Nanowire-based photovoltaic devices have the advantages over planar devices in light absorption and charge transport and collection.Recently,a new strategy relying on type-Ⅱ band alignment has been proposed to facili...Nanowire-based photovoltaic devices have the advantages over planar devices in light absorption and charge transport and collection.Recently,a new strategy relying on type-Ⅱ band alignment has been proposed to facilitate efficient charge separation in core/shell nanowire solar cells.This paper reviews the type-Ⅱ heterojunction solar cells based on core/shell nanowire arrays,and specifically focuses on the progress of theoretical design and fabrication of type-Ⅱ Zn O/Zn Se core/shell nanowire-based solar cells.A strong photoresponse associated with the type-Ⅱ interfacial transition exhibits a threshold of 1.6 e V,which demonstrates the feasibility and great potential for exploring all-inorganic versions of type-Ⅱ heterojunction solar cells using wide bandgap semiconductors.Future prospects in this area are also outlooked.展开更多
Solar-driven water splitting is a promising alternative to industrial hydrogen production.This study reports an elaborate design and synthesis of the integration of cadmium sulfi de(CdS)quantum dots and cuprous sulfi ...Solar-driven water splitting is a promising alternative to industrial hydrogen production.This study reports an elaborate design and synthesis of the integration of cadmium sulfi de(CdS)quantum dots and cuprous sulfi de(Cu_(2)S)nanosheets as three-dimensional(3D)hollow octahedral Cu_(2)S/CdS p-n heterostructured architectures by a versatile template and one-pot sulfi dation strategy.3D hierarchical hollow nanostructures can strengthen multiple refl ections of solar light and provide a large specifi c surface area and abundant reaction sites for photocatalytic water splitting.Owing to the construction of the p-n heterostructure as an ideal catalytic model with highly matched band alignment at Cu_(2)S/CdS interfaces,the emerging internal electric fi eld can facilitate the space separation and transfer of photoexcited charges between CdS and Cu_(2)S and also enhance charge dynamics and prolong charge lifetimes.Notably,the unique hollow Cu_(2)S/CdS architectures deliver a largely enhanced visible-light-driven hydrogen generation rate of 4.76 mmol/(g·h),which is nearly 8.5 and 476 times larger than that of pristine CdS and Cu_(2)S catalysts,respectively.This work not only paves the way for the rational design and fabrication of hollow photocatalysts but also clarifi es the crucial role of unique heterostructure in photocatalysis for solar energy conversion.展开更多
Photocatalytic conversion of CO_(2) into small-molecule chemical feedstocks can meet the growing demand for energy and alleviate the global warming. Herein, a p-n ZnO@CDs@Co_(3)O_(4) heterojunction with sandwich struc...Photocatalytic conversion of CO_(2) into small-molecule chemical feedstocks can meet the growing demand for energy and alleviate the global warming. Herein, a p-n ZnO@CDs@Co_(3)O_(4) heterojunction with sandwich structure was constructed by calcination method of self-assembled ZIF-8@CDs@ZIF-67. The ZnO@CDs@Co_(3)O_(4) with well-defined interfacial structure exhibited the significantly enhanced photocatalytic CO_(2) reduction activity, and the optimal catalyst indicated the(CO + CH_(4)) evolution rate of 214.53μmol g^(-1)h^(-1) under simulated solar light, which was superior to ZnO, Co_(3)O_(4) and binary ZnO@Co_(3)O_(4).The internal cavity, exposed active sites, multiple interfaces and constructed p-n heterojunction can facilitate the light harvesting and photoexcited electron transfer. Besides, after introduction of CDs placed in the middle layer between ZnO and Co_(3)O_(4), CDs with excellent photoelectric property further promoted charge separation and migration. This work represents an appealing strategy to construct well-defined photocatalysts for boosting CO_(2) photoreduction.展开更多
