钙钛矿太阳能电池(perovskite solar cells,PVSCs)因长期稳定性差和制造成本高难以实现工业化生产。其制备中最常用的空穴传输材料(hole-transporting materials,HTMs)为2,2′,7,7′-四[N,N-二(4-甲氧基苯基)氨基]-9,9′-螺二芴,需一定...钙钛矿太阳能电池(perovskite solar cells,PVSCs)因长期稳定性差和制造成本高难以实现工业化生产。其制备中最常用的空穴传输材料(hole-transporting materials,HTMs)为2,2′,7,7′-四[N,N-二(4-甲氧基苯基)氨基]-9,9′-螺二芴,需一定量吸湿添加剂以实现高效的空穴提取,导致对水敏感的钙钛矿层受到破坏。无掺杂HTMs避免了吸湿添加剂的使用,且成本低、合成步骤简单。综述了应用于n-i-p型PVSCs的YT5、M7-TFSI、P3HT、PBDB-Cz等高效率无掺杂有机小分子以及聚合物HTMs,提出了理想HTMs在器件性能、分子结构、合成条件、经济成本等方面的设计原则,并展望了无掺杂HTMs在PVSCs商业化过程中的应用前景。展开更多
Three types of blue-violet light-emitting devices based on an excito n- confined structure have been prepared, in which different materials were used as emitting layers and hole-transporting layers. They had structur...Three types of blue-violet light-emitting devices based on an excito n- confined structure have been prepared, in which different materials were used as emitting layers and hole-transporting layers. They had structures of ITO/CuPc/ NPB/CPB/TPBi/Alq 3/LiF/Al(D NC), ITO/CuPc/J03/CBP/TPBi/Alq 3/LiF/Al(D JC) and ITO /CuPc/J03/FNPD/TPBi/Alq 3/LiF/Al(D JF). Here copper phthaloc yan ine (CuPc) acted as hole-injecting layer(HIL), N,N-bis-(1-naphthyl)-N,N-di phenyl-1.1bipheny1-4-4-diamine(NPB) and J03 hole-transporting layers (HTLs) , 4,4'-dicarbazolyl-1,1'-biphenyl (CBP) and FNPD as emitting layers(EMLs), N, arylbenzimidazoles (TPBi) as hole-blocking layer(HBL), and tris(8-quinolinolat o) aluminium complex(Alq 3) as electron-transporting layer(ETL). TPBi applied her e is a good confinement to both charges and excitons, which make the devices emit blue-violet light or iginating from the emitter, CBP and FNPD. Their characteristics have also been i nvestigated. The result shows that the device D NC based on NPB/CBP has the best performance among the three devices. The excellence of D NC is attrib uted to the better hole-transporting ability of NPB as compared with J03, and t he better emitting ability of CBP as compared with FNPD, although the best match ing of energy levels is found in the hole-transporting layer and emitting layer of the device D JF.展开更多
There have been huge achievements of all-perovskite tandem solar cells,which recently realized the highest power conversion efficiency of 24.8%.However,the complex device structure and complicated manufacture processe...There have been huge achievements of all-perovskite tandem solar cells,which recently realized the highest power conversion efficiency of 24.8%.However,the complex device structure and complicated manufacture processes severely restrict the further development of all-perovskite tandem solar cells.In this work,we successfully fabricated high-efficiency hole transport material-free(HTM-free)Sn−Pb alloyed narrow bandgap perovskite solar cells(PSCs)by introducing guanidinium thiocyanate(GASCN)and hydroiodic acid(HI)into the perovskite precursor solution.GASCN and HI play a positive synergy effect during perovskite crystallization process resulting in larger grain size,fewer surface defects,and lower trap density to suppress the Sn^(2+)oxidation degradation.Furthermore,they could effectively adjust the energy level of perovskite materials,reduce the energy level difference between perovskite and ITO resulting in more efficiently transport of free hole charge carriers.As a result,with adding GASCN and HI,the achieved highest power conversion efficiency of HTM-free devices increased from 12.58%to 17.85%,which is one of the highest PCEs among all values reported to date for the HTM-free narrow-bandgap(1.2-1.4 eV)Sn−Pb binary PSCs.Moreover,the optimized device shows improved environmental stability.Our additive strategy manifests a remarkable step towards the facile,cost-efficient fabrication of HTM-free perovskite-based tandem solar cells with both high efficiency and simple fabrication process.展开更多
