Heterocyclic compounds play an important role in organic hole transport materials(HTMs)for perovskite solar cells(PSCs).Herein,a series of linear D-π-D HTMs(O-CBz,S-CBz,SO_(2)-CBz)with different dibenzoheterocycles c...Heterocyclic compounds play an important role in organic hole transport materials(HTMs)for perovskite solar cells(PSCs).Herein,a series of linear D-π-D HTMs(O-CBz,S-CBz,SO_(2)-CBz)with different dibenzoheterocycles core(dibenzofuran,dibenzothiophene,dibenzothiophene sulfone)were designed and synthesized,and their applications in PSCs were investigated.The intrinsic properties(CV,UV-vis,hole mobility and conductivity)were systematically investigated,demonstrating that all three materials are suitable HTMs for planar n-i-p type PSCs.Benefiting from the excellent hole mobility and conductivity,good film forming ability,and outstanding charge extraction and transport capability of S-CBz,FAPbI_(3)-based PSCs using S-CBz as HTM achieved a PCE of 25.0%,which is superior to that of Spiro-OMeTAD-based PSCs fabricated under the same conditions(23.9%).Furthermore,due to the interaction between S and Pb^(2+),SCBz-based PSC devices exhibited improved stability.This work demonstrates that dibenzothiophene-based architectures are promising candidates for high-performance HTMs in perovskite solar cell architectures.展开更多
Pipeline transport of hydrogen is one of today’s economic and environmental challenges.In order to find safe and reliable application of both existing gas and build new pipelines,it is essential to carry out tests on...Pipeline transport of hydrogen is one of today’s economic and environmental challenges.In order to find safe and reliable application of both existing gas and build new pipelines,it is essential to carry out tests on full-scale pipeline section,including the potentially more dangerous places than the main pipe,the girth welds.For the investigations,pipeline sections of P355NH steel with girth welds were prepared and exposed to pure hydrogen at twice the maximum allowable operating pressure for 41 days.Subsequently,full-scale burst tests were carried out and specimens were cut and prepared from the typical locations of the failed pipeline sections for mechanical,and macro-and microstructural investigations.The results obtained were evaluated and compared with data from previous full-scale tests on pipeline sections without hydrogen exposure.The results showed differences in the behavior of pipeline sections loaded in different ways,with different characteristics of the materials and the welded joints,both in the cases without hydrogen exposure and in the cases exposed to hydrogen.展开更多
To promote the practices of perovskite photovoltaics,it requires to develop efficient perovskite solar cells(PVSCs)standing long-time operation under the adverse environments.Herein,we demonstrate that the tailor-made...To promote the practices of perovskite photovoltaics,it requires to develop efficient perovskite solar cells(PVSCs)standing long-time operation under the adverse environments.Herein,we demonstrate that the tailor-made conjugated polymers as conductive adhesives stabilized the originally redox-reactive heterointerface between perovskite and metal oxide,facilitating the access of efficient and stable inverted PVSCs.It was revealed that bithiophene and phenyl alternating conjugated polymers with partial glycol chains atop of the metal oxide layer has resulted in effective organic-inorganic hybrid hole transporting bilayers,which allow maintaining efficient hole extraction and transport,meanwhile preventing halide migration to directly contact with the nickel oxide(NiO_(x))layer.As a result,the corresponding inverted PVSCs with the organic-inorganic hole transporting bilayers have achieved an excellent power conversion efficiency of 23.22%,outperforming 20.65% of bare NiO_(x)-based devices.Moreover,the encapsulated PVSCs with organic-inorganic bilayers exhibited the excellent photostability with 91% of the initial efficiency after 1000-h one-sun equivalent illumination in ambient conditions.Overall,this work provides new insights into stabilizing the vulnerable heterointerface for perovskite solar cells.展开更多
