The interface defects between the electron transport layer(ETL)and the perovskite layer,as well as the low ultraviolet(UV)light utilization rate of the perovskite absorption layer,pose significant challenges for the c...The interface defects between the electron transport layer(ETL)and the perovskite layer,as well as the low ultraviolet(UV)light utilization rate of the perovskite absorption layer,pose significant challenges for the commercialization of perovskite solar cells(PSCs).To address this issue,this paper proposes an innovative multifunctional interface modulation strategy by introducing aggregation-induced emission(AIE)molecule 5-[4-[1,2,2-tri[4-(3,5-dicarboxyphenyl)phenyl]ethylene]phenyl]benzene-1,3-dicarboxylic acid(H_(8)ETTB)at the SnO_(2)ETL/perovskite interface.Firstly,the interaction of H_(8)ETTB with the SnO_(2)surface,facilitated by its carboxyl groups,is effective in passivating surface defects caused by noncoord inated Sn and O vacancies.This interaction enhances the conductivity of the SnO_(2)film and adjusts energy levels,leading to enhanced charge carrier transport.Simultaneously,H_(8)ETTB can passivate noncoord inated Pb^(2+)ions at the perovskite interface,promoting perovskite crystallization and reducing the interface energy barrier,resulting in a perovskite film with low defects and high crystalline quality.More importantly,the H_(8)ETTB molecule,can convert UV light into light absorbable by the perovskite,thereby reducing damage caused by UV light and improving the device's utilization of UV.Consequently,the champion PSC based on SnO_(2)-H_(8)ETTB achieves an impressing efficiency of 23.32%and significantly improved photostability compared with the control device after continuous exposure to intense UV radiation.In addition,the Cs_(0.05)(FA_(0.95)MA_(0.05))_(0.95)Pb(I_(0.95)Br_(0.05))_(3)based device can achieve maximum efficiency of 24.01%,demonstrating the effectiveness and universality of this strategy.Overall,this innovative interface bridging strategy effectively tackles interface defects and low UV light utilization in PSCs,presenting a promising approach for achieving highly efficient and stable PSCs.展开更多
Nowadays, astronomy has entered the era of Time-Domain Astronomy, and the study of the time-varying light curves of various types of objects is of great significance in revealing the physical properties and evolutiona...Nowadays, astronomy has entered the era of Time-Domain Astronomy, and the study of the time-varying light curves of various types of objects is of great significance in revealing the physical properties and evolutionary history of celestial bodies. The Ground-based Wide Angle Cameras telescope, on which this paper is based, has observed more than 10 million light curves, and the detection of anomalies in the light curves can be used to rapidly detect transient rare phenomena such as microgravity lensing events from the massive data. However, the traditional statistically based anomaly detection methods cannot realize the fast processing of massive data. In this paper, we propose a Discrete Wavelet(DW)-Gate Recurrent Unit-Attention(GRU-Attention) light curve warning model. Wavelet transform has good effect on data noise reduction processing and feature extraction, which can provide richer and more stable input features for a neural network, and the neural network can provide more flexible and powerful output model for wavelet transform. Comparison experiments show an average improvement of 61% compared to the previous pure long-short-term memory unit(LSTM) model, and an average improvement of 53.5% compared to the previous GRU model. The efficiency and accuracy of anomaly detection in previous paper work are not good enough, the method proposed in this paper possesses higher efficiency and accuracy,which incorporates the Attention mechanism to find out the key parts of the light curve that determine the anomalies. These parts are assigned higher weights, and in the actual anomaly detection, the star is detected with83.35% anomalies on average, and the DW-GRU-Attention model is compared with the DW-LSTM model, and the detection result f1 is improved by 5.75% on average, while having less training time, thus providing valuable information and guidance for astronomical observation and research.展开更多