The development of p-i-n structured perovskite solar cells(PSCs) requires more extensive explorations on seeking efficient, low cost and stable hole transporting materials(HTMs). Small molecular HTMs are superior to p...The development of p-i-n structured perovskite solar cells(PSCs) requires more extensive explorations on seeking efficient, low cost and stable hole transporting materials(HTMs). Small molecular HTMs are superior to polymeric ones in terms of synthetic reproducibility as well as purity. However, thin films composed of small molecules are usually labile during the solution-based perovskite deposition. Herein, we propose a molecular engineering strategy of incorporating oligothiophene as conjugation bridge to develop robust oligomer HTMs for p-i-n type PSCs. Upon increasing the oligothiophene chain length from α-bithiophene to α-quaterthiophene and α-hexathiophene, their HOMO energy levels remain unchanged, but their solubility in common organic solvents decreased remarkably, thus greatly enhancing their tolerance to the perovskite deposition. The rational design of oligothiophene chain length can effectively tune their optoelectronic properties as well as thin film stability under polar solvent soaking. The best performance is achieved by an α-quaterthiophene based HTM(QT), showing a high efficiency of 17.69% with fill factor of 0.81, which are comparable to those of a commercially available benchmark polymer HTM(poly[bis(4-phenyl)(2,4-dimethylphenyl) amine], PTAA) based devices fabricated under the same conditions. Our developed oligomer system not only provides the definite molecular structures like small molecule-type HTMs, but also exhibits the excellent filmforming like polymer-type HTMs, thus achieving the well-balanced parameters among solvent tolerance, thin film conductivity,and interfacial charge transfer efficiency, especially building up a platform to develop low cost and reproducible efficient HTMs in p-i-n structured perovskite solar cells.展开更多
Nickel oxide(NiOx)has exhibited great potential as an inorganic hole transport layer(HTL)in perovskite solar cells(PSCs)due to its wide optical bandgap and superior stability.In this study,we have modulated the Ni26 v...Nickel oxide(NiOx)has exhibited great potential as an inorganic hole transport layer(HTL)in perovskite solar cells(PSCs)due to its wide optical bandgap and superior stability.In this study,we have modulated the Ni26 vacancies in NiOx film by controlling deposition temperature in a hot-casting process,resulting the change of coordination structure and charge state of NiOx.Moreover,the change of the HOMO level of NiOx makes it more compatible with perovskite to decrease energy losses and enhance hole carrier injection efficiency.Besides,the defect modulation in the electronic structure of NiOx is beneficial for increasing the electrical conductivity and mobility,which are considered to achieve the balance of charge carrier transport and avoid charge accumulation at the interface between perovskite and HTL effectively.Both experimental analyses and theoretical calculations reveal the increase of nickel vacancy defects change the electronic structure of NiOx by increasing the ratio of Ni3^+/Ni2^+-and improving the p-type characteristics.Accordingly,an optimal deposition temperature at 120℃enabled a 36.24%improvement in the power conversion efficiency compared to that deposited at room temperature(25℃).Therefore,this work provides a facile method to manipulate the electronic structure of NiOx to improve the charge carrier transport and photovoltaic performance of related PSCs.展开更多
Continuous success has been achieved for solution-processed inorganic-organic hybrid perovskite solar cells（PVSCs） in the past several years, in which organic charge transporting materials play an important role. At...Continuous success has been achieved for solution-processed inorganic-organic hybrid perovskite solar cells（PVSCs） in the past several years, in which organic charge transporting materials play an important role. At present, most of the commonly used hole-transporting materials（HTMs） such as spiro-OMeTAD derivatives for PVSCs require additional chemical doping process to ensure sufficient conductivity and shift the Fermi level towards the HOMO level for efficient hole transport and collection. However, this doping process not only increases the complexity and cost of device fabrication, but also decreases the device stability. Thus development of efficient dopant-free HTMs for PVSCs is highly desirable and remains as a major challenge in this field. In this review, we will summarize the recent advances in the molecular design of dopant-free HTMs for PVSCs.展开更多
