Quantum confinement effect(QCE), an essential physical phenomenon of semiconductors when the size becomes comparable to the exciton Bohr radius, typically results in quite different physical properties of low-dimens...Quantum confinement effect(QCE), an essential physical phenomenon of semiconductors when the size becomes comparable to the exciton Bohr radius, typically results in quite different physical properties of low-dimensional materials from their bulk counterparts and can be exploited to enhance the device performance in various optoelectronic applications. Here, taking Cs Pb Br3 as an example, we reported QCE in all-inorganic halide perovskite in two-dimensional(2D) nanoplates. Blue shifts in optical absorption and photoluminescence spectra were found to be stronger in thinner nanoplates than that in thicker nanoplates, whose thickness lowered below -7 nm. The exciton binding energy results showed similar trend as that obtained for the optical absorption and photoluminescence. Meanwile, the function of integrated intensity and full width at half maximum and temperature also showed similar results, further supporting our conclusions. The results displayed the QCE in all-inorganic halide perovskite nanoplates and helped to design the all-inorganic halide perovskites with desired optical properties.展开更多
In this paper,the pentacene-based organic field-effect transistors(OFETs)with poly(methyl methacrylate)(PMMA)as gate dielectrics were fabricated,and the effects of gate dielectric thickness and semiconductor thickness...In this paper,the pentacene-based organic field-effect transistors(OFETs)with poly(methyl methacrylate)(PMMA)as gate dielectrics were fabricated,and the effects of gate dielectric thickness and semiconductor thickness on the device performance were investigated.The optimal PMMA thickness is in the range of 350–400 nm to sustain a considerable current density and stable performance.The device performance depends on the thicknesses of the active layer non-monotonically,which can be explained by the morphology of the pentacene film and the position of the conducting channel in the active layer.The device with a pentacene thickness of 50 nm shows the best performance,which has a maximum hole mobility of 1.12 cm2/V·s.In addition,the introduction of a thin layer of tris-(8-hydroxyquinolinato)aluminum(Alq3)to the OFETs as a light-emitting material greatly decreases the device performance.展开更多
基金supported by the National Basic Research Program of China (2014CB931702)the National Key Research and Development Program of China (2016YFB0401701)+5 种基金the National Natural Science Foundation of China (NSFC 51572128 and 21403109)NSFC-RGC (5151101197)the Natural Science Foundation of Jiangsu Province (BK20160827)China Postdoctoral Science Foundation (2016M590455)the Fundamental Research Funds for the Central Universities (30915012205 and 30916015106)the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)
文摘Quantum confinement effect(QCE), an essential physical phenomenon of semiconductors when the size becomes comparable to the exciton Bohr radius, typically results in quite different physical properties of low-dimensional materials from their bulk counterparts and can be exploited to enhance the device performance in various optoelectronic applications. Here, taking Cs Pb Br3 as an example, we reported QCE in all-inorganic halide perovskite in two-dimensional(2D) nanoplates. Blue shifts in optical absorption and photoluminescence spectra were found to be stronger in thinner nanoplates than that in thicker nanoplates, whose thickness lowered below -7 nm. The exciton binding energy results showed similar trend as that obtained for the optical absorption and photoluminescence. Meanwile, the function of integrated intensity and full width at half maximum and temperature also showed similar results, further supporting our conclusions. The results displayed the QCE in all-inorganic halide perovskite nanoplates and helped to design the all-inorganic halide perovskites with desired optical properties.
基金supported by the National Natural Science Foundation of China(Grant Nos.61177017,61275175,61036007,61377028,and 61077022)National Science Foundation for Distinguished Young Scholars of China(Grant No.61125505)the"111" Project of China(Grant No.B08002)
文摘In this paper,the pentacene-based organic field-effect transistors(OFETs)with poly(methyl methacrylate)(PMMA)as gate dielectrics were fabricated,and the effects of gate dielectric thickness and semiconductor thickness on the device performance were investigated.The optimal PMMA thickness is in the range of 350–400 nm to sustain a considerable current density and stable performance.The device performance depends on the thicknesses of the active layer non-monotonically,which can be explained by the morphology of the pentacene film and the position of the conducting channel in the active layer.The device with a pentacene thickness of 50 nm shows the best performance,which has a maximum hole mobility of 1.12 cm2/V·s.In addition,the introduction of a thin layer of tris-(8-hydroxyquinolinato)aluminum(Alq3)to the OFETs as a light-emitting material greatly decreases the device performance.