Two-dimensional(2D)materials are intensively attractive for fabricating high sensitive photodetectors in terms of atomically thin flexible and ultrafast charge transport feature.Due to their atomically thin body,desig...Two-dimensional(2D)materials are intensively attractive for fabricating high sensitive photodetectors in terms of atomically thin flexible and ultrafast charge transport feature.Due to their atomically thin body,designing high performance detector requires new physical mechanisms and device structures.In this review,we classify design strategies and device structures into four categories depending on their physical mechanisms(photovoltaic effect,photoconductive effect,photothermoelectric effect or photobolometric effect,and surface plasma-wave-assisted effect),and summarize the device performances.Finally,future prospects and development direction for 2D material photodetectors are described.Those design strategies descriptions about photoelectronic detector provide a reference for high responsivity and fast response speed photodetector at broadband sensing in the future.展开更多
Si-based multilayer structures are widely used in current microelectronics. During their preparation, some inhomogeneous residual stress is induced, resulting in competition between interface mismatching and surface e...Si-based multilayer structures are widely used in current microelectronics. During their preparation, some inhomogeneous residual stress is induced, resulting in competition between interface mismatching and surface energy and even leading to structure failure. This work presents a methodological study on the measurement of residual stress in a multi-layer semiconductor heterostructure. Scanning electron microscopy（SEM）, micro-Raman spectroscopy（MRS）, and transmission electron microscopy（TEM） were applied to measure the geometric parameters of the multilayer structure. The relationship between the Raman spectrum and the stress/strain on the [100] and [110] crystal orientations was determined to enable surface and crosssection residual stress analyses, respectively. Based on the Raman mapping results, the distribution of residual stress along the depth of the multi-layer heterostructure was successfully obtained.展开更多
A high-performance and broadband heterojunction photodetector has been successfully fabricated.The heterostructure device is based on a uniform and pinhole-free perovskite film constructed on top of a single-crystal g...A high-performance and broadband heterojunction photodetector has been successfully fabricated.The heterostructure device is based on a uniform and pinhole-free perovskite film constructed on top of a single-crystal germanium layer.The perovskite/germanium photodetector shows enhanced performance and a broad spectrum compared with the single-material-based device.The photon response properties are characterized in detail from the visible to near-infrared spectrum.At an optical fibre communication wavelength of 1550 nm,the heterojunction device exhibits the highest responsivity of 1.4 A/W.The performance is promoted because of an antireflection perovskite coating,the thickness of which is optimized to 150 nm at the telecommunication band.At a visible light wavelength of 680 nm,the device shows outstanding responsivity and detectivity of 228 A/W and 1.6×10^(10) Jones,respectively.These excellent properties arise from the photoconductive gain boost in the heterostructure device.The presented heterojunction photodetector provides a competitive approach for wide-spectrum photodetection from visible to optical communication areas.Based on the distinguished capacity of light detection and harvesting from the visible to near-infrared spectrum,the designed germanium/perovskite heterostructure configuration is believed to provide new building blocks for novel optoelectronic devices.展开更多
以硝酸铜为前驱体,不采用任何模板,通过逐步水热法合成了花状Cu2O/Cu复合纳米材料.用扫描电镜(SEM)、X射线衍射(XRD)和紫外-可见漫反射光谱(DRS)对样品进行表征.结果表明,花状纳米Cu2O/Cu材料是由长为300-500nm,宽为30-70nm的带状花瓣构...以硝酸铜为前驱体,不采用任何模板,通过逐步水热法合成了花状Cu2O/Cu复合纳米材料.用扫描电镜(SEM)、X射线衍射(XRD)和紫外-可见漫反射光谱(DRS)对样品进行表征.结果表明,花状纳米Cu2O/Cu材料是由长为300-500nm,宽为30-70nm的带状花瓣构成,在可见光区域有很强的吸收.复合材料中Cu的含量可以通过反应时间进行调控.对染料Procion Red MX-5B(PR)的可见光催化降解,Cu能明显提高Cu2O的光催化性能.当Cu质量分数为27%-71%时,复合材料Cu2O/Cu的催化活性明显高于单相Cu2O.与立方体形貌的Cu2O/Cu复合材料相比,花状纳米Cu2O/Cu复合材料对染料PR有更高的催化降解性能.且该复合材料有较高的循环回收利用率.展开更多