Formaldehyde is a common atmospheric pollutant produced in industrial production and daily life.However,the traditional semiconductor formaldehyde gas sensor cannot work at room temperature,which limits its practical ...Formaldehyde is a common atmospheric pollutant produced in industrial production and daily life.However,the traditional semiconductor formaldehyde gas sensor cannot work at room temperature,which limits its practical application.Therefore,developing high-performance gas sensors for rapidly and accurately detecting formaldehyde at room temperature is an important topic.In this study,Ti_(3)C_(2)Tx/SnO_(2)heterostructures were constructed,which could selectively detect formaldehyde at room temperature with a response value of 29.16%(10×10^(-6)).In addition,the sensor shows a remarkable theoretical detection limit of 5.09×10^(-9)and good longterm stability.Density functional theory(DFT)simulations reveal that SnO_(2)nano spheres provide the majority of adsorption sites that strongly interact with formaldehyde.Meanwhile,Ti_(3)C_(2)T_(x)acting as a conductive layer facilitates the transfer of charge carriers so that they show a sensing response to formaldehyde at room temperature.Moreover,the formation of p-n heterostructures between SnO_(2)and Ti_(3)C_(2)T_(x)boosts the Schottky barrier at the interface,which is the critical factor in enhancing the sensing properties by turning the Schottky barrier upon introducing formaldehyde gas.This perspective is expected to provide instructive guidance for utilizing MXene/metal oxide nanocomposites to improve the gas sensing performance at room temperature.展开更多
Van der Waals semiconductor heterostructures(VSHs)composed of two or more two-dimensional(2D)materials with different band gaps exhibit huge potential for exploiting high-performance multifunctional devices.The applic...Van der Waals semiconductor heterostructures(VSHs)composed of two or more two-dimensional(2D)materials with different band gaps exhibit huge potential for exploiting high-performance multifunctional devices.The application of 2D VSHs in atomically thin devices highly depends on the control of their carrier type and density.Herein,on the basis of comprehensive first-principles calculations,we report a new strategy to manipulate the doping polarity and carrier density in a class of 2D VSHs consisting of atomically thin transition metal dichalcogenides(TMDs)andα-In_(2)X_(3)(X=S,Se)ferroelectrics via switchable polarization field.Our calculated results indicate that the band bending of In_(2)X_(3)layer driven by the FE polarization can be utilized for engineering the band alignment and doping polarity of TMD/In_(2)X_(3)VSHs,which enables us to control their carrier density and type of the VSHs by the orientation and magnitude of local FE polarization field.Inspired by these findings,we demonstrate that doping-free p–n junctions achieved in MoTe2/In2Se3 VSHs exhibit high carrier density(1013–1014 cm–2),and the inversion of the VHSs from n–p junctions to p–i–n junctions has been realized by the polarization switching from upward to downward states.This work provides a nonvolatile and nondestructive doping strategy for obtaining programmable p–n van der Waals(vdW)junctions and opens the possibilities for self-powered and multifunctional device applications.展开更多
We have studied the transport property of the composites （La0.83Sr0.17 MnO3）1-x（ITO）x [ITO=（In2O3）0.95 （SNO2）0.05], which were fabricated by mechanically mixing La0.83Sr0.17MnO3 and ITO grains. A giant positiv...We have studied the transport property of the composites （La0.83Sr0.17 MnO3）1-x（ITO）x [ITO=（In2O3）0.95 （SNO2）0.05], which were fabricated by mechanically mixing La0.83Sr0.17MnO3 and ITO grains. A giant positive magnetoresistance （PMR） has been observed above the Curie temperature Tc for samples with x around 0.40, in addition to the negative magnetoresistanee related to spin-dependent interracial tunnelling below To. For （La0.83Sr0.17MnO3）0.6（ITO）0.4, the magnetoresistive ratio for the PMR can reach 39.3% under a magnetic field H=2.24×10^5A/m. Theoretical analysis suggests that the magnetic-field-induced broadening of the p-n barrier between both kinds of grains and the density of the p-n heterostructures should be responsible for the PMR behaviour.展开更多
Tin dioxide is important gas sensor material and has wide applications in the detection of toxic gases and volatile organic compounds.Here,we synthesized a 3D laminated structural CuO/SnO2 material possessing p-n hete...Tin dioxide is important gas sensor material and has wide applications in the detection of toxic gases and volatile organic compounds.Here,we synthesized a 3D laminated structural CuO/SnO2 material possessing p-n heterostructures.The morphology and structure were characterized by XRD,SEM,TEM and XPS techniques and the sensing properties were investigated for the detection of triethylamine(TEA).The results indicate that 3D laminated CuO/SnO2 material,assembled by lamellae consisting of ordered nanoparticles,exhibit an enhanced sensing performance compared with SnO2,and notably,CuO/SnO2 with size less than 1μm has obvious high selectivity in the detection of 100 ppm TEA.Particularly,it has a high response and stability to 1 and 5 ppm TEA(S is 8 and 33),and that is higher than SnO2 material,suggesting 3D laminated CuO/SnO2 is an effective ca ndidate material served as sensor platform to detect low-concentration amines.展开更多
