To extend the absorption capability of TiO_2 into visible light region and inhibit the recombination of photogenerated electrons and holes,we put forward an effective strategy of the coupling of TiO_2 with a suitable ...To extend the absorption capability of TiO_2 into visible light region and inhibit the recombination of photogenerated electrons and holes,we put forward an effective strategy of the coupling of TiO_2 with a suitable semiconductor that possesses a narrow band gap.Meanwhile,Ag_3PO_4-TiO_2 heterostructuralnanotube arrays were prepared by the two-step anodic oxidation to obtain the TiO_2 nanotube arrays and then by a deposition-precipitation method to load Ag_3PO_4.The samples were characterized by field emission scanning electron microscopy（FESEM）,energy dispersive spectrometry（EDS）,X-ray diffraction（XRD）,and UV-vis diffuse reflectance spectroscopy（UV-vis DRS）.The experimentalresults showed that Ag_3PO_4 nanoparticles were uniformly dispersed on the highly ordered TiO_2 nanotube arrays,which increased the visible-light absorption of TiO_2 photocatalyst.The photocurrent density and photocatalytic degradation of methylorange indicated that the performance of Ag_3PO_4-TiO_2 heterostructuralnanotube arrays was better than that of the TiO_2 nanotube arrays,which could be attributed to the effective electron-hole separation and the improved utilization of visible light.展开更多
2,2’,7,7’-tetrakis-(N,N-di-4-methoxyphenylamino)-9,9’-spirobifluorene(spiro-OMeTAD), as the most commonly used hole transport material(HTM), plays a significant role in the normal structured(n-i-p) high-efficiency ...2,2’,7,7’-tetrakis-(N,N-di-4-methoxyphenylamino)-9,9’-spirobifluorene(spiro-OMeTAD), as the most commonly used hole transport material(HTM), plays a significant role in the normal structured(n-i-p) high-efficiency perovskite solar cells(PSCs). In general, it is prepared by a halogen solvent(chlorobenzene, CBZ) and needs an ion dopant(lithium bis(trifluoromethanesulfonyl)imide, Li-TFSI) to improve its conductivity and hole mobility. However, such a halogen solvent is not environmentally friendly and the widely used LiTFSI dopant would affect the stability of PSCs. Herein, we develop a non-halogen solvent-tetrahydrofuran(THF)-prepared spiro-OMeTAD solution with a new p-type dopant,potassium bis(fluorosulfonyl)imide(K-FSI), to apply into PSCs. By this strategy, high-hole-mobility spiro-OMeTAD film is achieved. Meanwhile, the potassium ions introduced by diffusion into perovskite surface passivate the interfacial defects. Therefore, a hysteresis-free champion PSC with an efficiency of 21.02% is obtained, along with significantly improved stability against illumination and ambient conditions. This work provides a new strategy for HTMs toward hysteresis-free high-efficiency and stable PSCs by substituting dopants.展开更多
基金Funded by the Natural Science Foundation of Hubei Province(2012FFB05105)
文摘To extend the absorption capability of TiO_2 into visible light region and inhibit the recombination of photogenerated electrons and holes,we put forward an effective strategy of the coupling of TiO_2 with a suitable semiconductor that possesses a narrow band gap.Meanwhile,Ag_3PO_4-TiO_2 heterostructuralnanotube arrays were prepared by the two-step anodic oxidation to obtain the TiO_2 nanotube arrays and then by a deposition-precipitation method to load Ag_3PO_4.The samples were characterized by field emission scanning electron microscopy（FESEM）,energy dispersive spectrometry（EDS）,X-ray diffraction（XRD）,and UV-vis diffuse reflectance spectroscopy（UV-vis DRS）.The experimentalresults showed that Ag_3PO_4 nanoparticles were uniformly dispersed on the highly ordered TiO_2 nanotube arrays,which increased the visible-light absorption of TiO_2 photocatalyst.The photocurrent density and photocatalytic degradation of methylorange indicated that the performance of Ag_3PO_4-TiO_2 heterostructuralnanotube arrays was better than that of the TiO_2 nanotube arrays,which could be attributed to the effective electron-hole separation and the improved utilization of visible light.
基金financially supported by the National Key Research and Development Plan (2019YFE0107200 and 2017YFE0131900)the National Natural Science Foundation of China (21875178 and 91963209)Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory (XHD2020-001 and XHT2020-005)。
文摘2,2’,7,7’-tetrakis-(N,N-di-4-methoxyphenylamino)-9,9’-spirobifluorene(spiro-OMeTAD), as the most commonly used hole transport material(HTM), plays a significant role in the normal structured(n-i-p) high-efficiency perovskite solar cells(PSCs). In general, it is prepared by a halogen solvent(chlorobenzene, CBZ) and needs an ion dopant(lithium bis(trifluoromethanesulfonyl)imide, Li-TFSI) to improve its conductivity and hole mobility. However, such a halogen solvent is not environmentally friendly and the widely used LiTFSI dopant would affect the stability of PSCs. Herein, we develop a non-halogen solvent-tetrahydrofuran(THF)-prepared spiro-OMeTAD solution with a new p-type dopant,potassium bis(fluorosulfonyl)imide(K-FSI), to apply into PSCs. By this strategy, high-hole-mobility spiro-OMeTAD film is achieved. Meanwhile, the potassium ions introduced by diffusion into perovskite surface passivate the interfacial defects. Therefore, a hysteresis-free champion PSC with an efficiency of 21.02% is obtained, along with significantly improved stability against illumination and ambient conditions. This work provides a new strategy for HTMs toward hysteresis-free high-efficiency and stable PSCs by substituting dopants.
