Owing to the function of manipulating light absorption distribution,tandem organic solar cells containing multiple sub-cells exhibit high power conversion efficiencies.However,there is a substantial challenge in preci...Owing to the function of manipulating light absorption distribution,tandem organic solar cells containing multiple sub-cells exhibit high power conversion efficiencies.However,there is a substantial challenge in precisely controlling the inter-subcells carrier migration which determines the balance of charge transport across the entire device.The conductivity of"nanowires"-like conducting channel in interconnecting layer between sub-cells should be improved which calls for fine engineering on the morphology of polyelectrolyte in interconnecting layer.Here,we develop a simple method to effectively manipulating the domains of conductive components in commercially available polyelectrolyte PEDOT:PSs.The use of poor solvent could effectively modify the configuration of polystyrene sulfonic acid and thus the space for conductive components.Based on our strategy,the insulated shells wrapping conductive domains are thinned and the efficiencies of tandem organic solar cells are improved.We believe our method might provide guidance for the manufacture of tandem organic solar cells.展开更多
Constructing monolithic tandem solar cells (TSCs) is an effective method to break the Shockley–Queisser (S–Q) radiative efficiency limit for single-junction solar cells. Employing the wide bandgap perovskite materia...Constructing monolithic tandem solar cells (TSCs) is an effective method to break the Shockley–Queisser (S–Q) radiative efficiency limit for single-junction solar cells. Employing the wide bandgap perovskite materials and low bandgap organic materials as absorber layers for front and rear subcells, respectively, to construct perovskite/organic TSCs can complementarily absorb sunlight in ultraviolet-visible (UV-Vis) range by front perovskite and near-infrared (NIR) range by rear organic molecules, thus reducing the thermalization energy losses. Besides the subcells, the interconnection layer (ICL), which physically and electrically connects the front and rear subcells, is also an important tunnel junction to recombine charges. In this review, we summarize the optimization strategies of wide bandgap perovskites for front subcell, narrow bandgap organic material for rear subcell, and the ICLs employed in monolithic perovskite/organic TSCs.展开更多
ABSTRACT Organic polymer solar cells （PSCs） have attracted increasing attention due to light weight, low cost, flexibility and roll-to-roll manufacturing. However, the limited light harvest range of the photoactive ...ABSTRACT Organic polymer solar cells （PSCs） have attracted increasing attention due to light weight, low cost, flexibility and roll-to-roll manufacturing. However, the limited light harvest range of the photoactive layer greatly restrains the power conversion efficiency （PCE） enhancement. In order to expand the light absorption range and further enhance the PCE of the PSCs, tandem structures have been designed and demonstrated. In tandem solar cell, the intermediate layer （IML） plays a critical role in physically and electrically connection of the two subcells. Herein, we apply titanium （diisopropoxide） bis（2,4-pentanedionate） （TIPD） as both electrode modification layer and intermediate layer to investigate the feasibility in inverted tandem polymer solar cells. The same photoactive layers of PTB7-Th：PC71BM are adopted in both front and rear subcells to simplify the evaluation of effectiveness of TIPD layer in tandem structures. By modulating the treatment condition of IML and the thickness of photoactive layer, efficient inverted tandem PSCs have been achieved with minimized voltage loss and excellent charge transportation, giving a best Voc of 1.54 V, which is almost two times that of the single bulk heterojunction （BHJ）-PSC （0.78 V） and an enhanced PCE up to 8.11%.展开更多
