| 1. |
- Liu, Heng, et al.
(author)
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Defect Management and Ion Infiltration Barrier Enable High-Performance Perovskite Solar Cells
- 2024
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In: ACS Energy Letters. - 2380-8195. ; 9:6, s. 2790-2799
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Journal article (peer-reviewed)abstract
- The stability of perovskite solar cells (PSCs) has been considered as one of the major obstacles toward practical application. Defects in the perovskite layer and ion infiltration from the hole transport layer (HTL) can trigger degradation of n-i-p PSCs. Herein, phenylhydrazine-4-sulfonic acid (PHPA) was employed as an additive to modulate perovskite crystallization during film formation, enlarging the perovskite crystal grain sizes to ∼3 μm. Density functional theory (DFT) calculations revealed that PHPA could effectively inhibit the formation of iodine vacancies (VI) and passivate the under-coordinated Pb2+ ions. Additionally, perfluorooctanoic acid (PFOA) was adopted to passivate the surface located dangling Pb2+ defects, improve the surface hydrophobicity, and inhibit Li+ ion migration from the HTL to the bottom perovskite, thus enhancing the device’s environmental and operational stability. Consequently, the resulting devices delivered a champion efficiency of 25.1% with an excellent maximum-power-point (MPP) tracking stability.
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| 2. |
- Wang, Zhe, et al.
(author)
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Moving model test of the smoke movement characteristics of an on-fire subway train running through a tunnel
- 2020
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In: Tunnelling and Underground Space Technology. - : Elsevier BV. - 0886-7798. ; 96
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Journal article (peer-reviewed)abstract
- A moving model test was carried out to investigate the associated smoke movement characteristics when a subway train on fire runs in a tunnel. Train models of the 1/10 and 1/15 scales were used. The spatial distributions of airflow velocity and smoke concentration were then analyzed, and the differences between moving fire sources and stationary fire sources were discussed. The results show that the smoke movement characteristics of a stationary fire source were greatly different from those of a moving one. Specifically, the smoke movement for the moving fire source was dominated by piston wind. Moreover, the process of the smoke spread could be divided into three stages, during which time the flow direction changed. The peak smoke concentration value occurred after the train tail passed by the measuring point. Besides, the impacts of train speed (60 km/h, 80 km/h, 100 km/h, and 120 km/h) and blockage ratio (0.19 and 0.43) on airflow velocity and smoke concentration were also investigated. With increasing train velocity, the airflow velocity increased, and the smoke concentration decreased. The maximum airflow velocity was approximately linear with the train velocity. Furthermore, the increasing blockage ratio enhanced the piston effect in the tunnel, thus increasing the airflow velocity and reducing the smoke concentration.
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