Te-doped GaSb single crystals are studied by measuring Hall effect, infrared （IR） transmission and photoluminescence （PL） spectra. It is found that the n-type GaSb with IR transmittance can be obtained as high as ...Te-doped GaSb single crystals are studied by measuring Hall effect, infrared （IR） transmission and photoluminescence （PL） spectra. It is found that the n-type GaSb with IR transmittance can be obtained as high as 60% by the critical control of the Te-doping concentration and electrical compensation. The concentration of the native acceptor-associated defects is apparently low in the Te-doped GaSb compared with those in undoped and heavily Te-doped GaSb. The mechanism for the high IR transmittance is analyzed by considering the defect-involved optical absorption process.展开更多
In this work the influence of aqueous sulfur passivation on the surface of n-type (100) GaSb single crystals has been studied through low-temperature photoluminescence (PL) characterization. The samples were passivate...In this work the influence of aqueous sulfur passivation on the surface of n-type (100) GaSb single crystals has been studied through low-temperature photoluminescence (PL) characterization. The samples were passivated at different times using aqueous solutions of sodium sulfide. PL spectroscopy was used to determinate the optimum time of sulfur passivation, through the measurement of the PL intensity for the different passivation times. For the samples measured, the PL spectra show the presence of two emission bands, whose intensity and energy position change for the different passivation times of the GaSb samples. According to the PL results, a passivation surface treatment of 6 min shows the highest PL intensity spectrum.展开更多
Due to its ability to convert body heat into electricity,organic thermoelectric material is considered a promising and smart maintenance-free power source to charge wearable electronics.However,developing flexible n-t...Due to its ability to convert body heat into electricity,organic thermoelectric material is considered a promising and smart maintenance-free power source to charge wearable electronics.However,developing flexible n-type organic thermoelectric materials and wearable p/n junction thermoelectric devices remains challenging.In this work,two insulated polyamides(PA6 and PA66)that have been widely used as fiber materials are employed as novel dopants for converting p-type single-walled carbon nanotubes(SWCNTs)to n-type thermoelectric materials.Because of the electron transferability of the amide group,polyamide-doped SWCNTs exhibit excellent thermopower values as large as-56.0μV K^(-1) for PA66,and-54.5μV K^(-1) for PA6.Thermoelectric devices with five p/n junctions connected in series are fabricated.The testing device produces a thermoelectric voltage of 43.1 mV and generates 1.85μW thermoelectric power under temperature gradients of approximately 80 K.Furthermore,they display charming capability for temperature recognition and monitoring human activities as sensors.These promising results suggest that the flexible polyamide-doped SWCNT composites herein have high application potential as wearable thermoelectric electronics.展开更多
Regioselevtive functionalization of perylene diimides(PDIs)at bay area often requires multistep synthesis and strenuous recrystallization.Direct bromination of perylene diimides only afford the 1,6 and 1,7-regioisomer...Regioselevtive functionalization of perylene diimides(PDIs)at bay area often requires multistep synthesis and strenuous recrystallization.Direct bromination of perylene diimides only afford the 1,6 and 1,7-regioisomers.More importantly,the 1,6-dibromo regioisomers could only be separated by preparative HPLC.Herein,we report a promising strategy for constructing Janus backbone of BN-doped perylene diimide derivatives.This Janus-type configuration results in the unique regioselective functionalization of BN-JPDIs,which yields exclusively the 1,6-regioisomers.Further investigation shows that the Janus-type configuration leads to a net dipole moment of 1.94 D and intramolecular charge transfer,which causes substantial changes on the optoelectronic properties.Moreover,the single crystal organic field-effect transistors based on BN-JPDIs exhibit electron mobilities up to 0.57 cm^(2)V^(-1)s^(-1),showcasing their potential as versatile building block towards high-performance n-type organic semiconductors.展开更多