The concept of tandem solar cells(TSCs) is an effective way to substantially further improve the efficiency of solar cells. The excellent optoelectronic properties and bandgap tunability of perovskites make them promi...The concept of tandem solar cells(TSCs) is an effective way to substantially further improve the efficiency of solar cells. The excellent optoelectronic properties and bandgap tunability of perovskites make them promising for constructing efficient TSCs. Currently, TSCs based on perovskite have been extensively studied. Besides, the performance of organic solar cells has been greatly improved recently due to the wider and more efficient spectral utilization. Accordingly, research on perovskite/organic TSCs has garnered significant attention. It has potential application advantages in emerging fields such as wearable devices by virtue of flexibility. In addition, orthogonal solvents can be adopted to realize the separate preparation of subcells with the solution method, which greatly reduces fabrication complexity;moreover, fabrication with less equipment significantly cuts down the device cost. Meanwhile, organics with more adjustability on the optoelectronic properties provide more tuning strategies for high-performance perovskite/organic TSCs. However, comprehensive and timely reviews on the perovskite/organic TSCs are deficient. Therefore, we expect to accomplish a review on this innovative TSCs to facilitate researchers with a deeper understanding of perovskite/organic TSCs. Herein, we firstly review the significant progress of perovskite and organic solar cells. Then, current achievements of perovskite/organic TSCs are summarized and introduced with a particular focus on the device structure design. Finally, we discuss existential challenges and propose effective strategies for future engineering.展开更多
Organic-inorganic metal-halide perovskite solar cells(PerSCs)have achieved significant progresses due to their outstanding optoelectronic charac-teristics,and the power conversion efficiency(PCE)of single-junction Per...Organic-inorganic metal-halide perovskite solar cells(PerSCs)have achieved significant progresses due to their outstanding optoelectronic charac-teristics,and the power conversion efficiency(PCE)of single-junction PerSCs has been boosted from 3.8%to a certified 25.2%.However,the efficien-cy of single-junction cells is governed by the Shockley-Queisser(S-Q)radiative limit,and fabricating all-perovskite tandem solar cells is a particularly attractive method to break the S-Q limit.Since the bandgap of lead(Pb)-based mixed halide perovskite can be tuned from 1.55 eV to 2.3 eV,and the mixed tin(Sn)-Pb perovskites have bandgap of~1.2 eV,these perovskites become the best candidates for the front and rear subcells of all-perovskite tandem device,respectively.In this review,we firstly summarize the current development progresses of two-terminal(2-T)all-perovskite tandem so-lar cells.For further optimizing the device performance,the wide bandgap mixed halide perovskites for front subcell,mixed Sn-Pb narrow bandgap perovskites for rear subcell,and the interconnection layer(ICL)of 2-T tandem device are then discussed.This review aims to open a pathway to real-ize highly efficient all-perovskite tandem solar cells.展开更多
Organic bulk heterojunction fullerence(C60) doped 5, 6, 11, 12-tetraphenylnaphthacene(rubrene) as the high quality charge generation layer(CGL) with high transparency and superior charge generating capability for tand...Organic bulk heterojunction fullerence(C60) doped 5, 6, 11, 12-tetraphenylnaphthacene(rubrene) as the high quality charge generation layer(CGL) with high transparency and superior charge generating capability for tandem organic light emitting diodes(OLEDs) is developed. This CGL shows excellent optical transparency about 90%, which can reduce the optical interference effect formed in tandem OLEDs. There is a stable white light emission including 468 nm and 500 nm peaks from the blue emitting layer and 620 nm peak from the red emitting layer in tandem white OLEDs. A high efficiency of about 17.4 cd/A and CIE coordinates of(0.40, 0.35) at 100 cd/m2 and(0.36, 0.34) at 1000 cd/m2 have been demonstrated by employing the developed CGL, respectively.展开更多
Perovskite tandem solar cells have recently received extensive attention due to their promise of achieving power conversion efficiency(PCE)beyond the limits of single-junction cells.However,their performance is still ...Perovskite tandem solar cells have recently received extensive attention due to their promise of achieving power conversion efficiency(PCE)beyond the limits of single-junction cells.However,their performance is still largely constrained by the widebandgap perovskite solar cells which show considerable open-circuit voltage(VOC)losses.Here,we increase the VOCand PCE of wide-bandgap perovskite solar cells by changing the hole transport layer(HTL)from commonly used poly(bis(4-phenyl)(2,4,6-trimethylphenyl)amine)(PTAA)to in-situ cross-linked small molecule N_(4),N_(4)′-di(naphthalen-1-yl)-N_(4),N_(4)′-bis(4-vinylphenyl)biphenyl-4,4′-diamine(VNPB).The stronger interaction and lower trap density at the VNPB/perovskite interface improve the PCE and stability of wide-bandgap perovskite solar cells.By using the cross-linked HTL for front wide-bandgap subcells,PCEs of 24.9%and 25.4%have been achieved in perovskite/perovskite and perovskite/silicon tandem solar cells,respectively.The results demonstrate that cross-linkable small molecules are promising for high-efficiency and cost-effective perovskite tandem photovoltaic devices.展开更多
