Lead(Pb)^(0) and iodine(I)^(0) point defects generated during perovskite solar cell(PSC)fabrication and photoconversion form deep band energy levels as the carriers’recombination centers.These defects not only deteri...Lead(Pb)^(0) and iodine(I)^(0) point defects generated during perovskite solar cell(PSC)fabrication and photoconversion form deep band energy levels as the carriers’recombination centers.These defects not only deteriorate device efficiency,but also facilitate chemical degradation with ion migration,resulting in restricted device lifetime.Herein,we present a novel type of phosphines as the point defects stabilizer for hybrid perovskite solar cells with enhanced performances.Three phosphines with varied side groups of tributyl,trioctyl and triphenyl are exampled as the dopants in perovskite films.The group dependent redox properties were observed in the perovskite film,dependent on their molecular weights and steric hinderances of phosphines.The partially oxidized tributyl phosphine(TBUP)with additional tributyl phosphine oxides(TBPO)is efficient in reduction of lead(Pb)^(0) and iodine(I)^(0) concentrations during the device fabrication and operation.The device with TBUP-TBPO pair showed enhanced power conversion efficiency(PCE)to 20.48% and maintain 91.7% of their initial PCEs after 500 h at 65℃ thermal annealing.Thus,this work presents an efficient route of utilize the phosphine species to reduce point defects in the perovskite film,which promoting further development of novel phosphorous additives with defects stabilization,interface passivation and encapsulation for low-cost solution processed PSCs.展开更多
Knowing the time extension degree of full mortality in phosphine fumigation at low temperature significantly contributes to successful insect pest control,especially for reducing fumigation failure and inhibiting resi...Knowing the time extension degree of full mortality in phosphine fumigation at low temperature significantly contributes to successful insect pest control,especially for reducing fumigation failure and inhibiting resistance development.The comparison ofmortality and lethal time on eggs,larvae,pupae and adults of Cryptolestes ferrugineus(Stephens)was conducted,and the strain with 1043 times of resistance factor to phosphine was assayed during fumigation with 300 mL/m^3 of phosphine concentration at 18,23 and 28℃.The LT50 values to eggs,larvae,pupae and adults of C.ferrugineus at 18℃ were postponed by 2,2,1 and 5 d comparedwith that at 23℃,and 5,4,5 and 7 d compared with that at 28℃,respectively.The LT99 values to eggs,larvae,pupae and adults at 18℃ were 5,1,2 and 7 d longer than that at 23℃,and 6,5,5 and 10 d longer than that at 28℃,respectively.The lethal time of different life stages of the C.ferrugineus strain significantly increased with temperature decreasing.The exposure time of full mortality on pupae at 300 mL/m^3 of phosphine at 18℃ reached 38 d,which was 12 d longer than that of larvae.The order of tolerance of different life stages of C.ferrugineus exposed to 300 mL/m^3 phosphine from high to low was pupae,eggs,adults,larvae at tested temperatures.展开更多
The phosphine-functionalized phosphonium-based ionic liquids(dppm-Q, dppe-Q, dppp-Q and dppb-Q) as the bi-functional ligands enable the efficient one-pot tandem hydroformylationeacetalization. It was found that, in dp...The phosphine-functionalized phosphonium-based ionic liquids(dppm-Q, dppe-Q, dppp-Q and dppb-Q) as the bi-functional ligands enable the efficient one-pot tandem hydroformylationeacetalization. It was found that, in dppm-Q, dppe-Q, dppp-Q and dppb-Q, the incorporated phosphino-fragments were responsible for Rh-catalyzed hydroformylation and the phosphoniums were in charge of the subsequent acetalization as the Lewis acid catalysts. Moreover, the diphosphonium-based ionic liquid of dppb-DQ could be applied as a co-solvent to immobilize the Rh/dppb-Q catalytic system with the advantages of the improved catalytic performance, the available catalyst recyclability, and the wide generality for the substrates.展开更多
The new tetracarbonyl - chromium-triphenyl phosphine complex was synthesized and characterized using ultraviolet(UV)-visible,Fourier transform infrared(FTIR),and nuclear magnetic resonance(NMR) techniques.The ch...The new tetracarbonyl - chromium-triphenyl phosphine complex was synthesized and characterized using ultraviolet(UV)-visible,Fourier transform infrared(FTIR),and nuclear magnetic resonance(NMR) techniques.The characterization results confirm the molecular structure of the new complex.The z-scan measurements were done by diode laser[continuous wave(CW)]to estimate the nonlinear optical parameter(X^3).The results led to calculate three parameters:the groundstate cross sections(σ_g),the excited-state cross sections(σ_(ex)),and thermo-optic coefficient of the new complex.This study indicated that our complex is a suitable for photonic applications.展开更多