In this paper,a planar junction mid-wavelength infrared(MWIR)photodetector based on an InAs/GaSb type-Ⅱsuper-lattices(T2SLs)is reported.The Intrinsic-πMN superlattices was grown by the molecular beam epitaxy(MBE),fo...In this paper,a planar junction mid-wavelength infrared(MWIR)photodetector based on an InAs/GaSb type-Ⅱsuper-lattices(T2SLs)is reported.The Intrinsic-πMN superlattices was grown by the molecular beam epitaxy(MBE),followed with a ZnS layer grown by the chemical vapor deposition(CVD).The p-type contact layer was constructed by thermal diffusion in the undoped superlattices.The Zinc atom was successfully realised into the superlattice and a PπMN T2SL structure was con-structed.Furthermore,the effects of different diffusion temperatures on the dark current performance of the devices were researched.The 50%cut-off wavelength of the photodetector is 5.26μm at 77 K with 0 V bias.The minimum dark current density is 8.67×10^(−5) A/cm^(2) and the maximum quantum efficiency of 42.5%,and the maximum detectivity reaches 3.90×10^(10) cm·Hz^(1/2)/W at 77 K.The 640×512 focal plane arrays(FPA)based on the planner junction were fabricated afterwards.The FPA achieves a noise equivalent temperature difference(NETD)of 539 mK.展开更多
With high surface-to-volume ratio,the abundant surface states and high carrier concentration are challenging the nearinfrared photodetection behaviors of narrow band gap semiconductors nanowires.In this study,the narr...With high surface-to-volume ratio,the abundant surface states and high carrier concentration are challenging the nearinfrared photodetection behaviors of narrow band gap semiconductors nanowires.In this study,the narrow band gap semiconductor of Bi_(2)O_(2)Se nanosheets(NSs)is adopted to construct mixed-dimensional heterojunctions with GaSb nanowires(NWs)for demonstrating the impressive self-powered NIR photodetection.Benefiting from the built-in electric field of~140 meV,the as-constructed NW/NS mixeddimensional heterojunction self-powered photodetector shows the low dark current of 0.07 pA,high I_(light)/I_(dark)ratio of 82 and fast response times of<2/2 ms at room temperature.The self-powered photodetector performance can be further enhanced by fabricating the NW array/NS mixed-dimensional heterojunction by using a contact printing technique.The excellent photodetection performance promises the asconstructed NW/NS mixed-dimensional heterojunction self-powered photodetector in imaging and photocommunication.展开更多
本文报道了1280×1024元InAs/GaSb II类超晶格中/中波双色红外焦平面阵列探测器的研究结果。探测器采用PN-NP叠层双色外延结构,信号提取采用叠层双色结构和顺序读出方式。运用分子束外延技术在GaSb衬底上生长超晶格材料,双波段红外...本文报道了1280×1024元InAs/GaSb II类超晶格中/中波双色红外焦平面阵列探测器的研究结果。探测器采用PN-NP叠层双色外延结构,信号提取采用叠层双色结构和顺序读出方式。运用分子束外延技术在GaSb衬底上生长超晶格材料,双波段红外吸收区的超晶格周期结构分别为中波1:6 ML InAs/7 ML GaSb和中波2:9 ML InAs/7 ML GaSb。焦平面阵列像元中心距为12μm。在80 K时测试,器件双波段的工作谱段为中波1:3~4μm,中波2:3.8~5.2μm。中波1器件平均峰值探测率达到6.32×10^(11) cm·Hz^(1/2)W^(-1),中波2器件平均峰值探测率达到2.84×10^(11) cm·Hz^(1/2)W^(-1)。红外焦平面偏压调节成像测试得到清晰的双波段成像。本文是国内首次报道1280×1024规模InAs/GaSb II类超晶格中/中波双色红外焦平面探测器。展开更多
The thermoelectric power factor is as crucial as their overall thermoelectric performance.GaSb-based compounds are deemed to achieve high power factor owing to their intrinsically high mobility compared to classical t...The thermoelectric power factor is as crucial as their overall thermoelectric performance.GaSb-based compounds are deemed to achieve high power factor owing to their intrinsically high mobility compared to classical thermoelectric materials.However,the carrier concentration of pristine GaSb is considerably lower than the optimum value,which hinders its ability to attain high electrical performance.In this paper,we present the investigations on the thermoelectric performance of p-type GaSb_(1-x)Ge_(x)samples.The experimental results reveal that Ge doping can effectively tune the carrier concentration.展开更多
Doped two-dimensional(2D)materials hold significant promise for advancing many technologies,such as microelectronics,optoelectronics,and energy storage.Herein,n-type 2D oxidized Si nanosheets,namely n-type siloxene(n-...Doped two-dimensional(2D)materials hold significant promise for advancing many technologies,such as microelectronics,optoelectronics,and energy storage.Herein,n-type 2D oxidized Si nanosheets,namely n-type siloxene(n-SX),are employed as Li-ion battery anodes.Via thermal evaporation of sodium hypophosphite at 275℃,P atoms are effectively incorporated into siloxene(SX)without compromising its 2D layered morphology and unique Kautsky-type crystal structure.Further,selective nucleophilic substitution occurs,with only Si atoms being replaced by P atoms in the O_(3)≡Si-H tetrahedra.The resulting n-SX possesses two delocalized electrons arising from the presence of two electron donor types:(i)P atoms residing in Si sites and(ii)H vacancies.The doping concentrations are varied by controlling the amount of precursors or their mean free paths.Even at 2000 mA g^(-1),the n-SX electrode with the optimized doping concentration(6.7×10^(19) atoms cm^(-3))delivers a capacity of 594 mAh g^(-1) with a 73%capacity retention after 500 cycles.These improvements originate from the enhanced kinetics of charge transport processes,including electronic conduction,charge transfer,and solid-state diffusion.The approach proposed herein offers an unprecedented route for engineering SX anodes to boost Li-ion storage.展开更多