Two-dimensional(2D) materials have attracted extensive interest due to their excellent electrical, thermal,mechanical, and optical properties. Graphene has been one of the most explored 2D materials. However, its zero...Two-dimensional(2D) materials have attracted extensive interest due to their excellent electrical, thermal,mechanical, and optical properties. Graphene has been one of the most explored 2D materials. However, its zero band gap has limited its applications in electronic devices. Transition metal dichalcogenide(TMDC), another kind of 2D material,has a nonzero direct band gap(same charge carrier momentum in valence and conduction band) at monolayer state,promising for the efficient switching devices(e.g., field-effect transistors). This review mainly focuses on the recent advances in charge carrier mobility and the challenges to achieve high mobility in the electronic devices based on 2DTMDC materials and also includes an introduction of 2D materials along with the synthesis techniques. Finally, this review describes the possible methodology and future prospective to enhance the charge carrier mobility for electronic devices.展开更多
It is a rapidly developed subject in expanding the fundamental properties and application of two-dimensional(2D)materials.The weak van der Waals interaction in 2D materials inspired researchers to explore 2D heterostr...It is a rapidly developed subject in expanding the fundamental properties and application of two-dimensional(2D)materials.The weak van der Waals interaction in 2D materials inspired researchers to explore 2D heterostructures(2DHs)based broadband photodetectors in the far-infrared(IR)and middle-IR regions with high response and high detectivity.This review focuses on the strategy and motivation of designing 2DHs based high-performance IR photodetectors,which provides a wide view of this field and new expectation for advanced photodetectors.First,the photocarriers'generation mechanism and frequently employed device structures are presented.Then,the 2DHs are divided into semimetal/semiconductor 2DHs,semiconductor/semiconductor 2DHs,and multidimensional semi-2DHs;the advantages,motivation,mechanism,recent progress,and outlook are discussed.Finally,the challenges for next-generation photodetectors are described for this rapidly developing field.展开更多
Uncovering the structure evolution and real active species of energy catalytic materials under reaction conditions is important for both understanding structure-activity relationship and constructing electrocatalysts ...Uncovering the structure evolution and real active species of energy catalytic materials under reaction conditions is important for both understanding structure-activity relationship and constructing electrocatalysts for CO2 electroreduction(CO2ER).And integrating CO2ER with an anodic organic transformation to replace the oxygen evolution reaction is highly desirable.Here,In2O3 is selected as the model material to reveal the surface reconstruction under CO2ER condition.In situ and ex situ results reveal that the electrochemical in situ reconstruction of crystalline In2O3 leads to the formation of crystalline-In/amorphous In2O3-x heterostructure(In/In2O3-x).In/In2O3-xacts as the real active phase with Faradaic efficiency of^89.2%for the formate,outperforming In(~67.5%).The improved performance can be ascribed to electron-rich In rectified by Schottky effect of In2O3-xheterostructure.Impressively,formate and high-value octanenitrile can be simultaneously achieved by integrating CO2ER with octylamine oxidation in an In2O3-x||Ni2P two-electrode electrolyzer.展开更多
Two-dimensional(2D)nanomaterials are categorized as a new class of microwave absorption(MA)materials owing to their high specific surface area and peculiar electronic properties.In this study,2D WS2-reduced graphene o...Two-dimensional(2D)nanomaterials are categorized as a new class of microwave absorption(MA)materials owing to their high specific surface area and peculiar electronic properties.In this study,2D WS2-reduced graphene oxide(WS2-rGO)heterostructure nanosheets were synthesized via a facile hydrothermal process;moreover,their dielectric and MA properties were reported for the first time.Remarkably,the maximum reflection loss(RL)of the sample-wax composites containing 40 wt% WS2-rGO was-41.5 dB at a thickness of 2.7 mm;furthermore,the bandwidth where RL<-10 dB can reach up to 13.62 GHz(4.38-18 GHz).Synergistic mechanisms derived from the interfacial dielectric coupling and multiple-interface scattering after hybridization of WS2 with rGO were discussed to explain the drastically enhanced microwave absorption performance.The results indicate these lightweight WS2-rGO nanosheets to be potential materials for practical electromagnetic wave-absorbing applications.展开更多