基金supported financially by the National Key Research and Development Plan,China(2017YFE0131900)the National Science Foundation of China(NSFC 51672202,21875178)+1 种基金the Technological Innovation Key Project of Hubei Province(2018AAA048)the support the“Chutian Scholar Program”of Hubei Province,China。
文摘Lead(Pb)^(0) and iodine(I)^(0) point defects generated during perovskite solar cell(PSC)fabrication and photoconversion form deep band energy levels as the carriers’recombination centers.These defects not only deteriorate device efficiency,but also facilitate chemical degradation with ion migration,resulting in restricted device lifetime.Herein,we present a novel type of phosphines as the point defects stabilizer for hybrid perovskite solar cells with enhanced performances.Three phosphines with varied side groups of tributyl,trioctyl and triphenyl are exampled as the dopants in perovskite films.The group dependent redox properties were observed in the perovskite film,dependent on their molecular weights and steric hinderances of phosphines.The partially oxidized tributyl phosphine(TBUP)with additional tributyl phosphine oxides(TBPO)is efficient in reduction of lead(Pb)^(0) and iodine(I)^(0) concentrations during the device fabrication and operation.The device with TBUP-TBPO pair showed enhanced power conversion efficiency(PCE)to 20.48% and maintain 91.7% of their initial PCEs after 500 h at 65℃ thermal annealing.Thus,this work presents an efficient route of utilize the phosphine species to reduce point defects in the perovskite film,which promoting further development of novel phosphorous additives with defects stabilization,interface passivation and encapsulation for low-cost solution processed PSCs.
基金This work was supported by National Key Research and Development Program of the 13th Five-Year Plan(No.2017YFC1600800).
文摘Knowing the time extension degree of full mortality in phosphine fumigation at low temperature significantly contributes to successful insect pest control,especially for reducing fumigation failure and inhibiting resistance development.The comparison ofmortality and lethal time on eggs,larvae,pupae and adults of Cryptolestes ferrugineus(Stephens)was conducted,and the strain with 1043 times of resistance factor to phosphine was assayed during fumigation with 300 mL/m^3 of phosphine concentration at 18,23 and 28℃.The LT50 values to eggs,larvae,pupae and adults of C.ferrugineus at 18℃ were postponed by 2,2,1 and 5 d comparedwith that at 23℃,and 5,4,5 and 7 d compared with that at 28℃,respectively.The LT99 values to eggs,larvae,pupae and adults at 18℃ were 5,1,2 and 7 d longer than that at 23℃,and 6,5,5 and 10 d longer than that at 28℃,respectively.The lethal time of different life stages of the C.ferrugineus strain significantly increased with temperature decreasing.The exposure time of full mortality on pupae at 300 mL/m^3 of phosphine at 18℃ reached 38 d,which was 12 d longer than that of larvae.The order of tolerance of different life stages of C.ferrugineus exposed to 300 mL/m^3 phosphine from high to low was pupae,eggs,adults,larvae at tested temperatures.
基金financially supported by the National Natural Science Foundation of China(Nos.21673077,21473058,and 21273077)
文摘The phosphine-functionalized phosphonium-based ionic liquids(dppm-Q, dppe-Q, dppp-Q and dppb-Q) as the bi-functional ligands enable the efficient one-pot tandem hydroformylationeacetalization. It was found that, in dppm-Q, dppe-Q, dppp-Q and dppb-Q, the incorporated phosphino-fragments were responsible for Rh-catalyzed hydroformylation and the phosphoniums were in charge of the subsequent acetalization as the Lewis acid catalysts. Moreover, the diphosphonium-based ionic liquid of dppb-DQ could be applied as a co-solvent to immobilize the Rh/dppb-Q catalytic system with the advantages of the improved catalytic performance, the available catalyst recyclability, and the wide generality for the substrates.
文摘The new tetracarbonyl - chromium-triphenyl phosphine complex was synthesized and characterized using ultraviolet(UV)-visible,Fourier transform infrared(FTIR),and nuclear magnetic resonance(NMR) techniques.The characterization results confirm the molecular structure of the new complex.The z-scan measurements were done by diode laser[continuous wave(CW)]to estimate the nonlinear optical parameter(X^3).The results led to calculate three parameters:the groundstate cross sections(σ_g),the excited-state cross sections(σ_(ex)),and thermo-optic coefficient of the new complex.This study indicated that our complex is a suitable for photonic applications.