Low-dimensional hybrid lead-halide perovskites with broadband white-light emission upon near-UV excitation have attracted immense scientific interest due to their potential application for the next generation of solid...Low-dimensional hybrid lead-halide perovskites with broadband white-light emission upon near-UV excitation have attracted immense scientific interest due to their potential application for the next generation of solid-state lighting as well as scintillators for radiation detection.Recently,broadband emission material is mostly reported in structural distorted perovskites.However,it is still unclear how to generate structural distortion in low-dimensional perovskites.展开更多
Here,we show that flexible perovskite solar cells(PSCs)with high operational stability and power conversion efficiency(PCE)approaching 20%were achieved by elastic grain boundary(GB)encapsulation.An introduction of tri...Here,we show that flexible perovskite solar cells(PSCs)with high operational stability and power conversion efficiency(PCE)approaching 20%were achieved by elastic grain boundary(GB)encapsulation.An introduction of trimethyltrivinylcyclotrisiloxane(V3D3)and solvent annealing(SA)resulted in an in situ cross-linking reaction between GBs and enlarged grain size that enabled oriented charge-transport properties to be achieved synchronously,leading to reduced sheet resistance with a high fill factor(FF)up to 82.93%in flexible PSCs.展开更多
Surface electronic structure of solid materials plays a critical role in heterogeneous catalysis. However, surface chemical composition of the perovskite oxides is usually dominated by segregated A-site cations and th...Surface electronic structure of solid materials plays a critical role in heterogeneous catalysis. However, surface chemical composition of the perovskite oxides is usually dominated by segregated A-site cations and the amount of oxygen vacancies is relatively low, which seriously restricts their catalytic oxidation property. Here, we prepare perovskite LaxSrl xCO03 ~ （x = 0.3, 0.5, 0.7） with different Sr doping amount and experiment results show that perovskite LSCO with higher content of surface Sr possesses more oxy- gen vacancies and better catalytic activity. On this basis, we develop a new experimental strategy to cre- ate more surface oxygen vacancies to promote their CO catalytic activity. In this method, we use high active hydrogen atoms （BHa-） as reductant to realize surface in-situ chemical composite modification of LaxSrl xCo03 ~s （x = 0.3, 0.5, 0.7）, which causes their surface reconstruction （surface Sr enrichment）. The regulation mainly focuses on the atomic layer level without damaging their bulk phase structure. Different from traditional high temperature annealing under reducing atmosphere, this method is high-efficiency, green and controllable. Furthermore, we study the surface reconstruction process and demonstrated that it is atomic layer engineering on the surface of LaxSr1-xCoO3-δ （x = 0.3, 0.5, 0.7） by X-ray photoelectron spectroscopy （XPS） and X-ray absorption fine structure （XAFS）. Our experiment results also show that these samples treated by this method exhibit superior activity for CO oxidation compared with original samples.展开更多
基金supported by the National Natural Science Foundation of China(no.21875089).Q.D.conceived the idea,supervised the project,and conducted the initial experimentX.L.conducted most of the experiments and characterizations+3 种基金Z.Y.,C.G.,and H.L.contributed to materials design and synthesisM.H.,C.W.,and Y.S.contributed to the test of TRPLB.L.contributed to the single-crystal data and structure refinementsQ.D.and X.L wrote the paper.All authors have given approval to the final version of the manuscript.
文摘Low-dimensional hybrid lead-halide perovskites with broadband white-light emission upon near-UV excitation have attracted immense scientific interest due to their potential application for the next generation of solid-state lighting as well as scintillators for radiation detection.Recently,broadband emission material is mostly reported in structural distorted perovskites.However,it is still unclear how to generate structural distortion in low-dimensional perovskites.
文摘Here,we show that flexible perovskite solar cells(PSCs)with high operational stability and power conversion efficiency(PCE)approaching 20%were achieved by elastic grain boundary(GB)encapsulation.An introduction of trimethyltrivinylcyclotrisiloxane(V3D3)and solvent annealing(SA)resulted in an in situ cross-linking reaction between GBs and enlarged grain size that enabled oriented charge-transport properties to be achieved synchronously,leading to reduced sheet resistance with a high fill factor(FF)up to 82.93%in flexible PSCs.
基金supported by the National Natural Science Foundation of China (21671076,21427802 and 21131002)
文摘Surface electronic structure of solid materials plays a critical role in heterogeneous catalysis. However, surface chemical composition of the perovskite oxides is usually dominated by segregated A-site cations and the amount of oxygen vacancies is relatively low, which seriously restricts their catalytic oxidation property. Here, we prepare perovskite LaxSrl xCO03 ~ （x = 0.3, 0.5, 0.7） with different Sr doping amount and experiment results show that perovskite LSCO with higher content of surface Sr possesses more oxy- gen vacancies and better catalytic activity. On this basis, we develop a new experimental strategy to cre- ate more surface oxygen vacancies to promote their CO catalytic activity. In this method, we use high active hydrogen atoms （BHa-） as reductant to realize surface in-situ chemical composite modification of LaxSrl xCo03 ~s （x = 0.3, 0.5, 0.7）, which causes their surface reconstruction （surface Sr enrichment）. The regulation mainly focuses on the atomic layer level without damaging their bulk phase structure. Different from traditional high temperature annealing under reducing atmosphere, this method is high-efficiency, green and controllable. Furthermore, we study the surface reconstruction process and demonstrated that it is atomic layer engineering on the surface of LaxSr1-xCoO3-δ （x = 0.3, 0.5, 0.7） by X-ray photoelectron spectroscopy （XPS） and X-ray absorption fine structure （XAFS）. Our experiment results also show that these samples treated by this method exhibit superior activity for CO oxidation compared with original samples.