To drive photoelectrochemical water splitting on porous BiVO4 photoanode,we herein prepared a carnationlike CuS powder by hydrothermal method and then loaded it onto BiVO4 photoelectrode.Expectedly,the CuS/BiVO4 compo...To drive photoelectrochemical water splitting on porous BiVO4 photoanode,we herein prepared a carnationlike CuS powder by hydrothermal method and then loaded it onto BiVO4 photoelectrode.Expectedly,the CuS/BiVO4 composite not only presents a higher photocurrent response value at 1.23 V versus RHE(reversible hydrogen electrode)than pure BiVO4 electrode under visible light irradiation,but also exhibits an excellent photoelectrochemical hydrogen production activity in comparison with either the BiVO4 or the CuS.The high ameliorated performance of CuS/BiVO4 composite may be due to the strong absorption of visible light and an effective abatement in combination of carriers.These results demonstrate an effective potential approach to design and construct efficient photoelectrochemical(PEC)systems.展开更多
基金supported by "973" Program (No.2012CB619301 and 2011CB925600)the National Natural Science Foundations of China (No.61227009,61106008,61106118,90921002,and 60827004)+1 种基金the Natural Science Foundations of Fujian Provincethe fundamental research funds for the central universities (No.2011121042 and 2011121026)
文摘Nanowire-based photovoltaic devices have the advantages over planar devices in light absorption and charge transport and collection.Recently,a new strategy relying on type-Ⅱ band alignment has been proposed to facilitate efficient charge separation in core/shell nanowire solar cells.This paper reviews the type-Ⅱ heterojunction solar cells based on core/shell nanowire arrays,and specifically focuses on the progress of theoretical design and fabrication of type-Ⅱ Zn O/Zn Se core/shell nanowire-based solar cells.A strong photoresponse associated with the type-Ⅱ interfacial transition exhibits a threshold of 1.6 e V,which demonstrates the feasibility and great potential for exploring all-inorganic versions of type-Ⅱ heterojunction solar cells using wide bandgap semiconductors.Future prospects in this area are also outlooked.
基金National Natural Science Foundation of China(No.21972015)Young Top Talents Pro-ject of Liaoning Province(No.XLYC1907147)+2 种基金Joint Research Fund Liaoning-Shenyang National Laboratory for Materials Science(No.2019JH3/30100003)the Fundamental Research Funds for the Central Universities(No.DUT20TD06)the Swedish Research Council,and the K&A Wallenberg Foundation.
文摘Solar-driven water splitting is a promising alternative to industrial hydrogen production.This study reports an elaborate design and synthesis of the integration of cadmium sulfi de(CdS)quantum dots and cuprous sulfi de(Cu_(2)S)nanosheets as three-dimensional(3D)hollow octahedral Cu_(2)S/CdS p-n heterostructured architectures by a versatile template and one-pot sulfi dation strategy.3D hierarchical hollow nanostructures can strengthen multiple refl ections of solar light and provide a large specifi c surface area and abundant reaction sites for photocatalytic water splitting.Owing to the construction of the p-n heterostructure as an ideal catalytic model with highly matched band alignment at Cu_(2)S/CdS interfaces,the emerging internal electric fi eld can facilitate the space separation and transfer of photoexcited charges between CdS and Cu_(2)S and also enhance charge dynamics and prolong charge lifetimes.Notably,the unique hollow Cu_(2)S/CdS architectures deliver a largely enhanced visible-light-driven hydrogen generation rate of 4.76 mmol/(g·h),which is nearly 8.5 and 476 times larger than that of pristine CdS and Cu_(2)S catalysts,respectively.This work not only paves the way for the rational design and fabrication of hollow photocatalysts but also clarifi es the crucial role of unique heterostructure in photocatalysis for solar energy conversion.