Metal sulfide based materials as photocatalysts for energy conversion are essential to produce value-added chemical fuels,but their intrinsically slow carrier dynamics and low activity are yet to be resolved.Herein,we...Metal sulfide based materials as photocatalysts for energy conversion are essential to produce value-added chemical fuels,but their intrinsically slow carrier dynamics and low activity are yet to be resolved.Herein,we developed a unique heterogeneously nanostructured ZnIn_(2)S_(4)-CdS heterostructure that involves zero-dimensional(0D)CdS quantum dots uniformly confined on three-dimensional(3D)ZnIn_(2)S_(4)nanoflowers,which achieves an excellent catalytic performance of CO_(2) photoconversion under visible-light irradiation.The obtained hierarchical heterostructure can significantly enhance the light harvesting,shorten the migration distance of carriers,and obviously accelerate the transport of electrons.As evidenced by the ultrafast transient absorption spectroscopy,the formed interface can effectively facilitate charge separation and transport.This work opens up a new avenue to carefully design the elaborate heterostructures for achieving optimal charge separation efficiency by lowering interfacial kinetic barriers and energy losses at the interface.展开更多
基金The authors acknowledge financial support from National Science Funds for Creative Research Groups of China(No.61421002)the National Natural Science Foundation of China(No.61501092,61734003,61521001,61861166001),Key Laboratory of Advanced Photonic and Electronic Materials,Collaborative Innovation Center of Solid-State Lighting and Energy-Saving Electronics.
文摘Two-dimensional(2D)materials are intensively attractive for fabricating high sensitive photodetectors in terms of atomically thin flexible and ultrafast charge transport feature.Due to their atomically thin body,designing high performance detector requires new physical mechanisms and device structures.In this review,we classify design strategies and device structures into four categories depending on their physical mechanisms(photovoltaic effect,photoconductive effect,photothermoelectric effect or photobolometric effect,and surface plasma-wave-assisted effect),and summarize the device performances.Finally,future prospects and development direction for 2D material photodetectors are described.Those design strategies descriptions about photoelectronic detector provide a reference for high responsivity and fast response speed photodetector at broadband sensing in the future.
基金supported by the National Basic Research Program of China (Grant 2012CB937500)the National Natural Science Foundation of China (Grants 11422219, 11227202, 11372217, 11272232)+1 种基金the Program for New Century Excellent Talents in University (Grant NCET-13)China Scholarship Council (201308120092)
文摘Si-based multilayer structures are widely used in current microelectronics. During their preparation, some inhomogeneous residual stress is induced, resulting in competition between interface mismatching and surface energy and even leading to structure failure. This work presents a methodological study on the measurement of residual stress in a multi-layer semiconductor heterostructure. Scanning electron microscopy（SEM）, micro-Raman spectroscopy（MRS）, and transmission electron microscopy（TEM） were applied to measure the geometric parameters of the multilayer structure. The relationship between the Raman spectrum and the stress/strain on the [100] and [110] crystal orientations was determined to enable surface and crosssection residual stress analyses, respectively. Based on the Raman mapping results, the distribution of residual stress along the depth of the multi-layer heterostructure was successfully obtained.
基金the National Natural Science Foundation of China(Nos.61874109,51525202,61674140,61574054,51672076,61804177)the Foundation for Innovative Research Groups of NSFC(Grant 21521063).