Organic π-functional molecules are the foundation and basic component of organic optoelectronic devices.For example,for ideal carrier transporting materials,extended π-conjugation and ordered π-πstacking are neces...Organic π-functional molecules are the foundation and basic component of organic optoelectronic devices.For example,for ideal carrier transporting materials,extended π-conjugation and ordered π-πstacking are necessary to enhance the charge mobility and achieve desirable results.As a promising way to convert sunlight into electricity,organometal halide perovskite solar cells（PSCs） have captured a lot of attention due to its predominant merits especially in the aspect of remarkable photovoltaic performance and much potentially low production cost.For conventional planar PSC structure,hole-transporting layer which typically consists of organic π-functional materials plays a key role in suppressing holeelectron pair recombination,promoting charge transporting and ensuring ohmic contact of back electrode.Considering the key roles of HTMs and its soaring progress in recent years,here,we will summarize recent progress in small organic π-functional materials from its diverse functions in PSCs.Besides,aiming to further promote the development of organic π-functional molecules and HTMs,a promising direction toward highly efficient HTMs will also be discussed.展开更多
N,N-Di-p-tolylaminophenyl)ethenyl]phenyl}-5-(4-bromophenyl)- 1,3,4-oxadiazole (1) containing triarylamine and 2,5-diaryl-1,3,4-oxadiazole units was prepared by Horner-Witting reactions. The structure of the compoun...N,N-Di-p-tolylaminophenyl)ethenyl]phenyl}-5-(4-bromophenyl)- 1,3,4-oxadiazole (1) containing triarylamine and 2,5-diaryl-1,3,4-oxadiazole units was prepared by Horner-Witting reactions. The structure of the compound was confirmed by 1H NMR, IR, MS and elemental analyses. The crystal structure of 1 was determined by X-ray diffraction analysis. UV absorption spectra and photoluminescent spectra were measured.展开更多
文摘钙钛矿太阳能电池(perovskite solar cells,PVSCs)因长期稳定性差和制造成本高难以实现工业化生产。其制备中最常用的空穴传输材料(hole-transporting materials,HTMs)为2,2′,7,7′-四[N,N-二(4-甲氧基苯基)氨基]-9,9′-螺二芴,需一定量吸湿添加剂以实现高效的空穴提取,导致对水敏感的钙钛矿层受到破坏。无掺杂HTMs避免了吸湿添加剂的使用,且成本低、合成步骤简单。综述了应用于n-i-p型PVSCs的YT5、M7-TFSI、P3HT、PBDB-Cz等高效率无掺杂有机小分子以及聚合物HTMs,提出了理想HTMs在器件性能、分子结构、合成条件、经济成本等方面的设计原则,并展望了无掺杂HTMs在PVSCs商业化过程中的应用前景。
基金Project supported by the National Natural Science Foundation of China ( Grant Nos. 60077020 90201034) and the Foundation of National High Technology Research and Development Program (Grant No.2001AA313070)
文摘Three types of blue-violet light-emitting devices based on an excito n- confined structure have been prepared, in which different materials were used as emitting layers and hole-transporting layers. They had structures of ITO/CuPc/ NPB/CPB/TPBi/Alq 3/LiF/Al(D NC), ITO/CuPc/J03/CBP/TPBi/Alq 3/LiF/Al(D JC) and ITO /CuPc/J03/FNPD/TPBi/Alq 3/LiF/Al(D JF). Here copper phthaloc yan ine (CuPc) acted as hole-injecting layer(HIL), N,N-bis-(1-naphthyl)-N,N-di phenyl-1.1bipheny1-4-4-diamine(NPB) and J03 hole-transporting layers (HTLs) , 4,4'-dicarbazolyl-1,1'-biphenyl (CBP) and FNPD as emitting layers(EMLs), N, arylbenzimidazoles (TPBi) as hole-blocking layer(HBL), and tris(8-quinolinolat o) aluminium complex(Alq 3) as electron-transporting layer(ETL). TPBi applied her e is a good confinement to both charges and excitons, which make the devices emit blue-violet light or iginating from the emitter, CBP and FNPD. Their characteristics have also been i nvestigated. The result shows that the device D NC based on NPB/CBP has the best performance among the three devices. The excellence of D NC is attrib uted to the better hole-transporting ability of NPB as compared with J03, and t he better emitting ability of CBP as compared with FNPD, although the best match ing of energy levels is found in the hole-transporting layer and emitting layer of the device D JF.
