He Zhiyan, Wang Kai, Yan Chao, Wan Lijuan, Zhou Qingping, Zhang Teng, Ye Xiaowo, Zhang Yanming, Shi Fangyuan, Jiang Shenghao, Zhao Jian, Wang Kunchan, Chen Changxin
National Key Laboratory of Science and Technology on Micro/Nano Fabrication, Key Laboratory for Thin Film and Microfabrication of the Ministry of Education, Department of Micro/Nano Electronics, School of Electronic Information and Electrical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
School of Materials Science and Engineering, Jiangsu University of Science and Technology, Zhenjiang 212001, China.
ACS Appl Mater Interfaces. 2023 Feb 8;15(5):7148-7156. doi: 10.1021/acsami.2c21220. Epub 2023 Jan 24.
Narrow graphene nanoribbons (GNRs) and GNR/single-walled carbon nanotube (SWNT) intramolecular heterojunctions are ideal candidates to construct next-generation electronic and optoelectronic devices. However, the fabrication of high-quality long sub-5 nm wide GNRs and GNR/SWNT heterojunctions is a great challenge. Here, we report a method to produce high-quality sub-5 nm wide GNRs with smooth edges and GNR/SWNT intramolecular heterostructures via palladium-catalyzed full and partial unzipping of SWNTs, respectively. The resulting GNRs could be as narrow as 2.2 nm and had an average length of over 1 μm. By adjusting the unzipping time and the deposited positions of palladium nanoparticles, controlled multiple GNR/SWNT heterostructures were also fabricated on an individual parent SWNT. A GNR field-effect transistor (FET) constructed by a 3.1 nm wide GNR could simultaneously achieve a high on/off current ratio of 1.1 × 10 and a large mobility of 598 cm V s. The photovoltaic device based on a single GNR (2.4 nm in width)/SWNT (0.8 nm in diameter) heterojunction exhibited a large open-circuit voltage () of 0.52 V and a high external power conversion efficiency (η) of 4.7% under the 1550 nm wavelength illumination of 931 mW cm. Our method provides a pathway to controllably prepare high-quality sub-5 nm GNRs and GNR/SWNT heterojunctions for fundamental studies and practical applications in the electronic and optoelectronic fields.
窄石墨烯纳米带（GNRs）和GNR/单壁碳纳米管（SWNT）分子内异质结是构建下一代电子和光电器件的理想候选材料。然而，高质量的亚5纳米宽GNRs和GNR/SWNT异质结的制备是一个巨大的挑战。在此，我们报告了一种分别通过钯催化单壁碳纳米管的完全和部分解链来制备具有光滑边缘的高质量亚5纳米宽GNRs和GNR/SWNT分子内异质结构的方法。所得的GNRs可以窄至2.2纳米，平均长度超过1微米。通过调整解链时间和钯纳米颗粒的沉积位置，还在单个母单壁碳纳米管上制备了可控的多个GNR/SWNT异质结构。由3.1纳米宽的GNR构建的GNR场效应晶体管（FET）可以同时实现1.1×10的高开/关电流比和598厘米²伏⁻¹秒⁻¹的大迁移率。基于单个GNR（宽度为2.4纳米）/SWNT（直径为0.8纳米）异质结的光伏器件在931毫瓦厘米⁻²的1550纳米波长光照下表现出0.52伏的大开路电压（Voc）和4.7%的高外部功率转换效率（η）。我们的方法为在电子和光电子领域的基础研究和实际应用中可控地制备高质量的亚5纳米GNRs和GNR/SWNT异质结提供了一条途径。
