Omnidirectional photodetectors attract enormous attention due to their prominent roles in optical tracking systems and omnidirectional cameras.However,it is still a challenge for the construction of high-performance o...Omnidirectional photodetectors attract enormous attention due to their prominent roles in optical tracking systems and omnidirectional cameras.However,it is still a challenge for the construction of high-performance omnidirectional photodetectors where the incident light can be effectively absorbed in multiple directions and the photo-generated carriers can be effectively collected.Here,a high-performance omnidirectional self-powered photodetector based on the CsSnBr_(3)/indium tin oxide(ITO)heterostructure film was designed and demonstrated.The as-fabricated photodetector exhibited an excellent self-powered photodetection performance,showing responsivity and detectivity up to 35.1 mA/W and 1.82×10^(10) Jones,respectively,along with the smart rise/decay response time of 4 ms/9 ms.Benefitting from the excellent photoelectric properties of the CsSnBr_(3) film as well as the ability of the CsSnBr_(3)/ITO heterostructure to efficiently separate and collect photo-generated carriers,the as-fabricated photodetector also exhibited an excellent omnidirectional self-powered photodetection performance.All the results have certified that this work finds an efficient way to realize high-performance omnidirectional self-powered photodetectors.展开更多
Major elements such as Fe,Ti,Mg,Al,Ca and Si play very important roles in understanding the origin and evolution of the Moon.Previous maps of these major elements derived from orbital data are based on mosaic images o...Major elements such as Fe,Ti,Mg,Al,Ca and Si play very important roles in understanding the origin and evolution of the Moon.Previous maps of these major elements derived from orbital data are based on mosaic images or low-resolution gamma-ray data.The hue variations and gaps among orbital boundaries in the mosaic images are not conducive to geological studies.This paper aims to produce seamless and homogenous distribution maps of major elements using the single-exposure image of the whole lunar disk obtained by China’s high-resolution geostationary satellite,Gaofen-4,with a spatial resolution of500 m.The elemental contents of soil samples returned by Apollo and Luna missions are regarded as ground truth,and are correlated with the reflectance of the sampling sites extracted from Gaofen-4 data.The final distribution maps of these major oxides are generated with the statistical regression model.With these products,the average contents and proportions of the major elements for maria and highlands were estimated and compared.The results showed that Si O2 and Ti O2 have the highest and lowest fractions in mare and highland areas,respectively.Moreover,the relative concentrations of these elements could serve as indicators of geologic processes,e.g.,the obviously asymmetric distributions of Al2 O3,Ca O and Si O2 around Tycho crater may suggest that Tycho crater was formed by an oblique impact from the southwest direction.展开更多
Biodiversity assessments can often be time- and resource-consuming. Several alternative approaches have been proposed to reduce sampling efforts, including indicator taxa and surrogates. In this study, we examine the ...Biodiversity assessments can often be time- and resource-consuming. Several alternative approaches have been proposed to reduce sampling efforts, including indicator taxa and surrogates. In this study, we examine the reliability of higher taxon surrogates to predict species richness in two experimental rice fields of Fujian Province, southeastern China during 2005 and 2009. Spider samples in transgenic and nontransgenie plots were collected using a suction sampler. Both the genus and family surrogates had significant and positive linear relationships with species richness in the transgenic and nontransgenic rice fields. The rice varieties did not significantly influence the linear relationships. Our findings suggest that higher-taxon surrogacy could be a useful alternative to complete species inventory for risk assessments of transgenic rice.展开更多
Non-layered two-dimensional(2D) lead-free all-inorganic perovskites nanoplates have recently attracted considerable attention in photodetectors;however, the indepth investigation of thickness on photodetection perform...Non-layered two-dimensional(2D) lead-free all-inorganic perovskites nanoplates have recently attracted considerable attention in photodetectors;however, the indepth investigation of thickness on photodetection performance is still lacking. In this work, by constructing the famous metal-semiconductor-metal photodetectors, the photodetection behaviors of thickness-controlled CsSnBr;nanoplates are investigated systematically. Ni electrodes are adopted for ensuring the good ohmic contact behaviors of as-fabricated photodetectors. With the increase in thickness, the photodetection performances improve accordingly, such as photocurrent increases from 0.22 to 19.40 nA, responsivity increases from 72.9 to 4893.7 mA·W^(-1), rise/decay time decreases from 11/35 to 3/10 ms, respectively. Notability, the dark current also increases with the increase in thickness, making the further investigation on the reduction in dark current meaningful.All of the as-fabricated photodetectors are stable, suggesting the careful thickness selection in next-generation high-performance lead-free all-inorganic perovskites photodetectors.展开更多
基金supported by the National Key R&D Program of China under Grant No.2017YFA0305500National Natural Science Foundation of China under Grant No.61904096,Taishan Scholars Program of Shandong Province under Grant No.tsqn201812006+2 种基金Natural Science Foundation of Shandong Province under Grants No.ZR2022JQ05 and No.ZR2022QF025Shandong University Multidisciplinary Research and Innovation Team of Young Scholars under Grant No.2020QNQT015“Outstanding Youth Scholar and Qilu Young Scholar”Programs of Shandong University.
