TY - JOUR
T1 - Photoluminescent Semiconducting Graphene Nanoribbons via Longitudinally Unzipping of Single-Walled Carbon Nanotubes
AU - Li, Hu
AU - Zhang, Jiawei
AU - Gholizadeh, A. Baset
AU - Brownless, Joseph
AU - Fu, Yangming
AU - Cai, Wensi
AU - Han, Yuanyuan
AU - Duan, Tianbo
AU - Wang, Yiming
AU - Ling, Haotian
AU - Leifer, Klaus
AU - Curry, Richard
AU - Song, Aimin
N1 - Funding Information:
We are grateful to M. Mcgowan, Dr. L. Zhang, Dr. C. Holroyd, Dr. T. Bointon, and Dr. R. Raffaello for the technical support. This work was made possible with the generous support of Louis and Amy Wong through the Louis Wong Hak Wood Presidential Scholarship. We also acknowledge the UK EPSRC (EP/M015513/2 and EP/N20057/2), Swedish Research Council Formas (2019-01538), STINT (IB2020-8594), Aforsk (20-280), Olle Engkvist (211-0068), I Bergh Scholarship, Qilu young scholar program of Shandong University, National Key Research and Development Program of China (2016YFA0301200), and National Natural Science Foundation of China (62074094) for the financial support.
Publisher Copyright:
© 2021 American Chemical Society.
PY - 2021/10/30
Y1 - 2021/10/30
N2 - The lack of a sizeable bandgap has so far prevented graphene from building effective electronic and optoelectronic devices despite its numerous exceptional properties. Intensive theoretical research reveals that a bandgap larger than 1 eV can only be achieved in sub-3 nm wide graphene nanoribbons (GNRs), but real fabrication of such ultra-narrow GNRs still remains a critical challenge. Herein, we demonstrate an approach for the synthesis of ultranarrow and photoluminescent semiconducting GNRs by longitudinally unzipping single-walled carbon nanotubes. Atomic force microscopy reveals the unzipping process and the resulting 2.2 nm wide GNRs are found to emit strong and sharp photoluminescence at ~685 nm, demonstrating a very desirable semiconducting nature. This bandgap of 1.8 eV is further confirmed by follow-up photoconductivity measurements, where a considerable photocurrent is generated as the excitation wavelength becomes shorter than 700 nm. More importantly, our fabricated GNR field-effect transistors (FETs), by employing the hexagonal boron nitride encapsulated heterostructure to achieve edge-bonded contacts, demonstrate a high current on/off ratios beyond 105, and carrier mobility of 840 cm2/Vs, approaching the theoretical scattering limit in semiconducting GNRs at room temperature. Especially, highly aligned GNR bundles with lengths up to a millimeter are also achieved by prepatterning a template, and the fabricated GNR bundle FETs show a high on/off ratio reaching 105, well-defined saturation currents and strong light-emitting properties. Therefore, GNRs produced by this method opens a door for promising applications in graphene-based electronics and optoelectronics.
AB - The lack of a sizeable bandgap has so far prevented graphene from building effective electronic and optoelectronic devices despite its numerous exceptional properties. Intensive theoretical research reveals that a bandgap larger than 1 eV can only be achieved in sub-3 nm wide graphene nanoribbons (GNRs), but real fabrication of such ultra-narrow GNRs still remains a critical challenge. Herein, we demonstrate an approach for the synthesis of ultranarrow and photoluminescent semiconducting GNRs by longitudinally unzipping single-walled carbon nanotubes. Atomic force microscopy reveals the unzipping process and the resulting 2.2 nm wide GNRs are found to emit strong and sharp photoluminescence at ~685 nm, demonstrating a very desirable semiconducting nature. This bandgap of 1.8 eV is further confirmed by follow-up photoconductivity measurements, where a considerable photocurrent is generated as the excitation wavelength becomes shorter than 700 nm. More importantly, our fabricated GNR field-effect transistors (FETs), by employing the hexagonal boron nitride encapsulated heterostructure to achieve edge-bonded contacts, demonstrate a high current on/off ratios beyond 105, and carrier mobility of 840 cm2/Vs, approaching the theoretical scattering limit in semiconducting GNRs at room temperature. Especially, highly aligned GNR bundles with lengths up to a millimeter are also achieved by prepatterning a template, and the fabricated GNR bundle FETs show a high on/off ratio reaching 105, well-defined saturation currents and strong light-emitting properties. Therefore, GNRs produced by this method opens a door for promising applications in graphene-based electronics and optoelectronics.
KW - high mobility
KW - high on-off ratio
KW - longitudinal unzipping
KW - photoluminescence
KW - semiconducting graphene nanoribbons
U2 - 10.1021/acsami.1c14597
DO - 10.1021/acsami.1c14597
M3 - Article
AN - SCOPUS:85118981916
VL - 13
SP - 52892
EP - 52900
JO - ACS Applied Materials and Interfaces
JF - ACS Applied Materials and Interfaces
SN - 1944-8244
IS - 44
ER -