| 1. |
- Gao, Lingfeng, et al.
(författare)
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Applications of Few-Layer Nb2C MXene : Narrow-Band Photodetectors and Femtosecond Mode-Locked Fiber Lasers
- 2021
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Ingår i: ACS Nano. - : American Chemical Society (ACS). - 1936-0851 .- 1936-086X. ; 15:1, s. 954-965
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Tidskriftsartikel (refereegranskat)abstract
- Although the physicochemical properties of niobium carbide (Nb2C) have been widely investigated, their exploration in the field of photoelectronics is still at the infancy stage with many potential applications that remain to be exploited. Hence, it is demonstrated here that few-layer Nb2C MXene can serve as an excellent building block for both photoelectrochemical-type photodetectors (PDs) and mode-lockers. We show that the photoresponse performance can be readily adjusted by external conditions and that Nb2C NSs exhibit a great potential for narrow-band PDs. The demonstrated mechanism was further confirmed by work functions predicted by density functional theory calculations. In addition, as an optical switch for passively mode-locked fiber lasers, ultrastable pulses can be demonstrated in the telecommunication and mid-infrared regions for Nb2C MXene, and as high as the 69th harmonic order with 411 MHz at the center wavelength of 1882 nm can be achieved. These intriguing results indicate that few-layer Nb2C nanosheets can be used as building blocks for various photoelectronic devices, further broadening the application prospects of two-dimensional MXenes.
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| 2. |
- Jing, Xiao, et al.
(författare)
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Safety benefit of cooperative control for heterogeneous traffic on-ramp merging
- 2022
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Ingår i: Transportation Safety and Environment. - : Oxford University Press (OUP). - 2631-6765 .- 2631-4428. ; 4:4
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Tidskriftsartikel (refereegranskat)abstract
- The safety of heterogeneous traffic is a vital topic in the oncoming era of autonomous vehicles (AVs). The cooperative vehicle infrastructure system (CVIS) is considered to improve heterogeneous traffic safety by connecting and controlling AVs cooperatively, and the connected AVs are so-called connected and automated vehicles (CAVs). However, the safety impact of cooperative control strategy on the heterogeneous traffic with CAVs and human-driving vehicles (HVs) has not been well investigated. In this paper, based on the traffic simulator SUMO, we designed a typical highway scenario of on-ramp merging and adopted a cooperative control method for CAVs. We then compared the safety performance for two different heterogeneous traffic systems, i.e. AV and HV, CAV and HV, respectively, to illustrate the safety benefits of the cooperative control strategy. We found that the safety performance of the CAV and HV traffic system does not always outperform that of AV and HV. With random departSpeed and higher arrival rate, the proposed cooperative control method would decrease the conflicts significantly whereas the penetration rate is over 80%. We further investigated the conflicts in terms of the leading and following vehicle types, and found that the risk of a AV/CAV followed by a HV is twice that of a HV followed by another HV. We also considered the safety effect of communication failure, and found that there is no significant impact until the packet loss probability is greater than 30%, while communication delay's impact on safety can be ignored according to our experiments.
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| 3. |
- Zhang, Ye, et al.
(författare)
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Application of graphdiyne oxide in photoelectrochemical-type photodetectors and ultrafast fiber lasers
- 2022
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Ingår i: Nano Today. - : Elsevier. - 1748-0132 .- 1878-044X. ; 47
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Tidskriftsartikel (refereegranskat)abstract
- Graphdiyne oxide (GDYO), the oxidized form of graphdiyne (GDY), has been widely explored for applica-tions in various technological fields owing to its fascinating properties. However, the research of GDYO for applications in photodetectors (PDs) and mode-locker has been lagging. Herein, we present experimental demonstrations of promising applications of GDYO for narrow-band photoelectrochemical (PEC)-type PDs with tunable performance. Moreover, the measured excellent nonlinear optical absorption of GDYO makes it a suitable material for mode-locking in ultrafast fiber lasers. Ultrastable pulses as short as 1.5 ps could be obtained from an Erbium-doped fiber laser based on GDYO at 1559 nm. These findings have been supported and interpreted by density functional theory (DFT) calculations as well as transient absorption dynamics studies. The presented results provide pathways for the future utilization of GDYO in high-performance optoelectronic devices.
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| 4. |
- Zhang, Ye, et al.
(författare)
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Black Phosphorus/Polymers : Status and Challenges
- 2021
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Ingår i: Advanced Materials. - : John Wiley & Sons. - 0935-9648 .- 1521-4095. ; 33:37
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Forskningsöversikt (refereegranskat)abstract
- As a newly emerged mono-elemental nanomaterial, black phosphorus (BP) has been widely investigated for its fascinating physical properties, including layer-dependent tunable band gap (0.3-1.5 eV), high ON/OFF ratio (10(4)), high carrier mobility (10(3) cm(2) V-1 s(-1)), excellent mechanical resistance, as well as special in-plane anisotropic optical, thermal, and vibrational characteristics. However, the instability caused by chemical degradation of its surface has posed a severe challenge for its further applications. A focused BP/polymer strategy has more recently been developed and implemented to hurdle this issue, so at present BP/polymers have been developed that exhibit enhanced stability, as well as outstanding optical, thermal, mechanical, and electrical properties. This has promoted researchers to further explore the potential applications of black phosphorous. In this review, the preparation processes and the key properties of BP/polymers are reviewed, followed by a detailed account of their diversified applications, including areas like optoelectronics, bio-medicine, and energy storage. Finally, in accordance with the current progress, the prospective challenges and future directions are highlighted and discussed.
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