基金supported by the National Natural Science Foundation of China (Nos.51725204, 21771132, 51972216, 52041202)Qinglan Project Foundation of Jiangsu Province,Zhejiang Province Key Research and Development Project (No.2023 C01191)。
文摘Photocatalytic conversion of CO_(2) into small-molecule chemical feedstocks can meet the growing demand for energy and alleviate the global warming. Herein, a p-n ZnO@CDs@Co_(3)O_(4) heterojunction with sandwich structure was constructed by calcination method of self-assembled ZIF-8@CDs@ZIF-67. The ZnO@CDs@Co_(3)O_(4) with well-defined interfacial structure exhibited the significantly enhanced photocatalytic CO_(2) reduction activity, and the optimal catalyst indicated the(CO + CH_(4)) evolution rate of 214.53μmol g^(-1)h^(-1) under simulated solar light, which was superior to ZnO, Co_(3)O_(4) and binary ZnO@Co_(3)O_(4).The internal cavity, exposed active sites, multiple interfaces and constructed p-n heterojunction can facilitate the light harvesting and photoexcited electron transfer. Besides, after introduction of CDs placed in the middle layer between ZnO and Co_(3)O_(4), CDs with excellent photoelectric property further promoted charge separation and migration. This work represents an appealing strategy to construct well-defined photocatalysts for boosting CO_(2) photoreduction.
基金financially supported by the National Natural Science Foundation of China(No.61973223)the Innovative Talents in Colleges and Universities in Liaoning Province(No.2020389)+3 种基金Liao Ning Revitalization Talents Program(No.XLYC2007051)Liaoning Educational Department Foundation(No.LJKMZ20220762)the Natural Science Foundation of Liaoning Province(No.2021-MS-257)the Young and Middle-aged Scientific and Technological Innovation Talents of Shenyang Science and Technology Bureau(No.RC200352)。
文摘Formaldehyde is a common atmospheric pollutant produced in industrial production and daily life.However,the traditional semiconductor formaldehyde gas sensor cannot work at room temperature,which limits its practical application.Therefore,developing high-performance gas sensors for rapidly and accurately detecting formaldehyde at room temperature is an important topic.In this study,Ti_(3)C_(2)Tx/SnO_(2)heterostructures were constructed,which could selectively detect formaldehyde at room temperature with a response value of 29.16%(10×10^(-6)).In addition,the sensor shows a remarkable theoretical detection limit of 5.09×10^(-9)and good longterm stability.Density functional theory(DFT)simulations reveal that SnO_(2)nano spheres provide the majority of adsorption sites that strongly interact with formaldehyde.Meanwhile,Ti_(3)C_(2)T_(x)acting as a conductive layer facilitates the transfer of charge carriers so that they show a sensing response to formaldehyde at room temperature.Moreover,the formation of p-n heterostructures between SnO_(2)and Ti_(3)C_(2)T_(x)boosts the Schottky barrier at the interface,which is the critical factor in enhancing the sensing properties by turning the Schottky barrier upon introducing formaldehyde gas.This perspective is expected to provide instructive guidance for utilizing MXene/metal oxide nanocomposites to improve the gas sensing performance at room temperature.
基金supported by the National Natural Science Foundation of China(Grant No.62174151 and 61775201)the Fund of Zhejiang Provincial Natural Science Foundation of China(Grant No.LZ22F040003 and LY22A040002).
文摘Van der Waals semiconductor heterostructures(VSHs)composed of two or more two-dimensional(2D)materials with different band gaps exhibit huge potential for exploiting high-performance multifunctional devices.The application of 2D VSHs in atomically thin devices highly depends on the control of their carrier type and density.Herein,on the basis of comprehensive first-principles calculations,we report a new strategy to manipulate the doping polarity and carrier density in a class of 2D VSHs consisting of atomically thin transition metal dichalcogenides(TMDs)andα-In_(2)X_(3)(X=S,Se)ferroelectrics via switchable polarization field.Our calculated results indicate that the band bending of In_(2)X_(3)layer driven by the FE polarization can be utilized for engineering the band alignment and doping polarity of TMD/In_(2)X_(3)VSHs,which enables us to control their carrier density and type of the VSHs by the orientation and magnitude of local FE polarization field.Inspired by these findings,we demonstrate that doping-free p–n junctions achieved in MoTe2/In2Se3 VSHs exhibit high carrier density(1013–1014 cm–2),and the inversion of the VHSs from n–p junctions to p–i–n junctions has been realized by the polarization switching from upward to downward states.This work provides a nonvolatile and nondestructive doping strategy for obtaining programmable p–n van der Waals(vdW)junctions and opens the possibilities for self-powered and multifunctional device applications.