Tandem cell with structure of indium tin oxide(ITO)/molybdenum oxide(MoO_(3))/fullerene(C60)/copper phthalocyanine(CuPc)/C60/tris-8-hydroxy-quinolinato aluminum(Alq_(3))/Al was fabricated to study the effect of net ca...Tandem cell with structure of indium tin oxide(ITO)/molybdenum oxide(MoO_(3))/fullerene(C60)/copper phthalocyanine(CuPc)/C60/tris-8-hydroxy-quinolinato aluminum(Alq_(3))/Al was fabricated to study the effect of net carriers at the interconnection layer. The open circuit voltage and short circuit current were found to be 1.15 V and 0.56 mA/cm^(2),respectively. Almost the same performance(1.05 V, 0.58 mA/cm^(2)) of tandem cell with additional recombination layer(ITO/MoO_(3)/C60/Alq_(3)/Al/Ag/MoO_(3)/CuPc/C60/Alq_(3)/Al) demonstrates that the carrier balance is more crucial than carrier recombination. The net holes at the interconnection layer caused by more carrier generation from the back cell on one hand would enhance the recombination with electrons from the front cell and on the other hand would quench the excitons produced in CuPc of the back cell.展开更多
This paper has reviewed:(1) the two unique advantages of tandem organic solar cells(OSCs) compared to single OSCs;(2) the challengings as well as strategies to develop qualified interconnecting layer(ICL) for tandem O...This paper has reviewed:(1) the two unique advantages of tandem organic solar cells(OSCs) compared to single OSCs;(2) the challengings as well as strategies to develop qualified interconnecting layer(ICL) for tandem OSCs.More specifically,firstly,the two key advantages unique to tandem OSCs as compared to single OSCs,namely minimizing sub-bandgap transmission and thermalization loss as well as realizing optical thick and electrical thin structures,have been discussed.Secondly,the ICL,as one of the most challenging issue in tandem OSCs that needs to fulfill the optical,electrical and mechanical requirements simultaneously to realize a qualified ICL has been reviewed.As one of the most challenging requirement among the three,the electrical requirement and its corresponding three different solving strategies have been discussed in detail,revealing a bright future for developing a general strategy to realizing qualified ICL composed of different hole transporting layer(HTL) and electron transporting layer(ETL).展开更多
The photovoltaic performance of perovskite solar cells(PSCs)can be improved by utilizing efficient front contact.However,it has always been a significant challenge for fabricating high-quality,scalable,controllable,an...The photovoltaic performance of perovskite solar cells(PSCs)can be improved by utilizing efficient front contact.However,it has always been a significant challenge for fabricating high-quality,scalable,controllable,and cost-effective front contact.This study proposes a realistic multi-layer front contact design to realize efficient single-junction PSCs and perovskite/perovskite tandem solar cells(TSCs).As a critical part of the front contact,we prepared a highly compact titanium oxide(TiO2)film by industrially viable Spray Pyrolysis Deposition(SPD),which acts as a potential electron transport layer(ETL)for the fabrication of PSCs.Optimization and reproducibility of the TiO2 ETL were discreetly investigated while fabricating a set of planar PSCs.As the front contact has a significant influence on the optoelectronic properties of PSCs,hence,we investigated the optics and electrical effects of PSCs by three-dimensional(3D)finite-difference time-domain(FDTD)and finite element method(FEM)rigorous simulations.The investigation allows us to compare experimental results with the outcome from simulations.Furthermore,an optimized single-junction PSC is designed to enhance the energy conversion efficiency(ECE)by>30% compared to the planar reference PSC.Finally,the study has been progressed to the realization of all-perovskite TSC that can reach the ECE,exceeding 30%.Detailed guidance for the completion of high-performance PSCs is provided.展开更多
