Two-dimensional (2D) van der Waals (vdWs) metal-semiconductor heterostructures with atomically sharp interface and matched work functions have recently attracted great attention due to their unique electronic and opto...Two-dimensional (2D) van der Waals (vdWs) metal-semiconductor heterostructures with atomically sharp interface and matched work functions have recently attracted great attention due to their unique electronic and optoelectronic properties. Here we report the vapor phase epitaxial growth of large-scale vertical Sb/WSe2 metal-semiconductor vdWs heterostructures with uniform stacking orientation. Compared with the growth on S1O2/S1 substrate, the thick ness of Sb nan osheet on WSe2 can be reduced effectively to mono layer. We con struct Sb-WSe2-Au asymmetric electrodes photodiode based on the Sb/WSe2 heterostructures. Electrical transport measurements indicate that the photodiode show obvious rectifying effect. Optoelectronic characterizations show prominent photoresponse with a high photoresposivity of 364 mA/W, a fast response time of less than 8 ms, a large open-circuit voltage of 0.27 V and a maximum electrical power output of 0.11 nW. The direct growth of high-quality metal-semiconductor vdWs heterostructures may open up new realms in 2D functional electronics and optoelectronics.展开更多
The mixed-dimensional integration of two-dimensional (2D) materials with non-2D materials can give rise to prominent advances in performance or function.To date,the mixed-dimensional one-dimensional (1D)/2D heterostru...The mixed-dimensional integration of two-dimensional (2D) materials with non-2D materials can give rise to prominent advances in performance or function.To date,the mixed-dimensional one-dimensional (1D)/2D heterostructures have been fabricated using various physical assembly approaches.However,direct epitaxial growth method which has notable advantages in preparing large-scale products and obtaining perfect interfaces is rarely investigated.Herein,we demonstrate for the first time the direct synthesis of the 1D/2D mixed-dimensional heterostructures by sequential vapor-phase growth of Sb2Se3 nanowires on WS2 monolayers.X-ray diffraction (XRD) pattern and Raman spectrum confirm the composition of the Sb2Se3/NS2 heterostructures.Transmission electron microscope (TEM) measurement demonstrates high quality of the heterostructures.Electrical transport characterization reveals that Sb2Se3 nanowire exhibits p-type characteristic and that WS2 monolayer exhibits n-type behavior,and that the p-n diode from 1D/2D mixed-dimensional Sb2Se3/WS2 heterostructure possesses obvious current rectification behavior.Optoelectronic measurements of the heterostructures show apparent photovoltaic response with an open-circuit voltage of 0.19 V,photoresponsivity of 1.51 A/W (Vds =5 V) and fast response time of less than 8 ms.The van der Waals epitaxial growth mode of Sb2Se3 nanowires on WS2 monolayers is verified by stripping the Sb2Se3 nanowire from the heterostructures using tape.Together,the direct van der Waals epitaxy opens a facile pathway to 1D/2D mixed-dimensional heterostructures for functional electronic and optoelectronic devices.展开更多
Heterostructures combined by different individual two-dimensional(2D)materials are essential building blocks to realize unique electronic,optoelectronic properties and multifunctional applications.To date,the direct g...Heterostructures combined by different individual two-dimensional(2D)materials are essential building blocks to realize unique electronic,optoelectronic properties and multifunctional applications.To date,the direct growth of 2D/2D atomic van der Waals heterostructures(vdWHs)have been extensively investigated.However,the heterostructures from 2D inorganic molecular crystals and atomic crystals have been rarely reported.Here we report two-step direct epitaxial growth of the inorganic molecular-atomic Sb2O3/WS2 vdWHs.The thickness of Sb2O3 nanosheets on WS2 nanosheets can be tuned by variable growth temperatures.Oriented growth behavior of Sb2O3 on WS2 was determined through statistics.Optical images,Raman spectra,Raman mappings and selected-area electron diffraction(SAED),etc.,reveal that Sb2O3/WS2 heterostructures are vertically stacked with high crystal quality.Electrical transport measurements demonstrate that the heterotransistors based on the heterostructures possess high current on/off ratio of 5 × 10^5,obvious gate-tunable and current rectification output characteristics.Optoelectronic characterizations show that the heterostructures have a clear photoresponse with high responsivity of 16.4 AW.The growth of vdWHs from 2D inorganic molecular-atomic crystals may open up new opportunities in 2D functional electronics and optoelectronics.展开更多
基金the National Natural Science Foundation of China (Nos. 61804050 and 51872086)the Double First-Class Initiative of Hunan University (No. 531109100004)the Fundamental Research Funds of the Central Universities (Nos. 531107051078 and 531107051055).