基金financially supported by the Joint Funds Project funding from Guangdong Basic and Applied Basic Research Foundation(Grant No.2019B1515120083)the National Natural Science Foundation of China(Grant No.U19A2089)+4 种基金the Key Fundamental Research Project funding from the Shenzhen Science and Technology Innovation Committee(Grant No.JCYJ20200109141014474)the National Key Research and Development Project from the Ministry of Science and Technology of China(Grants Nos.2016YFA0202400 and 2016YFA0202404)the Peacock Team Project from Shenzhen Science and Technology Innovation Committee(Grant No.KQTD2015033110182370)Shenzhen Engineering R&D Center for Flexible Solar Cells project funding from Shenzhen Development and Reform Committee(Grant No.2019-126)the Guangdong-Hong Kong-Macao Joint Laboratory(Grant No.2019B121205001).
文摘There have been huge achievements of all-perovskite tandem solar cells,which recently realized the highest power conversion efficiency of 24.8%.However,the complex device structure and complicated manufacture processes severely restrict the further development of all-perovskite tandem solar cells.In this work,we successfully fabricated high-efficiency hole transport material-free(HTM-free)Sn−Pb alloyed narrow bandgap perovskite solar cells(PSCs)by introducing guanidinium thiocyanate(GASCN)and hydroiodic acid(HI)into the perovskite precursor solution.GASCN and HI play a positive synergy effect during perovskite crystallization process resulting in larger grain size,fewer surface defects,and lower trap density to suppress the Sn^(2+)oxidation degradation.Furthermore,they could effectively adjust the energy level of perovskite materials,reduce the energy level difference between perovskite and ITO resulting in more efficiently transport of free hole charge carriers.As a result,with adding GASCN and HI,the achieved highest power conversion efficiency of HTM-free devices increased from 12.58%to 17.85%,which is one of the highest PCEs among all values reported to date for the HTM-free narrow-bandgap(1.2-1.4 eV)Sn−Pb binary PSCs.Moreover,the optimized device shows improved environmental stability.Our additive strategy manifests a remarkable step towards the facile,cost-efficient fabrication of HTM-free perovskite-based tandem solar cells with both high efficiency and simple fabrication process.
基金supported by the National Natural Science Foundation of China (21822504, 21706070, 21421004, 21636002)Shanghai Science and Technology Committee (17ZR1407400, 17520750100)+2 种基金China Association of Science and Technology (2017QNRC001)Eastern Scholar (TP2016018)the Fundamental Research Funds for the Central Universities (WJ1714007)
文摘The development of p-i-n structured perovskite solar cells(PSCs) requires more extensive explorations on seeking efficient, low cost and stable hole transporting materials(HTMs). Small molecular HTMs are superior to polymeric ones in terms of synthetic reproducibility as well as purity. However, thin films composed of small molecules are usually labile during the solution-based perovskite deposition. Herein, we propose a molecular engineering strategy of incorporating oligothiophene as conjugation bridge to develop robust oligomer HTMs for p-i-n type PSCs. Upon increasing the oligothiophene chain length from α-bithiophene to α-quaterthiophene and α-hexathiophene, their HOMO energy levels remain unchanged, but their solubility in common organic solvents decreased remarkably, thus greatly enhancing their tolerance to the perovskite deposition. The rational design of oligothiophene chain length can effectively tune their optoelectronic properties as well as thin film stability under polar solvent soaking. The best performance is achieved by an α-quaterthiophene based HTM(QT), showing a high efficiency of 17.69% with fill factor of 0.81, which are comparable to those of a commercially available benchmark polymer HTM(poly[bis(4-phenyl)(2,4-dimethylphenyl) amine], PTAA) based devices fabricated under the same conditions. Our developed oligomer system not only provides the definite molecular structures like small molecule-type HTMs, but also exhibits the excellent filmforming like polymer-type HTMs, thus achieving the well-balanced parameters among solvent tolerance, thin film conductivity,and interfacial charge transfer efficiency, especially building up a platform to develop low cost and reproducible efficient HTMs in p-i-n structured perovskite solar cells.