In the present paper,computational fluid dynamics(CFD) simulations were executed to exploring the intent of using aspirated cascade to replace tandem cascades.Firstly,the ONERA tandem cascades were investigated,and th...In the present paper,computational fluid dynamics(CFD) simulations were executed to exploring the intent of using aspirated cascade to replace tandem cascades.Firstly,the ONERA tandem cascades were investigated,and the performance of the cascades at the design point were listed,such as diffusion factor,total pressure loss coefficient,deviation angle etc.For replacing the ONERA tandem cascades,a new cascade was designed with the codes BLADEGEN developed by the authors.The quasi 3-D calculations were carried out using the collection of programs for cascade analysis and design,MISES.The cascade was analyzed and designed by using this code.And the cascade was simulated and analyzed by commercial CFD software.It is found there is an obvious separation on the suction side.Based on the 3D CFD simulation results of the cascade without aspiration,an aspirated cascade was designed by introducing a slot on the suction side.The performance of the aspirated cascade was investigated and compared with the tandem cascades,indicated that under the same inlet condition,the total pressure loss of the single row aspirated cascade was less than that of the tandem cascades,and the outlet static pressure is higher than that of the tandem cascades.Meanwhile,the different suction slot location,suction width and suction mass flow are studied for the aspirated cascade.展开更多
In this paper, a significant enhancement in current efficiency of the green tandem organic light-emitting diodes(TOLEDs) is demonstrated, which is based on a buffer-modified charge generation layer(CGL) of fullerene c...In this paper, a significant enhancement in current efficiency of the green tandem organic light-emitting diodes(TOLEDs) is demonstrated, which is based on a buffer-modified charge generation layer(CGL) of fullerene carbon(C60)/zinc-phthalocyanine(ZnPc). Al and MoO3 were used as the buffer-modified layers on both sides of the bilayer C60/ZnPc, respectively. Experimental results show that the inserted Al and MoO3 layers can effectively increase the electron extraction of the CGL for obtaining the device performance enhancement. Compared with that of the green TOLEDs without buffer-modified layers in CGL(37.3 cd·A-1), the current efficiency of the green TOLEDs is increased to 54.1 cd·A-1. Further study results find that the performance can also be improved by optimizing the thickness of Al in the CGL. The maximum current efficiency and maximum luminance of the green TOLEDs achieve 63.5 cd·A-1 and 17 873 cd·m-2, respectively, when the multilayer structure of the CGL is Al(3 nm)/C60(5 nm)/ZnPc(5 nm)/MoO3(3 nm).展开更多
Compared to conventional quantum dot light-emitting diodes,tandem quantum dot light-emitting diodes(TQLEDs)possess higher device efficiency and more applications in the field of flat panel display and solid-state ligh...Compared to conventional quantum dot light-emitting diodes,tandem quantum dot light-emitting diodes(TQLEDs)possess higher device efficiency and more applications in the field of flat panel display and solid-state lighting in the future.The TQLED is a multilayer structure device which connects two or more light-emitting units by using an interconnection layer(ICL),which plays an extremely important role in the TQLED.Therefore,realizing an effective ICL is the key to obtain high-efficiency TQLEDs.In this work,the p-type materials polys(3,4-ethylenedioxythiophene),poly(styrenesulfonate)(PEDOT:PSS)and the n-type material zinc magnesium oxide(ZnMgO),were used,and an effective hybrid ICL,the PEDOT:PSS-GO/ZnMgO,was obtained by doping graphene oxide(GO)into PEDOT:PSS.The effect of GO additive on the ICL was systematically investigated.It exhibits that the GO additive brought the fine charge carrier generation and injection capacity simultaneously.Thus,the all solutionprocessed red TQLEDs were prepared and characterized for the first time.The maximum luminance of 40877 cd/m^(2) and the highest current efficiency of 19.6 cd/A were achieved,respectively,showing a 21%growth and a 51%increase when compared with those of the reference device without GO.The encouraging results suggest that our investigation paves the way for efficient all solution-processed TQLEDs.展开更多
基金the National Natural Science Foundation of China(NSFC)(22275016,21835006,22122905)Beijing Municipal Science&Technology Commission(2232078)+2 种基金Beijing National Laboratory for Molecular Sciences(BNLMS)Junior Fellow(2019BMS20014,BNLMS-CXXM-201903)National Research Council of Science and Technology of Korea(Global20-004)the Key Research Program of the Chinese Academy of Sciences(XDPB13-3).
