Zhang Xiao, Graves Brian, De Volder Michael, Yang Wenming, Johnson Tyler, Wen Bo, Su Wei, Nishida Robert, Xie Sishen, Boies Adam
Department of Engineering, University of Cambridge, Cambridge CB2 1PZ, UK.
School of Mechanical Engineering, University of Science and Technology Beijing, Beijing 100083, China.
Sci Adv. 2020 Sep 30;6(40). doi: 10.1126/sciadv.abb6010. Print 2020 Sep.
The direct growth of single-walled carbon nanotubes (SWCNTs) with narrow chiral distribution remains elusive despite substantial benefits in properties and applications. Nanoparticle catalysts are vital for SWCNT and more generally nanomaterial synthesis, but understanding their effect is limited. Solid catalysts show promise in achieving chirality-controlled growth, but poor size control and synthesis efficiency hampers advancement. Here, we demonstrate the first synthesis of refractory metal nanoparticles (W, Mo, and Re) with near-monodisperse sizes. High concentrations ( = 10 to 10 cm) of nanoparticles (diameter 1 to 5 nm) are produced and reduced in a single process, enabling SWCNT synthesis with controlled chiral angles of 19° ± 5°, demonstrating abundance >93%. These results confirm the interface thermodynamics and kinetic growth theory mechanism, which has been extended here to include temporal dependence of fast-growing chiralities. The solid catalysts are further shown effective via floating catalyst growth, offering efficient production possibilities.
尽管单壁碳纳米管（SWCNTs）在性能和应用方面具有诸多优势，但其窄手性分布的直接生长仍难以实现。纳米颗粒催化剂对于SWCNT以及更广泛的纳米材料合成至关重要，但对其作用的理解有限。固体催化剂在实现手性控制生长方面显示出前景，但尺寸控制不佳和合成效率低下阻碍了进展。在此，我们展示了首次合成尺寸近乎单分散的难熔金属纳米颗粒（W、Mo和Re）。在单一过程中产生并还原了高浓度（=10至10厘米）的纳米颗粒（直径1至5纳米），从而能够合成手性角为19°±5°且丰度>93%的可控SWCNT。这些结果证实了界面热力学和动力学生长理论机制，在此已将其扩展以包括快速生长手性的时间依赖性。通过浮动催化剂生长进一步表明固体催化剂是有效的，提供了高效生产的可能性。