文摘Omnidirectional photodetectors attract enormous attention due to their prominent roles in optical tracking systems and omnidirectional cameras.However,it is still a challenge for the construction of high-performance omnidirectional photodetectors where the incident light can be effectively absorbed in multiple directions and the photo-generated carriers can be effectively collected.Here,a high-performance omnidirectional self-powered photodetector based on the CsSnBr_(3)/indium tin oxide(ITO)heterostructure film was designed and demonstrated.The as-fabricated photodetector exhibited an excellent self-powered photodetection performance,showing responsivity and detectivity up to 35.1 mA/W and 1.82×10^(10) Jones,respectively,along with the smart rise/decay response time of 4 ms/9 ms.Benefitting from the excellent photoelectric properties of the CsSnBr_(3) film as well as the ability of the CsSnBr_(3)/ITO heterostructure to efficiently separate and collect photo-generated carriers,the as-fabricated photodetector also exhibited an excellent omnidirectional self-powered photodetection performance.All the results have certified that this work finds an efficient way to realize high-performance omnidirectional self-powered photodetectors.
基金supported by the National Key R&D Program of China(2018YFB0504700)the National Natural Science Foundation of China(Grant No.42050202)+2 种基金the pre-research project on Civil Aerospace Technologies by CNSA(D020203)the Macao Science and Technology Development Fund(0090/2020/A,0042/2018/A2)Minor Planet Foundation of Purple Mountain Observatory。
文摘Major elements such as Fe,Ti,Mg,Al,Ca and Si play very important roles in understanding the origin and evolution of the Moon.Previous maps of these major elements derived from orbital data are based on mosaic images or low-resolution gamma-ray data.The hue variations and gaps among orbital boundaries in the mosaic images are not conducive to geological studies.This paper aims to produce seamless and homogenous distribution maps of major elements using the single-exposure image of the whole lunar disk obtained by China’s high-resolution geostationary satellite,Gaofen-4,with a spatial resolution of500 m.The elemental contents of soil samples returned by Apollo and Luna missions are regarded as ground truth,and are correlated with the reflectance of the sampling sites extracted from Gaofen-4 data.The final distribution maps of these major oxides are generated with the statistical regression model.With these products,the average contents and proportions of the major elements for maria and highlands were estimated and compared.The results showed that Si O2 and Ti O2 have the highest and lowest fractions in mare and highland areas,respectively.Moreover,the relative concentrations of these elements could serve as indicators of geologic processes,e.g.,the obviously asymmetric distributions of Al2 O3,Ca O and Si O2 around Tycho crater may suggest that Tycho crater was formed by an oblique impact from the southwest direction.
文摘Biodiversity assessments can often be time- and resource-consuming. Several alternative approaches have been proposed to reduce sampling efforts, including indicator taxa and surrogates. In this study, we examine the reliability of higher taxon surrogates to predict species richness in two experimental rice fields of Fujian Province, southeastern China during 2005 and 2009. Spider samples in transgenic and nontransgenie plots were collected using a suction sampler. Both the genus and family surrogates had significant and positive linear relationships with species richness in the transgenic and nontransgenic rice fields. The rice varieties did not significantly influence the linear relationships. Our findings suggest that higher-taxon surrogacy could be a useful alternative to complete species inventory for risk assessments of transgenic rice.
基金the National Key R&D Program of China(No.2017YFA0305500)the National Natural Science Foundation of China(Nos.61904096 and 62104133)+3 种基金Taishan Scholars Program of Shandong Province(No.tsqn201812006)Shandong University Youth Innovation Supporting Program(No.2019KJN020)Shandong University Multidisciplinary Research and Innovation Team of Young Scholars(No.2020QNQT015)‘‘Outstanding Youth Scholar and Qilu Young Scholar’’programs of Shandong University。
文摘Non-layered two-dimensional(2D) lead-free all-inorganic perovskites nanoplates have recently attracted considerable attention in photodetectors;however, the indepth investigation of thickness on photodetection performance is still lacking. In this work, by constructing the famous metal-semiconductor-metal photodetectors, the photodetection behaviors of thickness-controlled CsSnBr;nanoplates are investigated systematically. Ni electrodes are adopted for ensuring the good ohmic contact behaviors of as-fabricated photodetectors. With the increase in thickness, the photodetection performances improve accordingly, such as photocurrent increases from 0.22 to 19.40 nA, responsivity increases from 72.9 to 4893.7 mA·W^(-1), rise/decay time decreases from 11/35 to 3/10 ms, respectively. Notability, the dark current also increases with the increase in thickness, making the further investigation on the reduction in dark current meaningful.All of the as-fabricated photodetectors are stable, suggesting the careful thickness selection in next-generation high-performance lead-free all-inorganic perovskites photodetectors.