文摘Owing to the function of manipulating light absorption distribution,tandem organic solar cells containing multiple sub-cells exhibit high power conversion efficiencies.However,there is a substantial challenge in precisely controlling the inter-subcells carrier migration which determines the balance of charge transport across the entire device.The conductivity of"nanowires"-like conducting channel in interconnecting layer between sub-cells should be improved which calls for fine engineering on the morphology of polyelectrolyte in interconnecting layer.Here,we develop a simple method to effectively manipulating the domains of conductive components in commercially available polyelectrolyte PEDOT:PSs.The use of poor solvent could effectively modify the configuration of polystyrene sulfonic acid and thus the space for conductive components.Based on our strategy,the insulated shells wrapping conductive domains are thinned and the efficiencies of tandem organic solar cells are improved.We believe our method might provide guidance for the manufacture of tandem organic solar cells.
基金supported by the National Natural Science Foundation of China(Nos.51873007,21835006,51961165102 and52003022).
文摘Constructing monolithic tandem solar cells (TSCs) is an effective method to break the Shockley–Queisser (S–Q) radiative efficiency limit for single-junction solar cells. Employing the wide bandgap perovskite materials and low bandgap organic materials as absorber layers for front and rear subcells, respectively, to construct perovskite/organic TSCs can complementarily absorb sunlight in ultraviolet-visible (UV-Vis) range by front perovskite and near-infrared (NIR) range by rear organic molecules, thus reducing the thermalization energy losses. Besides the subcells, the interconnection layer (ICL), which physically and electrically connects the front and rear subcells, is also an important tunnel junction to recombine charges. In this review, we summarize the optimization strategies of wide bandgap perovskites for front subcell, narrow bandgap organic material for rear subcell, and the ICLs employed in monolithic perovskite/organic TSCs.
文摘ABSTRACT Organic polymer solar cells （PSCs） have attracted increasing attention due to light weight, low cost, flexibility and roll-to-roll manufacturing. However, the limited light harvest range of the photoactive layer greatly restrains the power conversion efficiency （PCE） enhancement. In order to expand the light absorption range and further enhance the PCE of the PSCs, tandem structures have been designed and demonstrated. In tandem solar cell, the intermediate layer （IML） plays a critical role in physically and electrically connection of the two subcells. Herein, we apply titanium （diisopropoxide） bis（2,4-pentanedionate） （TIPD） as both electrode modification layer and intermediate layer to investigate the feasibility in inverted tandem polymer solar cells. The same photoactive layers of PTB7-Th：PC71BM are adopted in both front and rear subcells to simplify the evaluation of effectiveness of TIPD layer in tandem structures. By modulating the treatment condition of IML and the thickness of photoactive layer, efficient inverted tandem PSCs have been achieved with minimized voltage loss and excellent charge transportation, giving a best Voc of 1.54 V, which is almost two times that of the single bulk heterojunction （BHJ）-PSC （0.78 V） and an enhanced PCE up to 8.11%.
基金financial support from the National Key Research and Development Program of China,China (Grant No.2022YFB4200203)the Key project of Nature Science Foundation of Tianjin,China (22JCZDJC00120)the 111 Project,China(B16027)。
文摘The concept of tandem solar cells(TSCs) is an effective way to substantially further improve the efficiency of solar cells. The excellent optoelectronic properties and bandgap tunability of perovskites make them promising for constructing efficient TSCs. Currently, TSCs based on perovskite have been extensively studied. Besides, the performance of organic solar cells has been greatly improved recently due to the wider and more efficient spectral utilization. Accordingly, research on perovskite/organic TSCs has garnered significant attention. It has potential application advantages in emerging fields such as wearable devices by virtue of flexibility. In addition, orthogonal solvents can be adopted to realize the separate preparation of subcells with the solution method, which greatly reduces fabrication complexity;moreover, fabrication with less equipment significantly cuts down the device cost. Meanwhile, organics with more adjustability on the optoelectronic properties provide more tuning strategies for high-performance perovskite/organic TSCs. However, comprehensive and timely reviews on the perovskite/organic TSCs are deficient. Therefore, we expect to accomplish a review on this innovative TSCs to facilitate researchers with a deeper understanding of perovskite/organic TSCs. Herein, we firstly review the significant progress of perovskite and organic solar cells. Then, current achievements of perovskite/organic TSCs are summarized and introduced with a particular focus on the device structure design. Finally, we discuss existential challenges and propose effective strategies for future engineering.
