The ability to generate stable and coherent short wavelength radiation is a great promise of the externally seeded free-electron laser. However, the fre- quency up-conversion efficiency is limited to a small number in...The ability to generate stable and coherent short wavelength radiation is a great promise of the externally seeded free-electron laser. However, the fre- quency up-conversion efficiency is limited to a small number in a single stage setup. In this paper, we propose a new scheme to produce coherent hard X-ray FEL with two- beam based two-stage echo-enabled harmonic generation configuration. Electron beams with quite different proper- ties are separately used in each stage and a monochromator is adopted to purify the radiation from first stage for seeding the second stage. Three-dimensional start-to-end simulations have been performed with realistic parameters to show the feasibility of the proposed scheme.展开更多
Perovskite solar cells(PSCs)commonly exhibit significant performance degradation due to ion migration through the top charge transport layer and ultimately metal electrode corrosion.Here,we demonstrate an interfacial ...Perovskite solar cells(PSCs)commonly exhibit significant performance degradation due to ion migration through the top charge transport layer and ultimately metal electrode corrosion.Here,we demonstrate an interfacial management strategy using a boron chloride subphthalocyanine(Cl_(6)SubPc)/fullerene electron-transport layer,which not only passivates the interfacial defects in the perovskite,but also suppresses halide diffusion as evidenced by multiple techniques,including visual element mapping by electron energy loss spectroscopy.As a result,we obtain inverted PSCs with an efficiency of 22.0%(21.3%certified),shelf life of 7000 h,T_(80) of 816 h under damp heat stress(compared to less than 20 h without Cl_(6)SubPc),and initial performance retention of 98%after 2000 h at 80℃in inert environment,90%after 2034 h of illumination and maximum power point tracking in ambient for encapsulated devices and 95%after 1272 h outdoor testing ISOS-O-1.Our strategy and results pave a new way to move PSCs forward to their potential commercialization solidly.展开更多
基金supported by the National Development and Reform Commission([2013]2347)National Natural Science Foundation of China(11475250)the Shanghai Natural Science Foundation(13ZR1464700)
文摘The ability to generate stable and coherent short wavelength radiation is a great promise of the externally seeded free-electron laser. However, the fre- quency up-conversion efficiency is limited to a small number in a single stage setup. In this paper, we propose a new scheme to produce coherent hard X-ray FEL with two- beam based two-stage echo-enabled harmonic generation configuration. Electron beams with quite different proper- ties are separately used in each stage and a monochromator is adopted to purify the radiation from first stage for seeding the second stage. Three-dimensional start-to-end simulations have been performed with realistic parameters to show the feasibility of the proposed scheme.
基金supported by the National Natural Science Foundation of China (61775091, and U2001216)the Shenzhen Key Laboratory Project (ZDSYS201602261933302)+2 种基金Natural Science Foundation of Shenzhen Innovation Committee (JCYJ20180504165851864)the support of Research Grants Council Collaborative Research Fund (RGC- CRF) grant C5037-18GSeed Funding for Strategic Interdisciplinary Research Scheme of the University of Hong Kong and Shenzhen Science and Technology Commission Projects (JCYJ20170818141216288)
文摘Perovskite solar cells(PSCs)commonly exhibit significant performance degradation due to ion migration through the top charge transport layer and ultimately metal electrode corrosion.Here,we demonstrate an interfacial management strategy using a boron chloride subphthalocyanine(Cl_(6)SubPc)/fullerene electron-transport layer,which not only passivates the interfacial defects in the perovskite,but also suppresses halide diffusion as evidenced by multiple techniques,including visual element mapping by electron energy loss spectroscopy.As a result,we obtain inverted PSCs with an efficiency of 22.0%(21.3%certified),shelf life of 7000 h,T_(80) of 816 h under damp heat stress(compared to less than 20 h without Cl_(6)SubPc),and initial performance retention of 98%after 2000 h at 80℃in inert environment,90%after 2034 h of illumination and maximum power point tracking in ambient for encapsulated devices and 95%after 1272 h outdoor testing ISOS-O-1.Our strategy and results pave a new way to move PSCs forward to their potential commercialization solidly.
