采用高纯半导体碳纳米管薄膜和石墨烯构建复合结构光探测器,研究其光电响应特性。结果表明,在光照下,顶层石墨烯中的光生载流子通过碳纳米管与石墨烯之间薄的非晶硅层,隧穿至底层的碳纳米管薄膜中,在非晶硅层两侧分别富集电子和空穴,形...采用高纯半导体碳纳米管薄膜和石墨烯构建复合结构光探测器,研究其光电响应特性。结果表明,在光照下,顶层石墨烯中的光生载流子通过碳纳米管与石墨烯之间薄的非晶硅层,隧穿至底层的碳纳米管薄膜中,在非晶硅层两侧分别富集电子和空穴,形成光致栅压(Photogating),有效地改变了碳纳米管薄膜晶体管的电流。器件在可见光(633 nm)条件下得到响应度为83 m A/W,并在近红外波段范围内仍保持好的光响应特性。由于石墨烯具有宽谱光吸收特性,半导体碳纳米管薄膜晶体管具有小的暗电流,碳纳米管–石墨烯复合光探测器发挥了两种材料的优势,为今后高性能宽谱光电探测器的制备奠定了基础。展开更多
Hybrid organic-inorganic perovskites have been demonstrated as promising candidates for broadband-responsive photodetectors. It is critical to develop perovskite-based photodetectors with excellent photodetection capa...Hybrid organic-inorganic perovskites have been demonstrated as promising candidates for broadband-responsive photodetectors. It is critical to develop perovskite-based photodetectors with excellent photodetection capability and facile fabrication processes for practical application. Herein, we designed and fabricated, for the first time, a hybrid photodetector consisting of electrospun ZnO nanofibers and perovskites. Compared to pristine ZnO or perovskite, the hybrid photodetector showed increased on-off ratio, faster response speed, and higher responsivity and detectivity. The performance of the hybrid devices was significantly enhanced by using quasi-aligned ZnO nanofiber arrays instead of disordered nanofibers, which provide efficient charge transfer between the perovskite and ZnO, shorter transmission paths, and reduced carrier loss at cross-junctions of nanofibers. Our results provide a new and promising route to integrate inorganic functional materials with perovskite for high-performance and low-cost photodetectors.展开更多
In the last decade,optoelectronic devices based on organic-inorganic hybrid perovskite(OIHP)materials,which have unique advantages of direct bandgap,large absorption coefficient,low density of defects,long charge carr...In the last decade,optoelectronic devices based on organic-inorganic hybrid perovskite(OIHP)materials,which have unique advantages of direct bandgap,large absorption coefficient,low density of defects,long charge carrier lifetime,diffusion length,and solution processability,have traveled with traditional inorganic semiconductor devices.The state-of-the-art OIHP photodetectors have contributed a comparable performance with Si and III-V compound semiconductor based photodetectors.Large amount of efforts have been focused on improving sensitivity,broadening detection spectra,enlarging linear dynamic range.However,few reports emphasized the important parameter of response speed.In this review,we summarize the progress and applications of OIHP photodetectors with fast response.Based on photovoltaic and photoconductive-type OIHP photodetectors,the working principle and key factors on determining response speed are systematically mentioned.Then,the research progress of response speed,which is composed of resistance-capacitance(RC)time constant and charge carrier transit time is discussed in detail.Subsequently,considering the intrinsic flexibility of perovskite materials,we briefly discuss the flexible photodetectors.Finally,an outlook and potential rules for designing fast-response OIHP photodetectors are further proposed.展开更多
Methylammonium lead halide perovskites have been reported to be promising candidates for high-performance photodetectors. However, self-powered broadband ultraviolet-visible-near infrared （UV-Vis-NIR） photodetection...Methylammonium lead halide perovskites have been reported to be promising candidates for high-performance photodetectors. However, self-powered broadband ultraviolet-visible-near infrared （UV-Vis-NIR） photodetection with high responsivity is difficult to achieve in these materials. Here, we demonstrate, for the first time, a novel trilayer hybrid photodetector made by combining an n-type Si wafer, TiO2 interlayer and perovskite film. By precisely controlling the thickness of the TiO2 layer, enhanced separation and reduced recombination of carriers at the Si-perovskite interface are obtained. As a result, perovskite film, when combined with a low-bandgap Si, extends the wavelength range of photo response to 1,150 nm, along with improved on/off ratio, responsivity, and specific detectivity, when compared to pristine perovskite. Results obtained in this work are comparable or even better than those reported for perovskite-based UV-Vis-NIR photodetectors. In particular, the hybrid photodetectors can operate in a self- powered mode. The mechanism of enhancement has been explored and it is found that the increased separation and reduced recombination of photogenerated carriers at the junction interface leads to the improved performance.展开更多