基金supported by the National Natural Science Foundation of China(Nos.51873007,21835006,51961165102,51772218)the Open Project of Key Laboratory of Solar Energy Utilization&Energy Saving Technology of Zhejiang Province(ZJS-OP-2020-04)the State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources(Grant No.LAPS20003).
文摘Organic-inorganic metal-halide perovskite solar cells(PerSCs)have achieved significant progresses due to their outstanding optoelectronic charac-teristics,and the power conversion efficiency(PCE)of single-junction PerSCs has been boosted from 3.8%to a certified 25.2%.However,the efficien-cy of single-junction cells is governed by the Shockley-Queisser(S-Q)radiative limit,and fabricating all-perovskite tandem solar cells is a particularly attractive method to break the S-Q limit.Since the bandgap of lead(Pb)-based mixed halide perovskite can be tuned from 1.55 eV to 2.3 eV,and the mixed tin(Sn)-Pb perovskites have bandgap of~1.2 eV,these perovskites become the best candidates for the front and rear subcells of all-perovskite tandem device,respectively.In this review,we firstly summarize the current development progresses of two-terminal(2-T)all-perovskite tandem so-lar cells.For further optimizing the device performance,the wide bandgap mixed halide perovskites for front subcell,mixed Sn-Pb narrow bandgap perovskites for rear subcell,and the interconnection layer(ICL)of 2-T tandem device are then discussed.This review aims to open a pathway to real-ize highly efficient all-perovskite tandem solar cells.
基金Project supported by the National Natural Science Foundation of China （Grant No. 60906022）, the Natural Science Foundation of Tianjin, China （Grant No. 10JCYBJC01100）, the Scientific Developing Foundation of Tianjin Education Commission, China （Grant No. 2011ZD02）, and the Tianjin Natural Science
文摘Organic bulk heterojunction fullerence(C60) doped 5, 6, 11, 12-tetraphenylnaphthacene(rubrene) as the high quality charge generation layer(CGL) with high transparency and superior charge generating capability for tandem organic light emitting diodes(OLEDs) is developed. This CGL shows excellent optical transparency about 90%, which can reduce the optical interference effect formed in tandem OLEDs. There is a stable white light emission including 468 nm and 500 nm peaks from the blue emitting layer and 620 nm peak from the red emitting layer in tandem white OLEDs. A high efficiency of about 17.4 cd/A and CIE coordinates of(0.40, 0.35) at 100 cd/m2 and(0.36, 0.34) at 1000 cd/m2 have been demonstrated by employing the developed CGL, respectively.
基金financially supported by the National Key R&D Program of China(2018YFB1500102)the National Natural Science Foundation of China(61974063,22005139)+5 种基金Natural Science Foundation of Jiangsu Province(BK20202008,BK20190315)Fundamental Research Funds for the Central Universities(0205/14380252)Program for Innovative Talents and Entrepreneur in Jiangsusupported by the National Natural Science Foundation of China(62074153)Strategic Priority Research Program of Chinese Academy of Sciences(XDA17020403)Science and Technology Commission of Shanghai(19DZ1207602 and 20DZ1207103)。
文摘Perovskite tandem solar cells have recently received extensive attention due to their promise of achieving power conversion efficiency(PCE)beyond the limits of single-junction cells.However,their performance is still largely constrained by the widebandgap perovskite solar cells which show considerable open-circuit voltage(VOC)losses.Here,we increase the VOCand PCE of wide-bandgap perovskite solar cells by changing the hole transport layer(HTL)from commonly used poly(bis(4-phenyl)(2,4,6-trimethylphenyl)amine)(PTAA)to in-situ cross-linked small molecule N_(4),N_(4)′-di(naphthalen-1-yl)-N_(4),N_(4)′-bis(4-vinylphenyl)biphenyl-4,4′-diamine(VNPB).The stronger interaction and lower trap density at the VNPB/perovskite interface improve the PCE and stability of wide-bandgap perovskite solar cells.By using the cross-linked HTL for front wide-bandgap subcells,PCEs of 24.9%and 25.4%have been achieved in perovskite/perovskite and perovskite/silicon tandem solar cells,respectively.The results demonstrate that cross-linkable small molecules are promising for high-efficiency and cost-effective perovskite tandem photovoltaic devices.
