The interfaces between the inorganic metal oxide and organic photoactive layer are of outmost importance for efficiency and stability in organic solar cells(OSCs).Tin oxide(SnO_(2))is one of the promising candidates f...The interfaces between the inorganic metal oxide and organic photoactive layer are of outmost importance for efficiency and stability in organic solar cells(OSCs).Tin oxide(SnO_(2))is one of the promising candidates for the electron transport layer(ETL)in high-performance inverted OSCs.When a solution-processed SnO_(2)ETL is employed,however,the presence of interfacial defects and suboptimal interfacial contact can lower the power conversion efficiency(PCE)and operational stability of OSCs.Herein,highly efficient and stable inverted OSCs by modification of the SnO_(2)surface with ultraviolet(UV)-curable acrylate oligomers(SAR and OCS)are demonstrated.The highest PCEs of 16.6%and 17.0%are achieved in PM6:Y6-BO OSCs with the SAR and OCS,respectively,outperforming a device with a bare SnO_(2)ETL(PCE 13.8%).The remarkable enhancement of PCEs is attributed to the optimized interfacial contact,leading to mitigated surface defects.More strikingly,improved light-soaking and thermal stability strongly correlated with the interfacial defects are demonstrated for OSCs based on SnO_(2)/UV cross-linked resins compared to OSCs utilizing bare SnO_(2).We believe that UV cross-linking oligomers will play a key role as interfacial modifiers in the future fabrication of large-area and flexible OSCs with high efficiency and stability.展开更多
Tandem device architectures offer a route to greatly increase the maximum possible power conversion efficiencies(PCEs)of polymer solar cells,however,the complexity of tandem cell device fabrication(such as selecting b...Tandem device architectures offer a route to greatly increase the maximum possible power conversion efficiencies(PCEs)of polymer solar cells,however,the complexity of tandem cell device fabrication(such as selecting bandgaps of the front and back cells,current matching,thickness,and recombination layer optimization)often result in lower PCEs than are observed in single-junction devices.In this study,we analyze the influence of front cell and back cell bandgaps and use transfer matrix modeling to rationally design and optimize effective tandem solar cell structures before actual device fabrication.Our approach allows us to estimate tandem device parameters based on known absorption coefficients and open-circuit voltages of different active layer materials and design devices without wasting valuable time and materials.Using this approach,we have investigated a series of wide bandgap,high voltage photovoltaic polymers as front cells in tandem devices with PTB7-Th as a back cell.In this way,we have been able to demonstrate tandem devices with PCE of up to 12.8%with minimal consumption of valuable photoactive materials in tandem device optimization.This value represents one of the highest PCE values to date for fullerene-based tandem solar cells.展开更多
Design and synthesis of low bandgap(LBG) polymer donors is inevitably challenging and their processability from a non-halogenated solvent system remains a hurdle to overcome in the area of highperformance polymer sola...Design and synthesis of low bandgap(LBG) polymer donors is inevitably challenging and their processability from a non-halogenated solvent system remains a hurdle to overcome in the area of highperformance polymer solar cells(PSCs).Due to a high aggregation tendency of LBG polymers,especially diketopyrrolopyrrole(DPP)-based polymers coupled with bithiophenes in the polymer backbones,their widespread adoption in non-ha logena ted solvent-processed PSCs has been limited.Herein,a novel LBG DPP-based polymer,called PDPP4 T-1 F with asymmetric arrangement of fluorine atom,has been successfully synthesized and showed an outstanding power conversion efficiency(PCE) of 10.10% in a singlejunction fullerene-based PSCs.Furthermore,an impressive PCE of 13.21% has been achieved in a tandem device from a fully non-halogenated solvent system,which integrates a wide bandgap PDTBTBz-2 F polymer in the bottom cell and LBG PDPP4 T-1 F polymer in the top cell.The achieved efficiency is the highest value reported in the literature to date in fullerene-based tandem PSCs.We found that a uniformly distributed interpenetrating fibril network with nano-scale phase separation and anisotropy of the polymer backbone orientation for efficient charge transfer/transport and suppressed charge recombination in PDPP4 T-1 F-based PSCs led to outstanding PCEs in single and tandem-junction PSCs.展开更多
基金the Partnership for Skills in Applied Sciences,Engineering and Technology(PASET)-Regional Scholarship Innovation Fund(RSIF)(World Bank PASET No.IP22-15)supported by the National Research Foundation(NRF)(NRF-2021R1A2C2091787 and NRF-2022M3H4A1A03076280)+1 种基金the Korea Research Institute of Chemical Technology(KRICT)of the Republic of Korea(No.KS2422-10)the National Research Council of Science and Technology(Grant No.Global-23-007)of Republic of Korea。