The development of n-type semiconductor is still far behind that of p-type semiconductor on account of the challenges in enhancing carrier mobility and environmental stability.Herein,by blending with the polymers,n-ty...The development of n-type semiconductor is still far behind that of p-type semiconductor on account of the challenges in enhancing carrier mobility and environmental stability.Herein,by blending with the polymers,n-type ultrathin crystalline thin film was successfully prepared by the method of meniscus-guided coating.Remarkably,the n-type crystalline films exhibit ultrathin thickness as low as 5 nm and excellent mobility of 1.58 cm^(2) V^(-1) s^(-1),which is outstanding in currently reported organic n-type transistors.Moreover,the PS layer provides a high-quality interface with ultralow defect which has strong resistance to external interference with excellent long-term stability,paving the way for the application of n-type transistors in logic circuits.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.61474104 and 61504131)
文摘Te-doped GaSb single crystals are studied by measuring Hall effect, infrared （IR） transmission and photoluminescence （PL） spectra. It is found that the n-type GaSb with IR transmittance can be obtained as high as 60% by the critical control of the Te-doping concentration and electrical compensation. The concentration of the native acceptor-associated defects is apparently low in the Te-doped GaSb compared with those in undoped and heavily Te-doped GaSb. The mechanism for the high IR transmittance is analyzed by considering the defect-involved optical absorption process.
基金partially supported by the ICyTDF and CONACYT,México
文摘In this work the influence of aqueous sulfur passivation on the surface of n-type (100) GaSb single crystals has been studied through low-temperature photoluminescence (PL) characterization. The samples were passivated at different times using aqueous solutions of sodium sulfide. PL spectroscopy was used to determinate the optimum time of sulfur passivation, through the measurement of the PL intensity for the different passivation times. For the samples measured, the PL spectra show the presence of two emission bands, whose intensity and energy position change for the different passivation times of the GaSb samples. According to the PL results, a passivation surface treatment of 6 min shows the highest PL intensity spectrum.
基金supported by the National Natural Science Foundation of China(Project no.51973120)the Natural Science Foun-dation of Guangdong Province(No.2019A1515010613)+1 种基金the Shenzhen Science and Technology Research Grant(Nos.JCYJ20170818093417096 and JCYJ20180305125649693)the Shenzhen Science and Technology Program(No.20220809111527001).
文摘Due to its ability to convert body heat into electricity,organic thermoelectric material is considered a promising and smart maintenance-free power source to charge wearable electronics.However,developing flexible n-type organic thermoelectric materials and wearable p/n junction thermoelectric devices remains challenging.In this work,two insulated polyamides(PA6 and PA66)that have been widely used as fiber materials are employed as novel dopants for converting p-type single-walled carbon nanotubes(SWCNTs)to n-type thermoelectric materials.Because of the electron transferability of the amide group,polyamide-doped SWCNTs exhibit excellent thermopower values as large as-56.0μV K^(-1) for PA66,and-54.5μV K^(-1) for PA6.Thermoelectric devices with five p/n junctions connected in series are fabricated.The testing device produces a thermoelectric voltage of 43.1 mV and generates 1.85μW thermoelectric power under temperature gradients of approximately 80 K.Furthermore,they display charming capability for temperature recognition and monitoring human activities as sensors.These promising results suggest that the flexible polyamide-doped SWCNT composites herein have high application potential as wearable thermoelectric electronics.