Traditional operating range prediction methods assume that the atmospheric radiances in a target path and a background path are equal. But they are different in a real-world environment. To solve this problem,the infl...Traditional operating range prediction methods assume that the atmospheric radiances in a target path and a background path are equal. But they are different in a real-world environment. To solve this problem,the influence of atmospheric radiance on operating range prediction is analyzed in this paper. Range estimation model in thermal imaging based on background radiation( REBR) is proposed. Infrared image radiometric calibration is used to calculate the background radiation of a system entrance pupil. The result shows that,compared with traditional operating range prediction methods,the REBR method is more suitable for the actual atmospheric transmission process and the physical process of infrared imaging.展开更多
Broadband photodetection(PD)covering the deep ultraviolet to near-infrared(200–1000 nm)range is significant and desirable for various optoelectronic designs.Herein,we employ ultraviolet(UV)luminescent concentrators(L...Broadband photodetection(PD)covering the deep ultraviolet to near-infrared(200–1000 nm)range is significant and desirable for various optoelectronic designs.Herein,we employ ultraviolet(UV)luminescent concentrators(LC),iodinebased perovskite quantum dots(PQDs),and organic bulk heterojunction(BHJ)as the UV,visible,and near-infrared(NIR)photosensitive layers,respectively,to construct a broadband heterojunction PD.Firstly,experimental and theoretical results reveal that optoelectronic properties and stability of CsPbI3 PQDs are significantly improved through Er3+doping,owing to the reduced defect density,improved charge mobility,increased formation energy,tolerance factor,etc.The narrow bandgap of CsPbI3:Er3+PQDs serves as a visible photosensitive layer of PD.Secondly,considering the matchable energy bandgap,the BHJ(BTP-4Cl:PBDB-TF)is selected as to NIR absorption layer to fabricate the hybrid structure with CsPbI3:Er3+PQDs.Thirdly,UV LC converts the UV light(200–400 nm)to visible light(400–700 nm),which is further absorbed by CsPbI3:Er3+PQDs.In contrast with other perovskites PDs and commercial Si PDs,our PD presents a relatively wide response range and high detectivity especially in UV and NIR regions(two orders of magnitude increase that of commercial Si PDs).Furthermore,the PD also demonstrates significantly enhanced air-and UV-stability,and the photocurrent of the device maintains 81.5%of the original one after 5000 cycles.This work highlights a new attempt for designing broadband PDs,which has application potential in optoelectronic devices.展开更多
基金finically supported by the National Natural Science Foundation of China(62350054,12374379,12174152,12304462)the Foundation of National Key Laboratory(***202302011)。
文摘The interface defects between the electron transport layer(ETL)and the perovskite layer,as well as the low ultraviolet(UV)light utilization rate of the perovskite absorption layer,pose significant challenges for the commercialization of perovskite solar cells(PSCs).To address this issue,this paper proposes an innovative multifunctional interface modulation strategy by introducing aggregation-induced emission(AIE)molecule 5-[4-[1,2,2-tri[4-(3,5-dicarboxyphenyl)phenyl]ethylene]phenyl]benzene-1,3-dicarboxylic acid(H_(8)ETTB)at the SnO_(2)ETL/perovskite interface.Firstly,the interaction of H_(8)ETTB with the SnO_(2)surface,facilitated by its carboxyl groups,is effective in passivating surface defects caused by noncoord inated Sn and O vacancies.This interaction enhances the conductivity of the SnO_(2)film and adjusts energy levels,leading to enhanced charge carrier transport.Simultaneously,H_(8)ETTB can passivate noncoord inated Pb^(2+)ions at the perovskite interface,promoting perovskite crystallization and reducing the interface energy barrier,resulting in a perovskite film with low defects and high crystalline quality.More importantly,the H_(8)ETTB molecule,can convert UV light into light absorbable by the perovskite,thereby reducing damage caused by UV light and improving the device's utilization of UV.Consequently,the champion PSC based on SnO_(2)-H_(8)ETTB achieves an impressing efficiency of 23.32%and significantly improved photostability compared with the control device after continuous exposure to intense UV radiation.In addition,the Cs_(0.05)(FA_(0.95)MA_(0.05))_(0.95)Pb(I_(0.95)Br_(0.05))_(3)based device can achieve maximum efficiency of 24.01%,demonstrating the effectiveness and universality of this strategy.Overall,this innovative interface bridging strategy effectively tackles interface defects and low UV light utilization in PSCs,presenting a promising approach for achieving highly efficient and stable PSCs.
