two approaches based on covalent and noncovalent methods have been suggested for coupling the SCNCs to CNTs. Most covalent conjugation methods used so far were found to disrupt the electronic structure of the CNTs or interfere with charge transfer in the CNT-SCNC interface. Moreover, it offers random and poorly organized nanoparticle coatings. Therefore, noncovalent methods are considered to be ideal for better electronic coupling. However, a key common drawback of noncovalent methods is the lack of stability which hampers their applicability. In this article, a method has been developed to couple semiconductor seeded nanorods onto CNTs through π-π interactions. The CNTs and pyrene conjugated SCNC hybrid materials were characterized by both microscopic and spectroscopic techniques. Fluorescence and photocurrent measurements suggest the proposed pi-stacking approach results in a strong electronic coupling between the CNTs and the SCNCs leading to better photocurrent efficiency than that of a covalent conjugation method reported using similar SCNC material. Overall, the CNT-SCNC films reported in the present study open the scope for the fabrication of optoelectronic devices for various applications.
碳纳米管 (CNTs) 和半导体纳米晶体 (SCNCs) 因其独特的光学和电子特性而被认为是有趣的供体-受体对。这些令人兴奋的特性导致了基于这两种纳米材料的新型复合材料的开发，并对其进行了表征，以用于各种应用，如传感器、晶体管、太阳能电池和生物医学设备中的组件。已经提出了两种基于共价和非共价方法的方法将 SCNCs 与 CNTs 偶联。迄今为止，大多数使用的共价偶联方法被发现会破坏 CNTs 的电子结构或干扰 CNT-SCNC 界面中的电荷转移。此外，它提供了随机且组织不良的纳米颗粒涂层。因此，非共价方法被认为是更好的电子偶联的理想方法。然而，非共价方法的一个关键共同缺点是缺乏稳定性，这限制了它们的适用性。在本文中，开发了一种通过π-π 相互作用将半导体种子纳米棒偶联到 CNTs 上的方法。通过微观和光谱技术对 CNT 和芘共轭 SCNC 杂化材料进行了表征。荧光和光电流测量表明，所提出的 π 堆积方法导致 CNT 和 SCNC 之间的强电子偶联，从而导致光电流效率优于使用类似 SCNC 材料报道的共价偶联方法。总体而言，本研究中报道的 CNT-SCNC 薄膜为各种应用的光电设备的制造开辟了前景。