文摘The interfaces between the inorganic metal oxide and organic photoactive layer are of outmost importance for efficiency and stability in organic solar cells(OSCs).Tin oxide(SnO_(2))is one of the promising candidates for the electron transport layer(ETL)in high-performance inverted OSCs.When a solution-processed SnO_(2)ETL is employed,however,the presence of interfacial defects and suboptimal interfacial contact can lower the power conversion efficiency(PCE)and operational stability of OSCs.Herein,highly efficient and stable inverted OSCs by modification of the SnO_(2)surface with ultraviolet(UV)-curable acrylate oligomers(SAR and OCS)are demonstrated.The highest PCEs of 16.6%and 17.0%are achieved in PM6:Y6-BO OSCs with the SAR and OCS,respectively,outperforming a device with a bare SnO_(2)ETL(PCE 13.8%).The remarkable enhancement of PCEs is attributed to the optimized interfacial contact,leading to mitigated surface defects.More strikingly,improved light-soaking and thermal stability strongly correlated with the interfacial defects are demonstrated for OSCs based on SnO_(2)/UV cross-linked resins compared to OSCs utilizing bare SnO_(2).We believe that UV cross-linking oligomers will play a key role as interfacial modifiers in the future fabrication of large-area and flexible OSCs with high efficiency and stability.
基金This study was supported by the National Research Foundation of Korea(2017R1C1B1010627)the New and Renewable Energy Program of the Korea Institute of Energy Technology Evaluation and Planning(KETEP)grant funded by the Korea Government Ministry of Trade,Industry and Energy(MTIE)(20163030013900,20183010013900)This study was supported by the Technology Development Program to solve climate changes of the National Research Foundation(NRF)funded by theMinistry of Science,ICT and Future Planning(NRF-2015M1A2A2057506,2019M1A2A2065614).
文摘Tandem device architectures offer a route to greatly increase the maximum possible power conversion efficiencies(PCEs)of polymer solar cells,however,the complexity of tandem cell device fabrication(such as selecting bandgaps of the front and back cells,current matching,thickness,and recombination layer optimization)often result in lower PCEs than are observed in single-junction devices.In this study,we analyze the influence of front cell and back cell bandgaps and use transfer matrix modeling to rationally design and optimize effective tandem solar cell structures before actual device fabrication.Our approach allows us to estimate tandem device parameters based on known absorption coefficients and open-circuit voltages of different active layer materials and design devices without wasting valuable time and materials.Using this approach,we have investigated a series of wide bandgap,high voltage photovoltaic polymers as front cells in tandem devices with PTB7-Th as a back cell.In this way,we have been able to demonstrate tandem devices with PCE of up to 12.8%with minimal consumption of valuable photoactive materials in tandem device optimization.This value represents one of the highest PCE values to date for fullerene-based tandem solar cells.
基金support granted by the National Research Foundation(NRF)(NRF2020M3H4A3081813)by the Korea Institute of Energy Technology Evaluation and Planning(KETEP)(No.20183010013820)by the Korea Research Institute of Chemical Technology(KRICT)(No.KS2022-00)of the Republic of Korea。
文摘Design and synthesis of low bandgap(LBG) polymer donors is inevitably challenging and their processability from a non-halogenated solvent system remains a hurdle to overcome in the area of highperformance polymer solar cells(PSCs).Due to a high aggregation tendency of LBG polymers,especially diketopyrrolopyrrole(DPP)-based polymers coupled with bithiophenes in the polymer backbones,their widespread adoption in non-ha logena ted solvent-processed PSCs has been limited.Herein,a novel LBG DPP-based polymer,called PDPP4 T-1 F with asymmetric arrangement of fluorine atom,has been successfully synthesized and showed an outstanding power conversion efficiency(PCE) of 10.10% in a singlejunction fullerene-based PSCs.Furthermore,an impressive PCE of 13.21% has been achieved in a tandem device from a fully non-halogenated solvent system,which integrates a wide bandgap PDTBTBz-2 F polymer in the bottom cell and LBG PDPP4 T-1 F polymer in the top cell.The achieved efficiency is the highest value reported in the literature to date in fullerene-based tandem PSCs.We found that a uniformly distributed interpenetrating fibril network with nano-scale phase separation and anisotropy of the polymer backbone orientation for efficient charge transfer/transport and suppressed charge recombination in PDPP4 T-1 F-based PSCs led to outstanding PCEs in single and tandem-junction PSCs.