基金supported by the National Key Research and Development Program of China(grant id:2022YFF0711500)the National Natural Science Foundation of China(grant id:11803022 and grant id:1227307712273077)。
文摘Nowadays, astronomy has entered the era of Time-Domain Astronomy, and the study of the time-varying light curves of various types of objects is of great significance in revealing the physical properties and evolutionary history of celestial bodies. The Ground-based Wide Angle Cameras telescope, on which this paper is based, has observed more than 10 million light curves, and the detection of anomalies in the light curves can be used to rapidly detect transient rare phenomena such as microgravity lensing events from the massive data. However, the traditional statistically based anomaly detection methods cannot realize the fast processing of massive data. In this paper, we propose a Discrete Wavelet(DW)-Gate Recurrent Unit-Attention(GRU-Attention) light curve warning model. Wavelet transform has good effect on data noise reduction processing and feature extraction, which can provide richer and more stable input features for a neural network, and the neural network can provide more flexible and powerful output model for wavelet transform. Comparison experiments show an average improvement of 61% compared to the previous pure long-short-term memory unit(LSTM) model, and an average improvement of 53.5% compared to the previous GRU model. The efficiency and accuracy of anomaly detection in previous paper work are not good enough, the method proposed in this paper possesses higher efficiency and accuracy,which incorporates the Attention mechanism to find out the key parts of the light curve that determine the anomalies. These parts are assigned higher weights, and in the actual anomaly detection, the star is detected with83.35% anomalies on average, and the DW-GRU-Attention model is compared with the DW-LSTM model, and the detection result f1 is improved by 5.75% on average, while having less training time, thus providing valuable information and guidance for astronomical observation and research.
文摘Traditional operating range prediction methods assume that the atmospheric radiances in a target path and a background path are equal. But they are different in a real-world environment. To solve this problem,the influence of atmospheric radiance on operating range prediction is analyzed in this paper. Range estimation model in thermal imaging based on background radiation( REBR) is proposed. Infrared image radiometric calibration is used to calculate the background radiation of a system entrance pupil. The result shows that,compared with traditional operating range prediction methods,the REBR method is more suitable for the actual atmospheric transmission process and the physical process of infrared imaging.
基金supported by the National Natural Science Foundation of China(Grant Nos.62175025,11974143,and 11974142)the Key Program of NSFCGuangdong Joint Funds of China(U1801253)+1 种基金Outstanding Young Talents of Dalian(2021RJ07)the Natural Science Foundation of Jilin Province(20200201252JC).
文摘Broadband photodetection(PD)covering the deep ultraviolet to near-infrared(200–1000 nm)range is significant and desirable for various optoelectronic designs.Herein,we employ ultraviolet(UV)luminescent concentrators(LC),iodinebased perovskite quantum dots(PQDs),and organic bulk heterojunction(BHJ)as the UV,visible,and near-infrared(NIR)photosensitive layers,respectively,to construct a broadband heterojunction PD.Firstly,experimental and theoretical results reveal that optoelectronic properties and stability of CsPbI3 PQDs are significantly improved through Er3+doping,owing to the reduced defect density,improved charge mobility,increased formation energy,tolerance factor,etc.The narrow bandgap of CsPbI3:Er3+PQDs serves as a visible photosensitive layer of PD.Secondly,considering the matchable energy bandgap,the BHJ(BTP-4Cl:PBDB-TF)is selected as to NIR absorption layer to fabricate the hybrid structure with CsPbI3:Er3+PQDs.Thirdly,UV LC converts the UV light(200–400 nm)to visible light(400–700 nm),which is further absorbed by CsPbI3:Er3+PQDs.In contrast with other perovskites PDs and commercial Si PDs,our PD presents a relatively wide response range and high detectivity especially in UV and NIR regions(two orders of magnitude increase that of commercial Si PDs).Furthermore,the PD also demonstrates significantly enhanced air-and UV-stability,and the photocurrent of the device maintains 81.5%of the original one after 5000 cycles.This work highlights a new attempt for designing broadband PDs,which has application potential in optoelectronic devices.