Remote-Contact Catalysis for Target-Diameter Semiconducting Carbon Nanotube Arrays

Wang, Jiangtao [Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States] (ORCID:0000000173234690); Zheng, Xudong [Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States]; Pitner, Gregory [Taiwan Semiconductor Manufacturing Company, Corporate Research, San Jose, California 95134, United States]; Ji, Xiang [Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States] (ORCID:0000000163051161); Zhang, Tianyi [Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States] (ORCID:0000000289983837); Yao, Aijia [Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States]; Zhu, Jiadi [Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States]; Palacios, Tomás [Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States] (ORCID:000000022190563X); Li, Lain-Jong [Taiwan Semiconductor Manufacturing Company, Corporate Research, Hsinchu 30075, Taiwan] (ORCID:0000000240597783); Wang, Han [Taiwan Semiconductor Manufacturing Company, Corporate Research, San Jose, California 95134, United States]; Kong, Jing [Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States] (ORCID:0000000305511208)

doi:10.1021/jacs.4c10592

DOE OSTI · 2859971

Remote-Contact Catalysis for Target-Diameter Semiconducting Carbon Nanotube Arrays

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Abstract

Electrostatic catalysis has been an exciting development in chemical synthesis (beyond enzymes catalysis1 ) in recent years, boosting reaction rates and selectively producing certain reaction products2 . Most of the studies to date have been focused on using external electric field (EEF) to rearrange the charge distribution in small molecule reactions such as Diels-Alder addition3 , carbene reaction4 , etc. However, in order for these EEFs to be effective, a field on the order of 1 V/nm (10 MV/cm) is required, and the direction of the EEF has to be aligned with the reaction axis5 . Such a large and oriented EEF will be challenging for large-scale implementation, or materials growth with multiple reaction axis or steps. Here, we demonstrate that the energy band at the tip of an individual single-walled carbon nanotube6 (SWCNT) can be spontaneously shifted in a high-permittivity growth environment, with its other end in contact with a low-work function electrode (e.g., hafnium carbide or titanium carbide7 ). By adjusting the Fermi level at a point where there is a substantial disparity in the density of states (DOS) between semiconducting (s-) and metallic (m-) SWCNTs8 , we achieve effective electrostatic catalysis for s-SWCNT growth assisted by a weak EEF perturbation (200V/cm). This approach enables the production of high-purity (99.92%) s-SWCNT horizontal arrays with narrow diameter distribution (0.95±0.04 nm), targeting the requirement of advanced SWCNT-based electronics for future computing9-11. These findings highlight the potential of electrostatic catalysis in precise materials growth, especially for s-SWCNTs, and pave the way for the development of advanced SWCNT-based electronics12.

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Wang, Jiangtao [Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States] (ORCID:0000000173234690), Zheng, Xudong [Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States], Pitner, Gregory [Taiwan Semiconductor Manufacturing Company, Corporate Research, San Jose, California 95134, United States], Ji, Xiang [Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States] (ORCID:0000000163051161), Zhang, Tianyi [Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States] (ORCID:0000000289983837), Yao, Aijia [Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States], Zhu, Jiadi [Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States], Palacios, Tomás [Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States] (ORCID:000000022190563X), Li, Lain-Jong [Taiwan Semiconductor Manufacturing Company, Corporate Research, Hsinchu 30075, Taiwan] (ORCID:0000000240597783), Wang, Han [Taiwan Semiconductor Manufacturing Company, Corporate Research, San Jose, California 95134, United States], Kong, Jing [Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States] (ORCID:0000000305511208). 2024-11-21. Remote-Contact Catalysis for Target-Diameter Semiconducting Carbon Nanotube Arrays. https://doi.org/10.1021/jacs.4c10592

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