基金supported by the National Natural Science Foundation of China (Grant Nos. 11774293, 1207432, and 61874016)。
文摘Tandem cell with structure of indium tin oxide(ITO)/molybdenum oxide(MoO_(3))/fullerene(C60)/copper phthalocyanine(CuPc)/C60/tris-8-hydroxy-quinolinato aluminum(Alq_(3))/Al was fabricated to study the effect of net carriers at the interconnection layer. The open circuit voltage and short circuit current were found to be 1.15 V and 0.56 mA/cm^(2),respectively. Almost the same performance(1.05 V, 0.58 mA/cm^(2)) of tandem cell with additional recombination layer(ITO/MoO_(3)/C60/Alq_(3)/Al/Ag/MoO_(3)/CuPc/C60/Alq_(3)/Al) demonstrates that the carrier balance is more crucial than carrier recombination. The net holes at the interconnection layer caused by more carrier generation from the back cell on one hand would enhance the recombination with electrons from the front cell and on the other hand would quench the excitons produced in CuPc of the back cell.
基金supported by the General Research Fund(HKU711813)the Collaborative Research Fund(C7045-14E)from the Research Grants Council of Hong Kong Special Administrative Region,China,the Environment and Conservation Found Project(33/2015)from Environment and Conservation Fundthe CAS-Croucher Funding Scheme for Joint Laboratories(CAS14601)
文摘This paper has reviewed:(1) the two unique advantages of tandem organic solar cells(OSCs) compared to single OSCs;(2) the challengings as well as strategies to develop qualified interconnecting layer(ICL) for tandem OSCs.More specifically,firstly,the two key advantages unique to tandem OSCs as compared to single OSCs,namely minimizing sub-bandgap transmission and thermalization loss as well as realizing optical thick and electrical thin structures,have been discussed.Secondly,the ICL,as one of the most challenging issue in tandem OSCs that needs to fulfill the optical,electrical and mechanical requirements simultaneously to realize a qualified ICL has been reviewed.As one of the most challenging requirement among the three,the electrical requirement and its corresponding three different solving strategies have been discussed in detail,revealing a bright future for developing a general strategy to realizing qualified ICL composed of different hole transporting layer(HTL) and electron transporting layer(ETL).
基金supported in part by the Research and Study Project of Tokai University General Research Organization and by the Grant-in-Aid for Scientific Research Grant Number 20H02838the Universiti Kebangsaan Malaysia for supporting this study through FRGS/1/2017/TK07/UKM/02/9 Grantsupported by the Research Grants Council of Hong Kong,China(Project Number:152093/18E).
文摘The photovoltaic performance of perovskite solar cells(PSCs)can be improved by utilizing efficient front contact.However,it has always been a significant challenge for fabricating high-quality,scalable,controllable,and cost-effective front contact.This study proposes a realistic multi-layer front contact design to realize efficient single-junction PSCs and perovskite/perovskite tandem solar cells(TSCs).As a critical part of the front contact,we prepared a highly compact titanium oxide(TiO2)film by industrially viable Spray Pyrolysis Deposition(SPD),which acts as a potential electron transport layer(ETL)for the fabrication of PSCs.Optimization and reproducibility of the TiO2 ETL were discreetly investigated while fabricating a set of planar PSCs.As the front contact has a significant influence on the optoelectronic properties of PSCs,hence,we investigated the optics and electrical effects of PSCs by three-dimensional(3D)finite-difference time-domain(FDTD)and finite element method(FEM)rigorous simulations.The investigation allows us to compare experimental results with the outcome from simulations.Furthermore,an optimized single-junction PSC is designed to enhance the energy conversion efficiency(ECE)by>30% compared to the planar reference PSC.Finally,the study has been progressed to the realization of all-perovskite TSC that can reach the ECE,exceeding 30%.Detailed guidance for the completion of high-performance PSCs is provided.