基金financially supported by the National Natural Science Foundation of China NSFC(51702038)the Recruitment Program for Young Professionals+1 种基金the National Key Research and Development Program of China(2017YFA0206600)the National Natural Science Foundation of China(51773045,21772030,51922032,21961160720)for financial support。
文摘Nickel oxide(NiOx)has exhibited great potential as an inorganic hole transport layer(HTL)in perovskite solar cells(PSCs)due to its wide optical bandgap and superior stability.In this study,we have modulated the Ni26 vacancies in NiOx film by controlling deposition temperature in a hot-casting process,resulting the change of coordination structure and charge state of NiOx.Moreover,the change of the HOMO level of NiOx makes it more compatible with perovskite to decrease energy losses and enhance hole carrier injection efficiency.Besides,the defect modulation in the electronic structure of NiOx is beneficial for increasing the electrical conductivity and mobility,which are considered to achieve the balance of charge carrier transport and avoid charge accumulation at the interface between perovskite and HTL effectively.Both experimental analyses and theoretical calculations reveal the increase of nickel vacancy defects change the electronic structure of NiOx by increasing the ratio of Ni3^+/Ni2^+-and improving the p-type characteristics.Accordingly,an optimal deposition temperature at 120℃enabled a 36.24%improvement in the power conversion efficiency compared to that deposited at room temperature(25℃).Therefore,this work provides a facile method to manipulate the electronic structure of NiOx to improve the charge carrier transport and photovoltaic performance of related PSCs.
基金supported by grants from the National Natural Science Foundation of China(Nos. 21704030, 21602115)the financial support from the National 1000 Young Talents Program hosted by Chinathe independent innovation research funding from HUST
文摘Continuous success has been achieved for solution-processed inorganic-organic hybrid perovskite solar cells（PVSCs） in the past several years, in which organic charge transporting materials play an important role. At present, most of the commonly used hole-transporting materials（HTMs） such as spiro-OMeTAD derivatives for PVSCs require additional chemical doping process to ensure sufficient conductivity and shift the Fermi level towards the HOMO level for efficient hole transport and collection. However, this doping process not only increases the complexity and cost of device fabrication, but also decreases the device stability. Thus development of efficient dopant-free HTMs for PVSCs is highly desirable and remains as a major challenge in this field. In this review, we will summarize the recent advances in the molecular design of dopant-free HTMs for PVSCs.
基金the financial support from the National Natural Science Foundation of China(Nos.21572152 and 61575136)funded by Collaborative Innovation Center (CIC) of Suzhou Nano Science and Technologyby the Priority Academic Program Development of the Jiangsu Higher Education Institutions (PAPD)
文摘Organic π-functional molecules are the foundation and basic component of organic optoelectronic devices.For example,for ideal carrier transporting materials,extended π-conjugation and ordered π-πstacking are necessary to enhance the charge mobility and achieve desirable results.As a promising way to convert sunlight into electricity,organometal halide perovskite solar cells（PSCs） have captured a lot of attention due to its predominant merits especially in the aspect of remarkable photovoltaic performance and much potentially low production cost.For conventional planar PSC structure,hole-transporting layer which typically consists of organic π-functional materials plays a key role in suppressing holeelectron pair recombination,promoting charge transporting and ensuring ohmic contact of back electrode.Considering the key roles of HTMs and its soaring progress in recent years,here,we will summarize recent progress in small organic π-functional materials from its diverse functions in PSCs.Besides,aiming to further promote the development of organic π-functional molecules and HTMs,a promising direction toward highly efficient HTMs will also be discussed.
文摘N,N-Di-p-tolylaminophenyl)ethenyl]phenyl}-5-(4-bromophenyl)- 1,3,4-oxadiazole (1) containing triarylamine and 2,5-diaryl-1,3,4-oxadiazole units was prepared by Horner-Witting reactions. The structure of the compound was confirmed by 1H NMR, IR, MS and elemental analyses. The crystal structure of 1 was determined by X-ray diffraction analysis. UV absorption spectra and photoluminescent spectra were measured.
