Probing Carrier Dynamics in sp${}^3$-Functionalized Single-Walled Carbon Nanotubes with Time-Resolved Terahertz Spectroscopy

Abstract

The controlled introduction of covalent sp${}^3$ defects into semiconducting single-walled carbon nanotubes (SWCNTs) gives rise to exciton localization and red-shifted near-infrared luminescence. The single-photon emission characteristics of these functionalized SWCNTs make them interesting candidates for electrically driven quantum light sources. However, the impact of sp${}^3$ defects on the carrier dynamics and charge transport in carbon nanotubes remains an open question. Here, we use ultrafast, time-resolved optical-pump terahertz-probe spectroscopy as a direct and quantitative technique to investigate the microscopic and temperature-dependent charge transport properties of pristine and functionalized (6,5) SWCNTs in dispersions and thin films. We find that sp${}^3$ functionalization increases charge carrier scattering, thus reducing the intra-nanotube carrier mobility. In combination with electrical measurements of SWCNT network field-effect transistors, these data enable us to distinguish between contributions of intra-nanotube band transport, sp${}^3$ defect scattering and inter-nanotube carrier hopping to the overall charge transport properties of nanotube networks.

ACS Nano 2022

References in corpus (6)

• Excitons versus electron-hole plasma in monolayer transition metal dichalcogenide semiconductors
• Luminescent Defects in Single-Walled Carbon Nanotubes for Applications
• Charge transport in semiconducting carbon nanotube networks
• Absolute Quantification of sp${}^3$ Defects in Semiconducting Single-Wall Carbon Nanotubes by Raman Spectroscopy
• Charge Transport in and Electroluminescence from sp${}^3$-Functionalized Carbon Nanotube Networks
• Transient terahertz spectroscopy of excitons and unbound carriers in quasi two-dimensional electron-hole gases

Cited by in corpus (3)

• Cove-edged Chiral Graphene Nanoribbons with Chirality-Dependent Bandgap and Carrier Mobility
• Ion-Exchange Doping of Semiconducting Single-Walled Carbon Nanotubes
• Tuning Electroluminescence from Functionalized SWCNT Networks further into the Near-Infrared