基金Project supported by the National Natural Science Foundation of China （Grant No 20473038）, the Foundation of High-Tech Project in Jiangsu province, China （Grant No BG-2005401）.
文摘We have studied the transport property of the composites （La0.83Sr0.17 MnO3）1-x（ITO）x [ITO=（In2O3）0.95 （SNO2）0.05], which were fabricated by mechanically mixing La0.83Sr0.17MnO3 and ITO grains. A giant positive magnetoresistance （PMR） has been observed above the Curie temperature Tc for samples with x around 0.40, in addition to the negative magnetoresistanee related to spin-dependent interracial tunnelling below To. For （La0.83Sr0.17MnO3）0.6（ITO）0.4, the magnetoresistive ratio for the PMR can reach 39.3% under a magnetic field H=2.24×10^5A/m. Theoretical analysis suggests that the magnetic-field-induced broadening of the p-n barrier between both kinds of grains and the density of the p-n heterostructures should be responsible for the PMR behaviour.
基金National Natural Science Foundation of China(No.51572185)Natural Science Foundation of Shanxi Province(No.2014011016-4)+4 种基金Key R&D program of Shanxi Province(International Cooperation,No.201903D421079)for the financial supportsupported by Shanxi Province Technology Foundation for Selected Overseas Chinese ScholarResearch Project Supported by Shanxi Scholarship Council of ChinaCollege Student Innovation Program of Shanxi(Nos.2017550,2018081)National College Student Innovation and Entrepreneurship Training Program(No.201910112002)。
文摘Tin dioxide is important gas sensor material and has wide applications in the detection of toxic gases and volatile organic compounds.Here,we synthesized a 3D laminated structural CuO/SnO2 material possessing p-n heterostructures.The morphology and structure were characterized by XRD,SEM,TEM and XPS techniques and the sensing properties were investigated for the detection of triethylamine(TEA).The results indicate that 3D laminated CuO/SnO2 material,assembled by lamellae consisting of ordered nanoparticles,exhibit an enhanced sensing performance compared with SnO2,and notably,CuO/SnO2 with size less than 1μm has obvious high selectivity in the detection of 100 ppm TEA.Particularly,it has a high response and stability to 1 and 5 ppm TEA(S is 8 and 33),and that is higher than SnO2 material,suggesting 3D laminated CuO/SnO2 is an effective ca ndidate material served as sensor platform to detect low-concentration amines.
基金financially supported by the National Natural Science Foundation of China (Nos. 21663027 and 21808189)the Natural Science Foundation of Gansu Province (No. 18JR3RA090)the Opening Project of Key Laboratory of Green Catalysis of Sichuan Institutes of High Education (No. LYJ18205)
文摘To drive photoelectrochemical water splitting on porous BiVO4 photoanode,we herein prepared a carnationlike CuS powder by hydrothermal method and then loaded it onto BiVO4 photoelectrode.Expectedly,the CuS/BiVO4 composite not only presents a higher photocurrent response value at 1.23 V versus RHE(reversible hydrogen electrode)than pure BiVO4 electrode under visible light irradiation,but also exhibits an excellent photoelectrochemical hydrogen production activity in comparison with either the BiVO4 or the CuS.The high ameliorated performance of CuS/BiVO4 composite may be due to the strong absorption of visible light and an effective abatement in combination of carriers.These results demonstrate an effective potential approach to design and construct efficient photoelectrochemical(PEC)systems.
基金This work has been partly supported by the National Basic Research Program of China （973 Program） No. 2011CB922204-2, and the National Natural Science Foundation of China （Nos. 11434010, 11147024, 11247025, 11304306, 11374002, and 61290303）.
