The Fluorescence excitation spectrum, emission spectrum and infrared up conversion luminescence excitation spectrum are measured. The results of spectrum measurement show that the electron trapping materials CaS: Eu, ...The Fluorescence excitation spectrum, emission spectrum and infrared up conversion luminescence excitation spectrum are measured. The results of spectrum measurement show that the electron trapping materials CaS: Eu, Sm are of visible light excitation. The mechanism of visible light excitation is analyzed.展开更多
Trivalent rare-earth ions （La3＋,Pr3＋,Nd3＋,Sm3＋,Gd3＋,Tb3＋,Dy3＋,Ho3＋,Er3＋,Tm3＋,and Yb3＋） were investigated as the codoped auxiliary sensitizer for the electron trapping materials SrS：Eu2＋ in order to enha...Trivalent rare-earth ions （La3＋,Pr3＋,Nd3＋,Sm3＋,Gd3＋,Tb3＋,Dy3＋,Ho3＋,Er3＋,Tm3＋,and Yb3＋） were investigated as the codoped auxiliary sensitizer for the electron trapping materials SrS：Eu2＋ in order to enhance the fluorescence properties.It was found that Sm3＋ and Tb3＋ had the best photoluminescence stimulated luminescence （PSL） effect among the selected trivalent rare-earth ions.All the SrS：Eu2＋ samples doped by different trivalent rare-earth ions could be stimulated by 980 nm laser after being exposed to the conventional sunlight,and they emitted PSL with the peak located at 615 nm.The result also indicated that some co-doped rare earth ions could increase fluorescence intensities of the traditional electron trapping materials SrS：Eu2＋.展开更多
To enhance device performance and reduce fabrication cost,a series of electron transporting material(ETM)-free perovskite solar cells(PSCs)is developed by TCAD Atlas.The accuracy of the physical mode of PSCs is verifi...To enhance device performance and reduce fabrication cost,a series of electron transporting material(ETM)-free perovskite solar cells(PSCs)is developed by TCAD Atlas.The accuracy of the physical mode of PSCs is verified,due to the simulations of PEDOT:PSS-CH_(3)NH_(3)PbI_(3)-PCBM and CuSCN-CH_(3)NH_(3)PbI_(3)-PCBM p-i-n PSCs showing a good agreement with experimental results.Different hole transporting materials(HTMs)are selected and directly combined with n-CH_(3)NH_(3)PbI_(3),and the CuSCN-CH_(3)NH_(3)PbI_(3) is the best in these ETM-free PSCs.To further study the CuSCN-CH_(3)NH_(3)PbI_(3) PSC,the influences of back electrode material,gradient band gap,thickness,doping concentration,and bulk defect density on the performance are investigated.Energy band and distribution of electric field are utilized to optimize the design.As a result,the efficiency of CuSCN-CH_(3)NH_(3)PbI_(3) PSC is achieved to be 26.64%.This study provides the guideline for designing and improving the performances of ETM-free PSCs.展开更多
Hundreds of C60 derivatives stand out as electrontransporting materials(ETMs), for example, in perovskite solar cells(PSCs), due to their properties on electron extraction or defect passivation. However, it still lack...Hundreds of C60 derivatives stand out as electrontransporting materials(ETMs), for example, in perovskite solar cells(PSCs), due to their properties on electron extraction or defect passivation. However, it still lacks of guidelines to update C60-based ETMs with excellent photoelectric properties. In this work, crystallographic data of eight C60-based ETMs, including pristine C60 and the well-known PCBM as well as six newly synthesized fullerenes, are analyzed to establish the connections between derivatized structures and photoelectric properties for the typical carbon cluster of C60. In terms of packing centroid-centroid distance between neighboring carbon cages, the crystallographic data are useful for probing photoelectric properties, such as electrochemical properties, electron mobility and photovoltaic performances, and therefore facilitate to design novel C60-based ETMs for PSCs with high performances.展开更多
文摘The Fluorescence excitation spectrum, emission spectrum and infrared up conversion luminescence excitation spectrum are measured. The results of spectrum measurement show that the electron trapping materials CaS: Eu, Sm are of visible light excitation. The mechanism of visible light excitation is analyzed.
基金Project supported by the National Natural Science Foundations of China (20876002, 20976002)the Beijing Natural Science Foundation (2091002)Funding Project for Academic Human Resources Development in Institutions of Higher Learning under the Jurisdiction of Beijing Municipality
文摘Trivalent rare-earth ions （La3＋,Pr3＋,Nd3＋,Sm3＋,Gd3＋,Tb3＋,Dy3＋,Ho3＋,Er3＋,Tm3＋,and Yb3＋） were investigated as the codoped auxiliary sensitizer for the electron trapping materials SrS：Eu2＋ in order to enhance the fluorescence properties.It was found that Sm3＋ and Tb3＋ had the best photoluminescence stimulated luminescence （PSL） effect among the selected trivalent rare-earth ions.All the SrS：Eu2＋ samples doped by different trivalent rare-earth ions could be stimulated by 980 nm laser after being exposed to the conventional sunlight,and they emitted PSL with the peak located at 615 nm.The result also indicated that some co-doped rare earth ions could increase fluorescence intensities of the traditional electron trapping materials SrS：Eu2＋.
基金the Fundamental Research Funds for the Central Universities of China(Grant No.JD2020JGPY0010)the China Post-Doctoral Science Foundation(Grant No.2020M671834).
文摘To enhance device performance and reduce fabrication cost,a series of electron transporting material(ETM)-free perovskite solar cells(PSCs)is developed by TCAD Atlas.The accuracy of the physical mode of PSCs is verified,due to the simulations of PEDOT:PSS-CH_(3)NH_(3)PbI_(3)-PCBM and CuSCN-CH_(3)NH_(3)PbI_(3)-PCBM p-i-n PSCs showing a good agreement with experimental results.Different hole transporting materials(HTMs)are selected and directly combined with n-CH_(3)NH_(3)PbI_(3),and the CuSCN-CH_(3)NH_(3)PbI_(3) is the best in these ETM-free PSCs.To further study the CuSCN-CH_(3)NH_(3)PbI_(3) PSC,the influences of back electrode material,gradient band gap,thickness,doping concentration,and bulk defect density on the performance are investigated.Energy band and distribution of electric field are utilized to optimize the design.As a result,the efficiency of CuSCN-CH_(3)NH_(3)PbI_(3) PSC is achieved to be 26.64%.This study provides the guideline for designing and improving the performances of ETM-free PSCs.
基金This work was supported by the National Nature Science Foundation of China (Nos.92061122,92061204,21721001)the China Postdoctoral Science Foundation(No.2020M680197)the Natural Science Foundation of Guangxi Province of China(No.2020GXNSFBA159037).
文摘Hundreds of C60 derivatives stand out as electrontransporting materials(ETMs), for example, in perovskite solar cells(PSCs), due to their properties on electron extraction or defect passivation. However, it still lacks of guidelines to update C60-based ETMs with excellent photoelectric properties. In this work, crystallographic data of eight C60-based ETMs, including pristine C60 and the well-known PCBM as well as six newly synthesized fullerenes, are analyzed to establish the connections between derivatized structures and photoelectric properties for the typical carbon cluster of C60. In terms of packing centroid-centroid distance between neighboring carbon cages, the crystallographic data are useful for probing photoelectric properties, such as electrochemical properties, electron mobility and photovoltaic performances, and therefore facilitate to design novel C60-based ETMs for PSCs with high performances.
