It is necessary to evaluate the interactions between the different functional layers in optoelectronic devices to optimize device performance.Recently,the I-rich allinorganic perovskite CsPbI2 Br has attracted tremend...It is necessary to evaluate the interactions between the different functional layers in optoelectronic devices to optimize device performance.Recently,the I-rich allinorganic perovskite CsPbI2 Br has attracted tremendous attention for use in solar cell applications because of its suitable band gap and favorable photo and thermal stabilities.It has been reported that the undesirable phase degradation of the photoactiveαphase CsPbI2 Br to the non-perovskiteδphase could be triggered by high humidity.To obtain stable devices,it is thus important to protect CsPbI2 Br from moisture.In this paper,CuI,a non-hygroscopic p-type hole-transporting material,is found to induce the phase degradation ofα-CsPbI2 Br to theδ-CsPbI2 Br.The rate and extent of phase degradation of CsPbI2 Br are closely associated with the heating temperature and coverage of a Cu I granular capping layer.This discovery is different from the widely reported water-induced phase degradation of CsPbI2 Br.Our work highlights the importance of careful selection of hole-transporting materials during the processing of I-rich all-inorganic CsPbX3(X=Br,I)perovskites to realize high-performance optoelectronic devices.展开更多
Two-dimensional single-crystalline p-n junctions of organic semiconductors(pn-2 DCOSs) show great potential in organic logic circuits due to their single crystal nature and excellent ambipolar charge transport. Howeve...Two-dimensional single-crystalline p-n junctions of organic semiconductors(pn-2 DCOSs) show great potential in organic logic circuits due to their single crystal nature and excellent ambipolar charge transport. However,there are only few reports on pn-2 DCOSs because it is difficult to obtain such highly ordered structure in p-n junction.Herein, a novel and effective solution processing method of secondary transfer technology based on the facile drop casting is used to fabricate devices of pn-2 DCOSs based on C8-BTBT(p-type) and TFT-CN(n-type) successfully. The high-performance ambipolar field transistors based on such ultrathin pn-2 DCOSs with several molecular layers thickness show wellbalanced ambipolar charge transport behaviors with hole mobility as high as 0.43 cm^2 V^-1 s^-1 and electron mobility up to 0.11 cm^2 V^-1 s(^-1), respectively. This work is essential for studying the intrinsic properties of organic p-n junctions and achieving high performance in organic complementary circuits.展开更多
基金supported primarily by the National Key Research and Development Program of China(2018YFA0209303)the National Natural Science Foundation of China(U1663228,51902153,51972165 and 61377051)the Fundamental Research Funds for the Central Universities of China。
文摘It is necessary to evaluate the interactions between the different functional layers in optoelectronic devices to optimize device performance.Recently,the I-rich allinorganic perovskite CsPbI2 Br has attracted tremendous attention for use in solar cell applications because of its suitable band gap and favorable photo and thermal stabilities.It has been reported that the undesirable phase degradation of the photoactiveαphase CsPbI2 Br to the non-perovskiteδphase could be triggered by high humidity.To obtain stable devices,it is thus important to protect CsPbI2 Br from moisture.In this paper,CuI,a non-hygroscopic p-type hole-transporting material,is found to induce the phase degradation ofα-CsPbI2 Br to theδ-CsPbI2 Br.The rate and extent of phase degradation of CsPbI2 Br are closely associated with the heating temperature and coverage of a Cu I granular capping layer.This discovery is different from the widely reported water-induced phase degradation of CsPbI2 Br.Our work highlights the importance of careful selection of hole-transporting materials during the processing of I-rich all-inorganic CsPbX3(X=Br,I)perovskites to realize high-performance optoelectronic devices.
基金financially supported by the Ministry of Science and Technology of China (2016YFB0401100 and 2017YFA0204503)the National Natural Science Foundation of China (51633006, 51725304, 51733004 and 51703159)the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB12030300)
文摘Two-dimensional single-crystalline p-n junctions of organic semiconductors(pn-2 DCOSs) show great potential in organic logic circuits due to their single crystal nature and excellent ambipolar charge transport. However,there are only few reports on pn-2 DCOSs because it is difficult to obtain such highly ordered structure in p-n junction.Herein, a novel and effective solution processing method of secondary transfer technology based on the facile drop casting is used to fabricate devices of pn-2 DCOSs based on C8-BTBT(p-type) and TFT-CN(n-type) successfully. The high-performance ambipolar field transistors based on such ultrathin pn-2 DCOSs with several molecular layers thickness show wellbalanced ambipolar charge transport behaviors with hole mobility as high as 0.43 cm^2 V^-1 s^-1 and electron mobility up to 0.11 cm^2 V^-1 s(^-1), respectively. This work is essential for studying the intrinsic properties of organic p-n junctions and achieving high performance in organic complementary circuits.