基金funded by the International S&T Cooperation Program (No.2010DFB70620) of china
文摘In the present paper,computational fluid dynamics(CFD) simulations were executed to exploring the intent of using aspirated cascade to replace tandem cascades.Firstly,the ONERA tandem cascades were investigated,and the performance of the cascades at the design point were listed,such as diffusion factor,total pressure loss coefficient,deviation angle etc.For replacing the ONERA tandem cascades,a new cascade was designed with the codes BLADEGEN developed by the authors.The quasi 3-D calculations were carried out using the collection of programs for cascade analysis and design,MISES.The cascade was analyzed and designed by using this code.And the cascade was simulated and analyzed by commercial CFD software.It is found there is an obvious separation on the suction side.Based on the 3D CFD simulation results of the cascade without aspiration,an aspirated cascade was designed by introducing a slot on the suction side.The performance of the aspirated cascade was investigated and compared with the tandem cascades,indicated that under the same inlet condition,the total pressure loss of the single row aspirated cascade was less than that of the tandem cascades,and the outlet static pressure is higher than that of the tandem cascades.Meanwhile,the different suction slot location,suction width and suction mass flow are studied for the aspirated cascade.
基金supported by the Scientific and Technological Research Foundation of Chongqing Municipal Education Commission(No.KJ1600439)the Basic and Advanced Technology Research Project of Chongqing Municipality(No.cstc2018jcyjAX0462)the Scientific and Technological Research Foundation of Chongqing Municipal Education Commission(No.KJ1500404)
文摘In this paper, a significant enhancement in current efficiency of the green tandem organic light-emitting diodes(TOLEDs) is demonstrated, which is based on a buffer-modified charge generation layer(CGL) of fullerene carbon(C60)/zinc-phthalocyanine(ZnPc). Al and MoO3 were used as the buffer-modified layers on both sides of the bilayer C60/ZnPc, respectively. Experimental results show that the inserted Al and MoO3 layers can effectively increase the electron extraction of the CGL for obtaining the device performance enhancement. Compared with that of the green TOLEDs without buffer-modified layers in CGL(37.3 cd·A-1), the current efficiency of the green TOLEDs is increased to 54.1 cd·A-1. Further study results find that the performance can also be improved by optimizing the thickness of Al in the CGL. The maximum current efficiency and maximum luminance of the green TOLEDs achieve 63.5 cd·A-1 and 17 873 cd·m-2, respectively, when the multilayer structure of the CGL is Al(3 nm)/C60(5 nm)/ZnPc(5 nm)/MoO3(3 nm).
基金Project(11904298)supported by the National Natural Science Foundation of ChinaProject(cstc2020jcyj-msxm X0586)supported by Chongqing Natural Science Foundation,ChinaProject(S202010635001)supported by Chongqing Municipal Training Program of Innovation and Entrepreneurship for Undergraduates,China。
文摘Compared to conventional quantum dot light-emitting diodes,tandem quantum dot light-emitting diodes(TQLEDs)possess higher device efficiency and more applications in the field of flat panel display and solid-state lighting in the future.The TQLED is a multilayer structure device which connects two or more light-emitting units by using an interconnection layer(ICL),which plays an extremely important role in the TQLED.Therefore,realizing an effective ICL is the key to obtain high-efficiency TQLEDs.In this work,the p-type materials polys(3,4-ethylenedioxythiophene),poly(styrenesulfonate)(PEDOT:PSS)and the n-type material zinc magnesium oxide(ZnMgO),were used,and an effective hybrid ICL,the PEDOT:PSS-GO/ZnMgO,was obtained by doping graphene oxide(GO)into PEDOT:PSS.The effect of GO additive on the ICL was systematically investigated.It exhibits that the GO additive brought the fine charge carrier generation and injection capacity simultaneously.Thus,the all solutionprocessed red TQLEDs were prepared and characterized for the first time.The maximum luminance of 40877 cd/m^(2) and the highest current efficiency of 19.6 cd/A were achieved,respectively,showing a 21%growth and a 51%increase when compared with those of the reference device without GO.The encouraging results suggest that our investigation paves the way for efficient all solution-processed TQLEDs.
