Chen Shunwei, Jiang Yuhang, Jia Shangke, Liu Hao, Zhang Guangwei, Han Xiujun, Zhang Ruiqin
School of Materials Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, China.
Department of Physics, City University of Hong Kong, Kowloon, Hong Kong SAR, China.
Phys Chem Chem Phys. 2021 Nov 3;23(42):24239-24248. doi: 10.1039/d1cp03932f.
Single-walled carbon nanotubes (SWCNTs) have evoked great interest for various luminescent applications, but the large emission heterogeneity resulting from the structural complexity of the samples seriously restricts their further development. Herein we theoretically explore the electronic structures and optical properties of phenine nanotubes (pNTs), which are typical luminescent SWCNT derivatives with determined molecular structures that have been synthesized recently (Z. Sun, K. Ikemoto, T. M. Fukunaga, T. Koretsune, R. Arita, S. Sato and H. Isobe, , 2019, , 151-155; K. Ikemoto, S. Yang, H. Naito, M. Kotani, S. Sato and H. Isobe, , 2020, , 1807). Interestingly, pNTs are found to feature different semiconducting properties to SWCNTs, as indicated by a spatial separation trend in the HOMO and LUMO resulting from periodic structural vacancies. The HOMO-LUMO and optical gaps of pNTs depend inversely on their lengths and diameters, but diameter variation should be an ineffective method for property tuning due to its negligible influence. By contrast, chemical modifications N doping or hydrogenation highly affect the HOMO-LUMO gaps and their distributions and greatly broaden the light absorption/emission range, and importantly, low-dose hydrogenation is predicted to be a feasible strategy to enhance luminescence. This work, by studying the fundamental photophysical properties of pNTs and making comparisons to SWCNTs, shows the promise of structural vacancy engineering and surface functionalization in acquiring multifunctional tube-like materials.
单壁碳纳米管（SWCNTs）在各种发光应用中引起了极大的兴趣，但由于样品结构复杂性导致的大发射异质性严重限制了它们的进一步发展。在此，我们从理论上探索了菲纳米管（pNTs）的电子结构和光学性质，pNTs是典型的发光SWCNT衍生物，具有确定的分子结构，最近已被合成（Z. Sun，K. Ikemoto，T. M. Fukunaga，T. Koretsune，R. Arita，S. Sato和H. Isobe，，2019，，151 - 155；K. Ikemoto，S. Yang，H. Naito，M. Kotani，S. Sato和H. Isobe，，2020，，1807）。有趣的是，发现pNTs具有与SWCNTs不同的半导体性质，这由周期性结构空位导致的HOMO和LUMO中的空间分离趋势所表明。pNTs的HOMO - LUMO和光学带隙与其长度和直径成反比，但由于直径变化的影响可忽略不计，因此它应该是一种无效的性质调节方法。相比之下，化学修饰（N掺杂或氢化）对HOMO - LUMO带隙及其分布有很大影响，并大大拓宽了光吸收/发射范围，重要的是，低剂量氢化预计是增强发光的可行策略。这项工作通过研究pNTs的基本光物理性质并与SWCNTs进行比较，展示了结构空位工程和表面功能化在获得多功能管状材料方面的前景。
