Heterojunction is regarded as a crucial step toward realizing high-performance devices,particularly,forming gradient energy band between heterojunctions benefits self-powered photodetectors.Therefore,in this paper,the...Heterojunction is regarded as a crucial step toward realizing high-performance devices,particularly,forming gradient energy band between heterojunctions benefits self-powered photodetectors.Therefore,in this paper,the synthesis of CsPbI3 nanorods(NRs)and its application as the interfacial layer in high-performance,all-solution-processed self-powered photodetectors are presented.For the bilayer photodetector ITO/ZnO(100 nm)/PbS-TBAI(150 nm)/Au,a responsivity of 3.6 A/W with a specific detectivity of 9.8×10^(12)Jones was obtained under 0.1 mW/cm^(2)white light illumination at zero bias(i.e.in self-powered mode).Meanwhile,the photocurrent was enhanced to an On/Off current ratio of 105 at zero bias with an open circuit voltage of 0.53 V for trilayer photodetector ITO/ZnO(100 nm)/PbSTBAI(150 nm)/CsPbI3(250 nm)/Au,in which the CsPbI3 NRs layer works as the interfacial layer.As a result,a specific detectivity of 4.5×10^(13)Jones with a responsivity of 11.12 A/W was obtained under0.1 mW/cm^(2) white light illumination,as well as the rising/decaying time of 0.57 s/0.41 s with excellent stability and reproducibility upto four weeks in air.The enhanced-performance is ascribed to the mismatch bandgap between PbS-TBAI/CsPbI_(3)interface,which can suppress the carrier recombination and provide efficient transport passages for charge carriers.Thus,it provides a feasible and efficient method for high-performance photodetectors.展开更多
Due to their promising applications in foldable displays,optical communication equipment and environmental monitoring systems,flexible and broadband optoelectronic devices have gained extensive attention in recent yea...Due to their promising applications in foldable displays,optical communication equipment and environmental monitoring systems,flexible and broadband optoelectronic devices have gained extensive attention in recent years.Here,a flexible and broadband photodetector based on CsPbBr_(3)/PbSe quantum dot(QD) heterostructures is firstly presented.The integrated QD heterostructures possess consecutive detection range from ultraviolet(UV) to long-wave length infrared(LW-IR) regions with efficient light absorption and chemical stability,in comparison with the pristine PbSe QDs.Systematic material characterizations reveal the improved exciton dissociation,carrier transport and carrier lifetime of the QD heterostructures.Flexible photodetector Ag/CsPbBr_(3)/PbSe/Ag demonstrate a high responsivity of 7.17 A/W with a specific detectivity of 8.97 × 10^(12) Jones under 25 μW/cm^(2) 365 nm illumination at 5 V.Furthermore,it could maintain 91.2 %(or 94.9 %) of its initial performance even after bending for thousands of times(or exposing in ambient air for 4 weeks).More importantly,its re s ponse time is shortened more than three orders of magnitude as that of pristine PbSe QDs-based photodetectors.Therefore,it provides a feasible and promising method for the next-generation high-performance broadband photodetectors via constructing heterostructures of various QDs.展开更多
AIM:To evaluate the outcomes of pars plana vitrectomy(PPV) without the use of an ocular tamponade in patients having tractional retinal detachment(TRD) secondary to proliferative diabetic retinopathy(PDR).METHODS:It w...AIM:To evaluate the outcomes of pars plana vitrectomy(PPV) without the use of an ocular tamponade in patients having tractional retinal detachment(TRD) secondary to proliferative diabetic retinopathy(PDR).METHODS:It was an interventional study conducted at the Department of Ophthalmology,B.V.Hospital,Bahawalpur,Pakistan,from July 2011 to July 2012.A total of 75 patients(84 eyes) having TRD secondary to PDR were treated by PPV without using an ocular tamponade.All patients included in the study had a tractional retinal detachement secondary to proliferative diabetic retinopathy but didn’t have or develop retinal breaks before or during the study period.The surgical procedure included a PPV combined with the removal of the tractional retinal membranes and the application of endolaser photocoagulation to the retina.The mean follow-up period was 12 months. RESULTS:Successful retinal reattachement was observed in 78 of the operated eyes(92.8%).In these patients,the retina remained attached till the end of the one year follow-up period.Improvement in best corrected visual acuity(BCVA) was seen in 63 eyes(75%).The visual acuity remained unchanged in 9 eyes(10.7%).Mean improvement in BCVA was 2.00 +1.24 at baseline to 1.24+1.22(P【0.05) at the end of the followup period.CONCLUSION:In the absence of the retinal breaks,a TRD secondary to PDR can be successfully treated by pars plana vitrectomy without the use of an ocular tamponade.展开更多