文摘A high-performance and broadband heterojunction photodetector has been successfully fabricated.The heterostructure device is based on a uniform and pinhole-free perovskite film constructed on top of a single-crystal germanium layer.The perovskite/germanium photodetector shows enhanced performance and a broad spectrum compared with the single-material-based device.The photon response properties are characterized in detail from the visible to near-infrared spectrum.At an optical fibre communication wavelength of 1550 nm,the heterojunction device exhibits the highest responsivity of 1.4 A/W.The performance is promoted because of an antireflection perovskite coating,the thickness of which is optimized to 150 nm at the telecommunication band.At a visible light wavelength of 680 nm,the device shows outstanding responsivity and detectivity of 228 A/W and 1.6×10^(10) Jones,respectively.These excellent properties arise from the photoconductive gain boost in the heterostructure device.The presented heterojunction photodetector provides a competitive approach for wide-spectrum photodetection from visible to optical communication areas.Based on the distinguished capacity of light detection and harvesting from the visible to near-infrared spectrum,the designed germanium/perovskite heterostructure configuration is believed to provide new building blocks for novel optoelectronic devices.
文摘以硝酸铜为前驱体,不采用任何模板,通过逐步水热法合成了花状Cu2O/Cu复合纳米材料.用扫描电镜(SEM)、X射线衍射(XRD)和紫外-可见漫反射光谱(DRS)对样品进行表征.结果表明,花状纳米Cu2O/Cu材料是由长为300-500nm,宽为30-70nm的带状花瓣构成,在可见光区域有很强的吸收.复合材料中Cu的含量可以通过反应时间进行调控.对染料Procion Red MX-5B(PR)的可见光催化降解,Cu能明显提高Cu2O的光催化性能.当Cu质量分数为27%-71%时,复合材料Cu2O/Cu的催化活性明显高于单相Cu2O.与立方体形貌的Cu2O/Cu复合材料相比,花状纳米Cu2O/Cu复合材料对染料PR有更高的催化降解性能.且该复合材料有较高的循环回收利用率.
基金funded by Australian Research Council discovery project DP140103041Future Fellowship FT160100205
文摘Two-dimensional(2D) materials have attracted extensive interest due to their excellent electrical, thermal,mechanical, and optical properties. Graphene has been one of the most explored 2D materials. However, its zero band gap has limited its applications in electronic devices. Transition metal dichalcogenide(TMDC), another kind of 2D material,has a nonzero direct band gap(same charge carrier momentum in valence and conduction band) at monolayer state,promising for the efficient switching devices(e.g., field-effect transistors). This review mainly focuses on the recent advances in charge carrier mobility and the challenges to achieve high mobility in the electronic devices based on 2DTMDC materials and also includes an introduction of 2D materials along with the synthesis techniques. Finally, this review describes the possible methodology and future prospective to enhance the charge carrier mobility for electronic devices.
基金supported by the National Natural Science Foundation of China(Grant Nos.51722204,91421110,51802145)the National Key Basic Research Program of China(Grant No.2014CB931702)+3 种基金the Sichuan Provincial Fund for Distinguished Young Academic and Technology Leaders(Grant No.2014JQ0011)the Science and Technology Support Program of Sichuan Province(Grant No.2018RZ0042,2016RZ0033,2018RZ0082)the Natural Science Foundation of Guangdong Province(2018A030310225)China Postdoctoral Science Foundation(Grant No.2018M643443).
文摘It is a rapidly developed subject in expanding the fundamental properties and application of two-dimensional(2D)materials.The weak van der Waals interaction in 2D materials inspired researchers to explore 2D heterostructures(2DHs)based broadband photodetectors in the far-infrared(IR)and middle-IR regions with high response and high detectivity.This review focuses on the strategy and motivation of designing 2DHs based high-performance IR photodetectors,which provides a wide view of this field and new expectation for advanced photodetectors.First,the photocarriers'generation mechanism and frequently employed device structures are presented.Then,the 2DHs are divided into semimetal/semiconductor 2DHs,semiconductor/semiconductor 2DHs,and multidimensional semi-2DHs;the advantages,motivation,mechanism,recent progress,and outlook are discussed.Finally,the challenges for next-generation photodetectors are described for this rapidly developing field.