基金support from the National Natural Science Foundation of China(Nos.22071007,22020102001,22335002)the National Key R&D Program of China(No.2022YFB3602802)+3 种基金Beijing Natural Science Foundation(No.Z220025)the National Facility for Protein Science in Shanghai,Shanghai Advanced Research Institute,CAS,for providing technical support in X-ray diffraction data collectionthe High-Performance Computing Platform of Peking University for supporting the computational workthe support of BMS Junior Fellow program。
文摘Regioselevtive functionalization of perylene diimides(PDIs)at bay area often requires multistep synthesis and strenuous recrystallization.Direct bromination of perylene diimides only afford the 1,6 and 1,7-regioisomers.More importantly,the 1,6-dibromo regioisomers could only be separated by preparative HPLC.Herein,we report a promising strategy for constructing Janus backbone of BN-doped perylene diimide derivatives.This Janus-type configuration results in the unique regioselective functionalization of BN-JPDIs,which yields exclusively the 1,6-regioisomers.Further investigation shows that the Janus-type configuration leads to a net dipole moment of 1.94 D and intramolecular charge transfer,which causes substantial changes on the optoelectronic properties.Moreover,the single crystal organic field-effect transistors based on BN-JPDIs exhibit electron mobilities up to 0.57 cm^(2)V^(-1)s^(-1),showcasing their potential as versatile building block towards high-performance n-type organic semiconductors.
基金supported by the National Key Technologies R&D Program of China(Grant Nos.2024YFA1208904,2019YFA0705203)Major Program of the National Natural Science Foundation of China(Grant Nos.62004189,61274013)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB0460000)the Research Foundation for Advanced Talents of the Chinese Academy of Sciences(Grant No.E27RBB03).
文摘In this paper,a planar junction mid-wavelength infrared(MWIR)photodetector based on an InAs/GaSb type-Ⅱsuper-lattices(T2SLs)is reported.The Intrinsic-πMN superlattices was grown by the molecular beam epitaxy(MBE),followed with a ZnS layer grown by the chemical vapor deposition(CVD).The p-type contact layer was constructed by thermal diffusion in the undoped superlattices.The Zinc atom was successfully realised into the superlattice and a PπMN T2SL structure was con-structed.Furthermore,the effects of different diffusion temperatures on the dark current performance of the devices were researched.The 50%cut-off wavelength of the photodetector is 5.26μm at 77 K with 0 V bias.The minimum dark current density is 8.67×10^(−5) A/cm^(2) and the maximum quantum efficiency of 42.5%,and the maximum detectivity reaches 3.90×10^(10) cm·Hz^(1/2)/W at 77 K.The 640×512 focal plane arrays(FPA)based on the planner junction were fabricated afterwards.The FPA achieves a noise equivalent temperature difference(NETD)of 539 mK.
基金the Natural Science Foundation of Shandong Province(Nos.ZR2022JQ05 and ZR2024MF010).
文摘With high surface-to-volume ratio,the abundant surface states and high carrier concentration are challenging the nearinfrared photodetection behaviors of narrow band gap semiconductors nanowires.In this study,the narrow band gap semiconductor of Bi_(2)O_(2)Se nanosheets(NSs)is adopted to construct mixed-dimensional heterojunctions with GaSb nanowires(NWs)for demonstrating the impressive self-powered NIR photodetection.Benefiting from the built-in electric field of~140 meV,the as-constructed NW/NS mixeddimensional heterojunction self-powered photodetector shows the low dark current of 0.07 pA,high I_(light)/I_(dark)ratio of 82 and fast response times of<2/2 ms at room temperature.The self-powered photodetector performance can be further enhanced by fabricating the NW array/NS mixed-dimensional heterojunction by using a contact printing technique.The excellent photodetection performance promises the asconstructed NW/NS mixed-dimensional heterojunction self-powered photodetector in imaging and photocommunication.