Gallium antimonide(GaSb)-based nanostructures have been reported via various vapor-phase synthetic routes while there is not a report on the growth of GaSb nanostructures via a complete one-step solution-phase synthet...Gallium antimonide(GaSb)-based nanostructures have been reported via various vapor-phase synthetic routes while there is not a report on the growth of GaSb nanostructures via a complete one-step solution-phase synthetic strategy.Herein we report the design and synthesis of tadpole-like Ga/GaSb nanostructures by a one-step solution-phase synthetic route typically from the precursors of commercial triphenyl antimony(Sb(Ph)_(3))and trimethylaminogallium(Ga(NMe_(2))_(3))at 260°C in 1-octadecene.The GaSb nanocrystals are grown based on a solution–liquid–solid(SLS)mechanism with zinc blende phase,and their size and shape can be controlled in the procedures via manipulating the reaction conditions.Meanwhile,the tadpole-like Ga/GaSb nanostructures can be applied for the fabrication of a GaSb/Si nanostructured heterojunction-like photodetector over silicon wafer,which demonstrates excellent photoresponse and detection performances from wavelength of 405 to 1,064 nm with high photoresponding rate.Typically,the photodetector exhibits a high responsivity of 18.9 A·W^(−1),a superior detectivity of 1.1×10^(13)Jones,and an ultrafast response speed of 44 ns.The present work provides a new strategy to group III–V antimonide-based semiconducting nanostructures that are capable for the fabrication of photodetector with broadband,high-detectivity,and high-speed photodetecting performances.展开更多
文摘采用高纯半导体碳纳米管薄膜和石墨烯构建复合结构光探测器,研究其光电响应特性。结果表明,在光照下,顶层石墨烯中的光生载流子通过碳纳米管与石墨烯之间薄的非晶硅层,隧穿至底层的碳纳米管薄膜中,在非晶硅层两侧分别富集电子和空穴,形成光致栅压(Photogating),有效地改变了碳纳米管薄膜晶体管的电流。器件在可见光(633 nm)条件下得到响应度为83 m A/W,并在近红外波段范围内仍保持好的光响应特性。由于石墨烯具有宽谱光吸收特性,半导体碳纳米管薄膜晶体管具有小的暗电流,碳纳米管–石墨烯复合光探测器发挥了两种材料的优势,为今后高性能宽谱光电探测器的制备奠定了基础。
基金We acknowledge the support from the National Natural Science Foundation of China （Nos. 51422206, 51372159, and 51502184）, 1000 Youth Talents Plan, 333 High-level Talents Cultivation Project of Jiangsu Province, Six Talents Peak Project of Jiangsu Province, Distinguished Young Scholars Foundation by Jiangsu Science and Technology Committee （No. BK20140009）, Natural Science Foundation of Jiangsu Province （No. BK20150331）, and Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions （PAPD）.
文摘Hybrid organic-inorganic perovskites have been demonstrated as promising candidates for broadband-responsive photodetectors. It is critical to develop perovskite-based photodetectors with excellent photodetection capability and facile fabrication processes for practical application. Herein, we designed and fabricated, for the first time, a hybrid photodetector consisting of electrospun ZnO nanofibers and perovskites. Compared to pristine ZnO or perovskite, the hybrid photodetector showed increased on-off ratio, faster response speed, and higher responsivity and detectivity. The performance of the hybrid devices was significantly enhanced by using quasi-aligned ZnO nanofiber arrays instead of disordered nanofibers, which provide efficient charge transfer between the perovskite and ZnO, shorter transmission paths, and reduced carrier loss at cross-junctions of nanofibers. Our results provide a new and promising route to integrate inorganic functional materials with perovskite for high-performance and low-cost photodetectors.
基金The authors are grateful to National Natural Science Foundation of China(61875072)International Cooperation and Exchange Project of People's Government of Jilin Province(20170414002GH,20180414001GH)for their supports to this work.
文摘In the last decade,optoelectronic devices based on organic-inorganic hybrid perovskite(OIHP)materials,which have unique advantages of direct bandgap,large absorption coefficient,low density of defects,long charge carrier lifetime,diffusion length,and solution processability,have traveled with traditional inorganic semiconductor devices.The state-of-the-art OIHP photodetectors have contributed a comparable performance with Si and III-V compound semiconductor based photodetectors.Large amount of efforts have been focused on improving sensitivity,broadening detection spectra,enlarging linear dynamic range.However,few reports emphasized the important parameter of response speed.In this review,we summarize the progress and applications of OIHP photodetectors with fast response.Based on photovoltaic and photoconductive-type OIHP photodetectors,the working principle and key factors on determining response speed are systematically mentioned.Then,the research progress of response speed,which is composed of resistance-capacitance(RC)time constant and charge carrier transit time is discussed in detail.Subsequently,considering the intrinsic flexibility of perovskite materials,we briefly discuss the flexible photodetectors.Finally,an outlook and potential rules for designing fast-response OIHP photodetectors are further proposed.
