Details
| Original language | English |
|---|---|
| Article number | 064001 |
| Journal | Physical Review Materials |
| Volume | 4 |
| Issue number | 6 |
| Publication status | Published - Jun 2020 |
Abstract
Two-dimensional (2D) carbon nitrides compounds have attracted wide attention in recent years due to their diverse structures and excellent electronic, thermal, and optical properties. Here, by using first-principles approach, we investigate in details the stability, many-body effect, electronic/thermal transport properties, and thermoelectric performance of monolayer C7N6, as a new kind of 2D carbon nitride compounds composed of sp2-hybridized carbon atoms forming hexagonal lattice. Our results show that C7N6 monolayer is a direct band-gap semiconductor with a band-gap value of 3.56 eV under the accurate G0W0 method. Ab initio molecular dynamics simulations demonstrate that C7N6 maintains stable up to 1500K. Two exciton absorption peaks can be observed within the band gap with the respective large binding energies of 0.84 and 0.09eV, which means both excitons can exist at room temperature. Monolayer C7N6 possesses high carrier mobility with the order of 102-103cm2V-1s-1. Moreover, we find that the lattice thermal conductivity for C7N6 is as high as 134.55W/mK at room temperature, thus the thermoelectric figure of merit for C7N6 is relatively low. Our work suggests that C7N6 is a promising candidate for nanoscale (opto-)electronic and heat transport devices.
ASJC Scopus subject areas
- Materials Science(all)
- General Materials Science
- Physics and Astronomy(all)
- Physics and Astronomy (miscellaneous)
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In: Physical Review Materials, Vol. 4, No. 6, 064001, 06.2020.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Monolayer C7 N6
T2 - Room-temperature excitons with large binding energies and high thermal conductivities
AU - Wu, Yu
AU - Chen, Ying
AU - Ma, Congcong
AU - Lu, Zixuan
AU - Zhang, Hao
AU - Mortazavi, Bohayra
AU - Hou, Bowen
AU - Xu, Ke
AU - Mei, Haodong
AU - Rabczuk, Timon
AU - Zhu, Heyuan
AU - Fang, Zhilai
AU - Zhang, Rongjun
AU - Soukoulis, Costas M.
N1 - Funding information: This work is supported by the National Natural Science Foundation of China under Grant Nos. 11374063, 11674068 and 11544008, and Shanghai Municipal Natural Science Foundation under Grant Nos. 19ZR1402900 and 18ZR1402500. B. M. particularly appreciates funding by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany Excellence Strategy within the Cluster of Excellence PhoenixD (EXC 2122, Project ID 390833453).
PY - 2020/6
Y1 - 2020/6
N2 - Two-dimensional (2D) carbon nitrides compounds have attracted wide attention in recent years due to their diverse structures and excellent electronic, thermal, and optical properties. Here, by using first-principles approach, we investigate in details the stability, many-body effect, electronic/thermal transport properties, and thermoelectric performance of monolayer C7N6, as a new kind of 2D carbon nitride compounds composed of sp2-hybridized carbon atoms forming hexagonal lattice. Our results show that C7N6 monolayer is a direct band-gap semiconductor with a band-gap value of 3.56 eV under the accurate G0W0 method. Ab initio molecular dynamics simulations demonstrate that C7N6 maintains stable up to 1500K. Two exciton absorption peaks can be observed within the band gap with the respective large binding energies of 0.84 and 0.09eV, which means both excitons can exist at room temperature. Monolayer C7N6 possesses high carrier mobility with the order of 102-103cm2V-1s-1. Moreover, we find that the lattice thermal conductivity for C7N6 is as high as 134.55W/mK at room temperature, thus the thermoelectric figure of merit for C7N6 is relatively low. Our work suggests that C7N6 is a promising candidate for nanoscale (opto-)electronic and heat transport devices.
AB - Two-dimensional (2D) carbon nitrides compounds have attracted wide attention in recent years due to their diverse structures and excellent electronic, thermal, and optical properties. Here, by using first-principles approach, we investigate in details the stability, many-body effect, electronic/thermal transport properties, and thermoelectric performance of monolayer C7N6, as a new kind of 2D carbon nitride compounds composed of sp2-hybridized carbon atoms forming hexagonal lattice. Our results show that C7N6 monolayer is a direct band-gap semiconductor with a band-gap value of 3.56 eV under the accurate G0W0 method. Ab initio molecular dynamics simulations demonstrate that C7N6 maintains stable up to 1500K. Two exciton absorption peaks can be observed within the band gap with the respective large binding energies of 0.84 and 0.09eV, which means both excitons can exist at room temperature. Monolayer C7N6 possesses high carrier mobility with the order of 102-103cm2V-1s-1. Moreover, we find that the lattice thermal conductivity for C7N6 is as high as 134.55W/mK at room temperature, thus the thermoelectric figure of merit for C7N6 is relatively low. Our work suggests that C7N6 is a promising candidate for nanoscale (opto-)electronic and heat transport devices.
UR - http://www.scopus.com/inward/record.url?scp=85088391032&partnerID=8YFLogxK
U2 - 10.1103/PhysRevMaterials.4.064001
DO - 10.1103/PhysRevMaterials.4.064001
M3 - Article
AN - SCOPUS:85088391032
VL - 4
JO - Physical Review Materials
JF - Physical Review Materials
IS - 6
M1 - 064001
ER -