文摘本文报道了1280×1024元InAs/GaSb II类超晶格中/中波双色红外焦平面阵列探测器的研究结果。探测器采用PN-NP叠层双色外延结构,信号提取采用叠层双色结构和顺序读出方式。运用分子束外延技术在GaSb衬底上生长超晶格材料,双波段红外吸收区的超晶格周期结构分别为中波1:6 ML InAs/7 ML GaSb和中波2:9 ML InAs/7 ML GaSb。焦平面阵列像元中心距为12μm。在80 K时测试,器件双波段的工作谱段为中波1:3~4μm,中波2:3.8~5.2μm。中波1器件平均峰值探测率达到6.32×10^(11) cm·Hz^(1/2)W^(-1),中波2器件平均峰值探测率达到2.84×10^(11) cm·Hz^(1/2)W^(-1)。红外焦平面偏压调节成像测试得到清晰的双波段成像。本文是国内首次报道1280×1024规模InAs/GaSb II类超晶格中/中波双色红外焦平面探测器。
基金financially supported by the National Natural Science Foundation of China(Nos.12004060 and 12204080)the Natural Science Foundation of Chongqing(No.CSTB2022NSCQ-MSX0382)the Scientific and Technological Research Program of Chongqing Municipal Education Commission(Nos.KJQN202000635 and KJQN 202200623)。
文摘The thermoelectric power factor is as crucial as their overall thermoelectric performance.GaSb-based compounds are deemed to achieve high power factor owing to their intrinsically high mobility compared to classical thermoelectric materials.However,the carrier concentration of pristine GaSb is considerably lower than the optimum value,which hinders its ability to attain high electrical performance.In this paper,we present the investigations on the thermoelectric performance of p-type GaSb_(1-x)Ge_(x)samples.The experimental results reveal that Ge doping can effectively tune the carrier concentration.
基金supported by the Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(2020R1A6A1A03045059)+1 种基金by Ministry of Science and ICT(2022R1A2C3003319)by the Institutional Program(2E33221)of the Korea Institute of Science and Technology(KIST).
文摘Doped two-dimensional(2D)materials hold significant promise for advancing many technologies,such as microelectronics,optoelectronics,and energy storage.Herein,n-type 2D oxidized Si nanosheets,namely n-type siloxene(n-SX),are employed as Li-ion battery anodes.Via thermal evaporation of sodium hypophosphite at 275℃,P atoms are effectively incorporated into siloxene(SX)without compromising its 2D layered morphology and unique Kautsky-type crystal structure.Further,selective nucleophilic substitution occurs,with only Si atoms being replaced by P atoms in the O_(3)≡Si-H tetrahedra.The resulting n-SX possesses two delocalized electrons arising from the presence of two electron donor types:(i)P atoms residing in Si sites and(ii)H vacancies.The doping concentrations are varied by controlling the amount of precursors or their mean free paths.Even at 2000 mA g^(-1),the n-SX electrode with the optimized doping concentration(6.7×10^(19) atoms cm^(-3))delivers a capacity of 594 mAh g^(-1) with a 73%capacity retention after 500 cycles.These improvements originate from the enhanced kinetics of charge transport processes,including electronic conduction,charge transfer,and solid-state diffusion.The approach proposed herein offers an unprecedented route for engineering SX anodes to boost Li-ion storage.
基金the financial support of the National Key Research and Development Program(No.2022YFF1202700)National Natural Science Foundation of China(No.52121002)the Haihe Laboratory of Sustainable Chemical Transformations.
文摘The development of n-type semiconductor is still far behind that of p-type semiconductor on account of the challenges in enhancing carrier mobility and environmental stability.Herein,by blending with the polymers,n-type ultrathin crystalline thin film was successfully prepared by the method of meniscus-guided coating.Remarkably,the n-type crystalline films exhibit ultrathin thickness as low as 5 nm and excellent mobility of 1.58 cm^(2) V^(-1) s^(-1),which is outstanding in currently reported organic n-type transistors.Moreover,the PS layer provides a high-quality interface with ultralow defect which has strong resistance to external interference with excellent long-term stability,paving the way for the application of n-type transistors in logic circuits.