基金This research was supported by the National Natural Science Foundation of China （Nos. 51672026, 51422206, 51372020, and 51372159）, the National Key Research and Development Program of China （No. 2016YFA0202701）, the Major National Scientific Research Projects （No. 2013CB932602）, 1000 Youth Talents Plan, 333 High-level Talents Cultivation Project of Jiangsu Province, Six Talents Peak Project of Jiangsu Province, Distinguished Young Scholars Foundation by Jiangsu Science and Technology Committee （No. BK20140009）, and Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions （PAPD）.
文摘Methylammonium lead halide perovskites have been reported to be promising candidates for high-performance photodetectors. However, self-powered broadband ultraviolet-visible-near infrared （UV-Vis-NIR） photodetection with high responsivity is difficult to achieve in these materials. Here, we demonstrate, for the first time, a novel trilayer hybrid photodetector made by combining an n-type Si wafer, TiO2 interlayer and perovskite film. By precisely controlling the thickness of the TiO2 layer, enhanced separation and reduced recombination of carriers at the Si-perovskite interface are obtained. As a result, perovskite film, when combined with a low-bandgap Si, extends the wavelength range of photo response to 1,150 nm, along with improved on/off ratio, responsivity, and specific detectivity, when compared to pristine perovskite. Results obtained in this work are comparable or even better than those reported for perovskite-based UV-Vis-NIR photodetectors. In particular, the hybrid photodetectors can operate in a self- powered mode. The mechanism of enhancement has been explored and it is found that the increased separation and reduced recombination of photogenerated carriers at the junction interface leads to the improved performance.
基金supported by the National Natural Science Foundation of China(Nos.U1932150 and 21571166)Anhui Provincial Natural Science Foundation(No.1908085QB72).
文摘Gallium antimonide(GaSb)-based nanostructures have been reported via various vapor-phase synthetic routes while there is not a report on the growth of GaSb nanostructures via a complete one-step solution-phase synthetic strategy.Herein we report the design and synthesis of tadpole-like Ga/GaSb nanostructures by a one-step solution-phase synthetic route typically from the precursors of commercial triphenyl antimony(Sb(Ph)_(3))and trimethylaminogallium(Ga(NMe_(2))_(3))at 260°C in 1-octadecene.The GaSb nanocrystals are grown based on a solution–liquid–solid(SLS)mechanism with zinc blende phase,and their size and shape can be controlled in the procedures via manipulating the reaction conditions.Meanwhile,the tadpole-like Ga/GaSb nanostructures can be applied for the fabrication of a GaSb/Si nanostructured heterojunction-like photodetector over silicon wafer,which demonstrates excellent photoresponse and detection performances from wavelength of 405 to 1,064 nm with high photoresponding rate.Typically,the photodetector exhibits a high responsivity of 18.9 A·W^(−1),a superior detectivity of 1.1×10^(13)Jones,and an ultrafast response speed of 44 ns.The present work provides a new strategy to group III–V antimonide-based semiconducting nanostructures that are capable for the fabrication of photodetector with broadband,high-detectivity,and high-speed photodetecting performances.
基金the International Cooperation Foundation of China (2015DFR10700)the National Natural Science Foundation of China (51403203) for the support of this researchthe support of the Russian Ministry of Education and Science state assignment (3.3197.2017/ПЧ)
文摘有机-无机杂化钙钛矿材料具有载流子迁移率高、扩散长度长、暗电流密度低、吸收边缘锋利等优点,因而成为用于光电探测的理想材料.但是,相对较小的带隙(1.6 eV)限制了这些材料在近红外区的光子捕获效率.本研究中,我们利用碘甲胺和铅-锡二元钙钛矿作为探测器的光吸收层,导电聚合物和富勒烯作为空穴和电子传输层,铟锡氧化物和铝作为阳极和阴极制备了光电探测器件.实验结果表明,当锡的含量达到30%时,探测器的光谱响应拓宽到1000 nm.此外,我们制备的探测器的光谱响应度达到0.39 A W^(-1),归一化探测率达到7×10^(12)Jones.器件的外量子效率在350到900 nm范围内,均超过50%,在550 nm处取得最大值,超过80%.
基金Acknowledgements This work was supported partially by the National Natural Science Foundation of China （Grant Nos. 61422510, 11374263 and 61431166001 ）, the Doctoral Fund of Ministry of Education of China （No. 20120101110094）, the Fundamental Research Funds for the Central Universities,