文摘Two-dimensional (2D) van der Waals (vdWs) metal-semiconductor heterostructures with atomically sharp interface and matched work functions have recently attracted great attention due to their unique electronic and optoelectronic properties. Here we report the vapor phase epitaxial growth of large-scale vertical Sb/WSe2 metal-semiconductor vdWs heterostructures with uniform stacking orientation. Compared with the growth on S1O2/S1 substrate, the thick ness of Sb nan osheet on WSe2 can be reduced effectively to mono layer. We con struct Sb-WSe2-Au asymmetric electrodes photodiode based on the Sb/WSe2 heterostructures. Electrical transport measurements indicate that the photodiode show obvious rectifying effect. Optoelectronic characterizations show prominent photoresponse with a high photoresposivity of 364 mA/W, a fast response time of less than 8 ms, a large open-circuit voltage of 0.27 V and a maximum electrical power output of 0.11 nW. The direct growth of high-quality metal-semiconductor vdWs heterostructures may open up new realms in 2D functional electronics and optoelectronics.
基金the Fundamental Research Funds of the Central Universities (No.531107051078)the Double First-Class University Initiative of Hunan University (No.531109100004). We also acknowledge the support from the National Natural Science Foundation of China (No.751214296)+1 种基金Hunan Key Laboratory of Two-Dimensional Materials (No.801200005)Strategic Priority Research Program of Chinese Academy of Science (No.XDB30000000).
文摘The mixed-dimensional integration of two-dimensional (2D) materials with non-2D materials can give rise to prominent advances in performance or function.To date,the mixed-dimensional one-dimensional (1D)/2D heterostructures have been fabricated using various physical assembly approaches.However,direct epitaxial growth method which has notable advantages in preparing large-scale products and obtaining perfect interfaces is rarely investigated.Herein,we demonstrate for the first time the direct synthesis of the 1D/2D mixed-dimensional heterostructures by sequential vapor-phase growth of Sb2Se3 nanowires on WS2 monolayers.X-ray diffraction (XRD) pattern and Raman spectrum confirm the composition of the Sb2Se3/NS2 heterostructures.Transmission electron microscope (TEM) measurement demonstrates high quality of the heterostructures.Electrical transport characterization reveals that Sb2Se3 nanowire exhibits p-type characteristic and that WS2 monolayer exhibits n-type behavior,and that the p-n diode from 1D/2D mixed-dimensional Sb2Se3/WS2 heterostructure possesses obvious current rectification behavior.Optoelectronic measurements of the heterostructures show apparent photovoltaic response with an open-circuit voltage of 0.19 V,photoresponsivity of 1.51 A/W (Vds =5 V) and fast response time of less than 8 ms.The van der Waals epitaxial growth mode of Sb2Se3 nanowires on WS2 monolayers is verified by stripping the Sb2Se3 nanowire from the heterostructures using tape.Together,the direct van der Waals epitaxy opens a facile pathway to 1D/2D mixed-dimensional heterostructures for functional electronic and optoelectronic devices.
基金We acknowledge the financial support from the Fundamental Research Funds of the Central Universities(No.531118010112)the Double First-Class University Initiative of Hunan University(No.531109100004)+2 种基金We also acknowledge the support from the National Natural Science Foundation of China(No.751214296)Hunan Key Laboratory of Two-Dimensional Materials(No.801200005)Strategic Priority Research Program of Chinese Academy of Science(No.XDB30000000).
文摘Heterostructures combined by different individual two-dimensional(2D)materials are essential building blocks to realize unique electronic,optoelectronic properties and multifunctional applications.To date,the direct growth of 2D/2D atomic van der Waals heterostructures(vdWHs)have been extensively investigated.However,the heterostructures from 2D inorganic molecular crystals and atomic crystals have been rarely reported.Here we report two-step direct epitaxial growth of the inorganic molecular-atomic Sb2O3/WS2 vdWHs.The thickness of Sb2O3 nanosheets on WS2 nanosheets can be tuned by variable growth temperatures.Oriented growth behavior of Sb2O3 on WS2 was determined through statistics.Optical images,Raman spectra,Raman mappings and selected-area electron diffraction(SAED),etc.,reveal that Sb2O3/WS2 heterostructures are vertically stacked with high crystal quality.Electrical transport measurements demonstrate that the heterotransistors based on the heterostructures possess high current on/off ratio of 5 × 10^5,obvious gate-tunable and current rectification output characteristics.Optoelectronic characterizations show that the heterostructures have a clear photoresponse with high responsivity of 16.4 AW.The growth of vdWHs from 2D inorganic molecular-atomic crystals may open up new opportunities in 2D functional electronics and optoelectronics.