基金the National Natural Science Foundation of China (21871206 and 21701122)。
文摘Uncovering the structure evolution and real active species of energy catalytic materials under reaction conditions is important for both understanding structure-activity relationship and constructing electrocatalysts for CO2 electroreduction(CO2ER).And integrating CO2ER with an anodic organic transformation to replace the oxygen evolution reaction is highly desirable.Here,In2O3 is selected as the model material to reveal the surface reconstruction under CO2ER condition.In situ and ex situ results reveal that the electrochemical in situ reconstruction of crystalline In2O3 leads to the formation of crystalline-In/amorphous In2O3-x heterostructure(In/In2O3-x).In/In2O3-xacts as the real active phase with Faradaic efficiency of^89.2%for the formate,outperforming In(~67.5%).The improved performance can be ascribed to electron-rich In rectified by Schottky effect of In2O3-xheterostructure.Impressively,formate and high-value octanenitrile can be simultaneously achieved by integrating CO2ER with octylamine oxidation in an In2O3-x||Ni2P two-electrode electrolyzer.
基金financially supported by the National Natural Science Foundation of China (Nos. 51272110, 51772160, and 51771123)the Shenzhen Peacock Innovation Project (No. KQJSCX20170327151307811)+1 种基金the support of China Scholarship Council (No. 201506100018)the START project of Japan Science and Technology Agency (JST)
文摘Two-dimensional(2D)nanomaterials are categorized as a new class of microwave absorption(MA)materials owing to their high specific surface area and peculiar electronic properties.In this study,2D WS2-reduced graphene oxide(WS2-rGO)heterostructure nanosheets were synthesized via a facile hydrothermal process;moreover,their dielectric and MA properties were reported for the first time.Remarkably,the maximum reflection loss(RL)of the sample-wax composites containing 40 wt% WS2-rGO was-41.5 dB at a thickness of 2.7 mm;furthermore,the bandwidth where RL<-10 dB can reach up to 13.62 GHz(4.38-18 GHz).Synergistic mechanisms derived from the interfacial dielectric coupling and multiple-interface scattering after hybridization of WS2 with rGO were discussed to explain the drastically enhanced microwave absorption performance.The results indicate these lightweight WS2-rGO nanosheets to be potential materials for practical electromagnetic wave-absorbing applications.
基金the National Natural Science Foundation of China(Nos.21573211,21633007,21671180)the National Key R&D Program of China(Nos.2016YFA0200602,2017YFA0208300,2017YFA0700104,2018YFA0208702)the Anhui Initiative in Quantum Information Technologies(No.AHY090200).We also thank the funding support from the CAS Fujian Institute of Innovation.
文摘Metal sulfide based materials as photocatalysts for energy conversion are essential to produce value-added chemical fuels,but their intrinsically slow carrier dynamics and low activity are yet to be resolved.Herein,we developed a unique heterogeneously nanostructured ZnIn_(2)S_(4)-CdS heterostructure that involves zero-dimensional(0D)CdS quantum dots uniformly confined on three-dimensional(3D)ZnIn_(2)S_(4)nanoflowers,which achieves an excellent catalytic performance of CO_(2) photoconversion under visible-light irradiation.The obtained hierarchical heterostructure can significantly enhance the light harvesting,shorten the migration distance of carriers,and obviously accelerate the transport of electrons.As evidenced by the ultrafast transient absorption spectroscopy,the formed interface can effectively facilitate charge separation and transport.This work opens up a new avenue to carefully design the elaborate heterostructures for achieving optimal charge separation efficiency by lowering interfacial kinetic barriers and energy losses at the interface.