基金partially funded by the project of State Key Laboratory of Transducer Technology(SKT1404)the project of the Key Laboratory of Photoelectronic Imaging Technology and System(2017OEIOF02)Beijing Institute of Technology,Ministry of Education of Chinathe project of the Key R&D projects of the Ministry of Science and Technology(SQ2019YFB220038)。
文摘Heterojunction is regarded as a crucial step toward realizing high-performance devices,particularly,forming gradient energy band between heterojunctions benefits self-powered photodetectors.Therefore,in this paper,the synthesis of CsPbI3 nanorods(NRs)and its application as the interfacial layer in high-performance,all-solution-processed self-powered photodetectors are presented.For the bilayer photodetector ITO/ZnO(100 nm)/PbS-TBAI(150 nm)/Au,a responsivity of 3.6 A/W with a specific detectivity of 9.8×10^(12)Jones was obtained under 0.1 mW/cm^(2)white light illumination at zero bias(i.e.in self-powered mode).Meanwhile,the photocurrent was enhanced to an On/Off current ratio of 105 at zero bias with an open circuit voltage of 0.53 V for trilayer photodetector ITO/ZnO(100 nm)/PbSTBAI(150 nm)/CsPbI3(250 nm)/Au,in which the CsPbI3 NRs layer works as the interfacial layer.As a result,a specific detectivity of 4.5×10^(13)Jones with a responsivity of 11.12 A/W was obtained under0.1 mW/cm^(2) white light illumination,as well as the rising/decaying time of 0.57 s/0.41 s with excellent stability and reproducibility upto four weeks in air.The enhanced-performance is ascribed to the mismatch bandgap between PbS-TBAI/CsPbI_(3)interface,which can suppress the carrier recombination and provide efficient transport passages for charge carriers.Thus,it provides a feasible and efficient method for high-performance photodetectors.
基金partially funded by the Project of State Key Laboratory of Transducer Technology (No. SKT1404)the Fundamental Research Funds for the Central Universities (No. 2020CX02002 and BITBLR2020013)the Key R&D Projects of the Ministry of Science and Technology (No. SQ2019YFB220038)。
文摘Due to their promising applications in foldable displays,optical communication equipment and environmental monitoring systems,flexible and broadband optoelectronic devices have gained extensive attention in recent years.Here,a flexible and broadband photodetector based on CsPbBr_(3)/PbSe quantum dot(QD) heterostructures is firstly presented.The integrated QD heterostructures possess consecutive detection range from ultraviolet(UV) to long-wave length infrared(LW-IR) regions with efficient light absorption and chemical stability,in comparison with the pristine PbSe QDs.Systematic material characterizations reveal the improved exciton dissociation,carrier transport and carrier lifetime of the QD heterostructures.Flexible photodetector Ag/CsPbBr_(3)/PbSe/Ag demonstrate a high responsivity of 7.17 A/W with a specific detectivity of 8.97 × 10^(12) Jones under 25 μW/cm^(2) 365 nm illumination at 5 V.Furthermore,it could maintain 91.2 %(or 94.9 %) of its initial performance even after bending for thousands of times(or exposing in ambient air for 4 weeks).More importantly,its re s ponse time is shortened more than three orders of magnitude as that of pristine PbSe QDs-based photodetectors.Therefore,it provides a feasible and promising method for the next-generation high-performance broadband photodetectors via constructing heterostructures of various QDs.
文摘AIM:To evaluate the outcomes of pars plana vitrectomy(PPV) without the use of an ocular tamponade in patients having tractional retinal detachment(TRD) secondary to proliferative diabetic retinopathy(PDR).METHODS:It was an interventional study conducted at the Department of Ophthalmology,B.V.Hospital,Bahawalpur,Pakistan,from July 2011 to July 2012.A total of 75 patients(84 eyes) having TRD secondary to PDR were treated by PPV without using an ocular tamponade.All patients included in the study had a tractional retinal detachement secondary to proliferative diabetic retinopathy but didn’t have or develop retinal breaks before or during the study period.The surgical procedure included a PPV combined with the removal of the tractional retinal membranes and the application of endolaser photocoagulation to the retina.The mean follow-up period was 12 months. RESULTS:Successful retinal reattachement was observed in 78 of the operated eyes(92.8%).In these patients,the retina remained attached till the end of the one year follow-up period.Improvement in best corrected visual acuity(BCVA) was seen in 63 eyes(75%).The visual acuity remained unchanged in 9 eyes(10.7%).Mean improvement in BCVA was 2.00 +1.24 at baseline to 1.24+1.22(P【0.05) at the end of the followup period.CONCLUSION:In the absence of the retinal breaks,a TRD secondary to PDR can be successfully treated by pars plana vitrectomy without the use of an ocular tamponade.
