A facile method was introduced and demonstrated to synthesize zinc oxide(ZnO) nanorods(NRs) as an electron transporting layer(ETL) for organic solar cells(OSCs).Hydrothermal synthesis of the NRs showed a constant grow...A facile method was introduced and demonstrated to synthesize zinc oxide(ZnO) nanorods(NRs) as an electron transporting layer(ETL) for organic solar cells(OSCs).Hydrothermal synthesis of the NRs showed a constant growth rate of 5.5 nm min-1 from germination to sub-micrometer length.The properties were characterized using scanning electron microscopy(SEM),transmission electron microscopy(TEM),absorption spectrophotometry and so on.Based on these measurements,the germinant growth mechanism and its corresponding orientation characteristics were investigated.As an ETL of the OSCs,ZnO NRs enhance the charge extraction from the active layer due to their increased interfacial surface area,but there is an optimal length because of the shunt path formation and UV absorption of long ZnO NRs.As a re sult,the OSC with the ZnO NRs as ETL shows power conversion efficiency(PCE) up to 6.2%.The J-V characteristics and incident photon-to-current conversion efficiency(IPCE) measurement also reveal that the efficiency enhancement is an assembly of individual results from optical,physical and electrical characteristic of the ZnO NRs.展开更多
We analytically and numerically compute the Onsager dissociation rate(exciton dissociation)on an interface induced by a piezoelectric potential in an inorganicorganic hybrid p-n junction system(ZnO+(poly(p-phenylene v...We analytically and numerically compute the Onsager dissociation rate(exciton dissociation)on an interface induced by a piezoelectric potential in an inorganicorganic hybrid p-n junction system(ZnO+(poly(p-phenylene vinylene));PPV).When a positive piezoelectric potential is created at the interface region owing to the deformation of the system,free electrons accumulate at the interface.Hence,screening effects are observed.It is assumed that the electron layer formed at the interface then attracts free holes from the p-type PPV region,which leads to exciton formation,possibly via the Langevin recombination process.The increased exciton density can then contribute to the Onsager dissociation rate,which is maximum around the interface.This paper focuses on the role of piezoelectric effects in promoting exciton formation at the interface and its relation with the exciton dissociation rate.展开更多
基金This study was conducted with support from the Korea Institute of Industrial Technology as Research Source Technique Project(KITECH,EO-190008)。
文摘A facile method was introduced and demonstrated to synthesize zinc oxide(ZnO) nanorods(NRs) as an electron transporting layer(ETL) for organic solar cells(OSCs).Hydrothermal synthesis of the NRs showed a constant growth rate of 5.5 nm min-1 from germination to sub-micrometer length.The properties were characterized using scanning electron microscopy(SEM),transmission electron microscopy(TEM),absorption spectrophotometry and so on.Based on these measurements,the germinant growth mechanism and its corresponding orientation characteristics were investigated.As an ETL of the OSCs,ZnO NRs enhance the charge extraction from the active layer due to their increased interfacial surface area,but there is an optimal length because of the shunt path formation and UV absorption of long ZnO NRs.As a re sult,the OSC with the ZnO NRs as ETL shows power conversion efficiency(PCE) up to 6.2%.The J-V characteristics and incident photon-to-current conversion efficiency(IPCE) measurement also reveal that the efficiency enhancement is an assembly of individual results from optical,physical and electrical characteristic of the ZnO NRs.
基金This research was supported by the Office of the Theory&Modeling Based Design of Energy Harvesting,Korea.
文摘We analytically and numerically compute the Onsager dissociation rate(exciton dissociation)on an interface induced by a piezoelectric potential in an inorganicorganic hybrid p-n junction system(ZnO+(poly(p-phenylene vinylene));PPV).When a positive piezoelectric potential is created at the interface region owing to the deformation of the system,free electrons accumulate at the interface.Hence,screening effects are observed.It is assumed that the electron layer formed at the interface then attracts free holes from the p-type PPV region,which leads to exciton formation,possibly via the Langevin recombination process.The increased exciton density can then contribute to the Onsager dissociation rate,which is maximum around the interface.This paper focuses on the role of piezoelectric effects in promoting exciton formation at the interface and its relation with the exciton dissociation rate.