Graphene is an alternative material for photodetectors owing to its unique properties.These include its uniform absorption of light from ultraviolet to infrared and its ultrahigh mobility for both electrons and holes....Graphene is an alternative material for photodetectors owing to its unique properties.These include its uniform absorption of light from ultraviolet to infrared and its ultrahigh mobility for both electrons and holes.Unfortunately,due to the low absorption of light,the photoresponsivity of graphene-based photodetectors is usually low,only a few milliamps per watt.In this letter,we fabricate a waveguide-integrated graphene photodetector.A photoresponsivity exceeding0.11 A·W (-1) is obtained which enables most optoelectronic applications.The dominating mechanism of photoresponse is investigated and is attributed to the photo-induced bolometric effect.Theoretical calculation shows that the bolometric photoresponsivity is 4.6 A·W (-1).The absorption coefficient of the device is estimated to be 0.27 dB·μm (-1).展开更多
In this article, nano-scale Al/Fe2O3 composites with different morphologies were successfully obtained by a simple electrospinning technique, which is based on a surfactant(polyvinyl pyridine, PVP) in a mixture of N...In this article, nano-scale Al/Fe2O3 composites with different morphologies were successfully obtained by a simple electrospinning technique, which is based on a surfactant(polyvinyl pyridine, PVP) in a mixture of N,N-dimethylformamide(DMF) and 2-propanol. The electrospun Al/Fe2O3 composites exhibited a crystal structure and phase composition by X-ray diffraction analysis. The different morphologies of the Al/Fe2O3 composites were also observed through scanning electron microscopy and transmission electron microscopy. It was found that the rather simple electrospinning method used to prepare the morphology-controlled Al/Fe2O3 composites may have the potential for preparation of propellants, explosives, and pyrotechnics in the future.展开更多
Since silicon is limited by its physical properties,it is challenging and important to find candidate materials for high performance electronic devices.Two-dimensional(2D)semiconductor materials have attracted drama...Since silicon is limited by its physical properties,it is challenging and important to find candidate materials for high performance electronic devices.Two-dimensional(2D)semiconductor materials have attracted dramatically increasing interest due to their unique physical,展开更多
A transparent 3-mercaptopropyl trimethoxysilane(MPTMS)/Ag/MoO3 composite anode is introduced to fabricate green organic light-emitting diodes(OLEDs). Effects of the composite anode on brightness and operating voltage ...A transparent 3-mercaptopropyl trimethoxysilane(MPTMS)/Ag/MoO3 composite anode is introduced to fabricate green organic light-emitting diodes(OLEDs). Effects of the composite anode on brightness and operating voltage of OLEDs are researched. By optimizing the thickness of each layer of the MPTMS/Ag/MoO3 structure, the transmittance of MPTMS/Ag(8 nm)/Mo O3(30 nm) reaches over 75% at about 520 nm. The sheet resistance is 3.78 ?/□, corresponding to this MPTMS/Ag(8 nm)/MoO3(30 nm) structure. For the OLEDs with the optimized anode, the maximum electroluminescence(EL) current efficiency reaches 4.5 cd/A, and the maximum brightness is 37 036 cd/m2. Moreover, the OLEDs with the optimized anode exhibit a very low operating voltage(2.6 V) for obtaining brightness of 100 cd/m2. We consider that the improved device performance is mainly attributed to the enhanced hole injection resulting from the reduced hole injection barrier height. Our results indicate that employing the MPTMS/Ag/MoO3 as a composite anode can be a simple and promising technique in the fabrication of low-operating voltage and high-brightness OLEDs.展开更多
基金Project supported by the National Key Research and Development Program of China(Grant No.2016YFB0402204)the High-Tech Research and Development Program of China(Grant Nos.2013AA031401,2015AA016902,and 2015AA016904)the National Natural Science Foundation of China(Grant Nos.61674136,61176053,61274069,and 61435002)
文摘Graphene is an alternative material for photodetectors owing to its unique properties.These include its uniform absorption of light from ultraviolet to infrared and its ultrahigh mobility for both electrons and holes.Unfortunately,due to the low absorption of light,the photoresponsivity of graphene-based photodetectors is usually low,only a few milliamps per watt.In this letter,we fabricate a waveguide-integrated graphene photodetector.A photoresponsivity exceeding0.11 A·W (-1) is obtained which enables most optoelectronic applications.The dominating mechanism of photoresponse is investigated and is attributed to the photo-induced bolometric effect.Theoretical calculation shows that the bolometric photoresponsivity is 4.6 A·W (-1).The absorption coefficient of the device is estimated to be 0.27 dB·μm (-1).
文摘In this article, nano-scale Al/Fe2O3 composites with different morphologies were successfully obtained by a simple electrospinning technique, which is based on a surfactant(polyvinyl pyridine, PVP) in a mixture of N,N-dimethylformamide(DMF) and 2-propanol. The electrospun Al/Fe2O3 composites exhibited a crystal structure and phase composition by X-ray diffraction analysis. The different morphologies of the Al/Fe2O3 composites were also observed through scanning electron microscopy and transmission electron microscopy. It was found that the rather simple electrospinning method used to prepare the morphology-controlled Al/Fe2O3 composites may have the potential for preparation of propellants, explosives, and pyrotechnics in the future.
基金supported by the National Key Basic Research Program of China(Grant No.2013CB632900)National Natural Science Foundation of China(Grant Nos.61390502&21373068)+1 种基金the Foundation for Innovative Research Groups of the National Natural Science Foundation of China(Grant No.51521003)Self-Planned Task of State Key Laboratory of Robotics and System(HIT)(Grant No.SKLRS201607B)
文摘Since silicon is limited by its physical properties,it is challenging and important to find candidate materials for high performance electronic devices.Two-dimensional(2D)semiconductor materials have attracted dramatically increasing interest due to their unique physical,
基金supported by the National Natural Science Foundation of China(No.21174036)the National High Technology Research and Development Program of China(863 Program)(No.2012AA011901)the National Basic Research Program of China(973 Program)(No.2012CB723406)
文摘A transparent 3-mercaptopropyl trimethoxysilane(MPTMS)/Ag/MoO3 composite anode is introduced to fabricate green organic light-emitting diodes(OLEDs). Effects of the composite anode on brightness and operating voltage of OLEDs are researched. By optimizing the thickness of each layer of the MPTMS/Ag/MoO3 structure, the transmittance of MPTMS/Ag(8 nm)/Mo O3(30 nm) reaches over 75% at about 520 nm. The sheet resistance is 3.78 ?/□, corresponding to this MPTMS/Ag(8 nm)/MoO3(30 nm) structure. For the OLEDs with the optimized anode, the maximum electroluminescence(EL) current efficiency reaches 4.5 cd/A, and the maximum brightness is 37 036 cd/m2. Moreover, the OLEDs with the optimized anode exhibit a very low operating voltage(2.6 V) for obtaining brightness of 100 cd/m2. We consider that the improved device performance is mainly attributed to the enhanced hole injection resulting from the reduced hole injection barrier height. Our results indicate that employing the MPTMS/Ag/MoO3 as a composite anode can be a simple and promising technique in the fabrication of low-operating voltage and high-brightness OLEDs.