Nickel oxide(NiO_(x))has been established as a highly efficient and stable holetransporting layer(HTL)in perovskite solar cells(PSCs).However,existing deposition methods for NiO_(x)have been restricted by high-vacuum ...Nickel oxide(NiO_(x))has been established as a highly efficient and stable holetransporting layer(HTL)in perovskite solar cells(PSCs).However,existing deposition methods for NiO_(x)have been restricted by high-vacuum processes and fail to address the energy level mismatch at the NiO_(x)/perovskite interface,which has impeded the development of PSCs.Accordingly,we explored the application of NiO_(x)as a hybrid HTL through a sol-gel process,where a NiO_(x)film was pre-doped with Ag ions,forming a p/p^(+)homojunction in the NiO_(x)-based inverted PSCs.This innovative approach offers two synergistic advantages,including the enlargement of the built-in electric field for facilitating charge separation,optimizing energy level alignment,and charge transfer efficiency at the interface between the perovskite and HTL.Incorporating this hybrid HTL featuring the p/p^(+)homojunction in the inverted PSCs resulted in a high-power conversion efficiency(PCE)of up to 19.25%,significantly narrowing the efficiency gap compared to traditional n-i-p devices.Furthermore,this innovative strategy for the HTL enhanced the environmental stability to 30 days,maintaining 90%of the initial efficiency.展开更多
Perovskite solar cells(PSCs) have made great progress since 2009 and become the focus of current research. As an important part of PSCs, charge transporting materials play an important role in the performance of the d...Perovskite solar cells(PSCs) have made great progress since 2009 and become the focus of current research. As an important part of PSCs, charge transporting materials play an important role in the performance of the devices. In this review, we introduce the evolution of electron and hole transporting materials in PSCs in recent years and summarize some typical charge transporting materials and their applications in PSCs. For electron transporting materials, metal oxides(TiO_(2), SnO_(2) and ZnO) and organic materials(fullerenes, non-fullerenes and their derivatives)are the most widely used materials in PSCs. For hole transporting materials, small molecule spiro-OMeTAD(2,2’,7,7’-Tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9’-spirobifluorene), polymer PEDOT:PSS(poly(3,4-ethylenedioxythiophene): polystyrene sulfonate), PTAA(poly-[bi(4-phenyl)](2,4,3-trimethylphenyla-mine)), P3 HT(poly(3-hexythiophene)) and inorganic materials(NiOx, CuSCN, CuO) are adopted in PSCs. Finally, different types of charge transporting materials are summarized and their future development is prospected.展开更多
Recent advancements in perovskites’ application as a solar energy harvester have been astonishing. The power conversion efficiency(PCE) of perovskite solar cells(PSCs) is currently reaching parity(>25 percent), an...Recent advancements in perovskites’ application as a solar energy harvester have been astonishing. The power conversion efficiency(PCE) of perovskite solar cells(PSCs) is currently reaching parity(>25 percent), an accomplishment attained over past decades. PSCs are seen as perovskites sandwiched between an electron transporting material(ETM) and a hole transporting material(HTM). As a primary component of PSCs, HTM has been shown to have a considerable effect on solar energy harvesting, carrier extraction and transport, crystallization of perovskite, stability, and price. In PSCs, it is still necessary to use a HTM.While perovskites are capable of conducting holes, they are present in trace amounts, necessitating the use of an HTM layer for efficient charge extraction. In this review, we provide an understanding of the significant forms of HTM accessible(inorganic, polymeric and small molecule-based HTMs), to motivate further research and development of such materials. The identification of additional criteria suggests a significant challenge to high stability and affordability in PSC.展开更多
As a solution to the breaking of pipeline under high axial force,carbon fiber composite pipe with low density and high intensity is applied to deep-sea mining transporting system.Based on the fact that the transportin...As a solution to the breaking of pipeline under high axial force,carbon fiber composite pipe with low density and high intensity is applied to deep-sea mining transporting system.Based on the fact that the transporting pipe is under the forces of gravity,inner liquid,buoyancy as well as hydrodynamic force,geometric nonlinear finite element theory has been applied to analyzing the transporting system.Conclusions can be drawn as follows.Under the interaction of waves and currents,node forces FX and FZ acted by the transporting pipe on the mining vehicle are less than 2 kN,which indicates that waves and currents have little influence on the spatial shape of the transporting pipe and the mining vehicle movement.On the other hand,the horizontal force acting on the mining ship could be as large as 106 830 N,which has great influence on the mining system.展开更多
In this work, we prepared three simple arylamine-based hole transporting materials from commercially available starting materials. The effect of extending z-conjugation length or increasing the number of side groups c...In this work, we prepared three simple arylamine-based hole transporting materials from commercially available starting materials. The effect of extending z-conjugation length or increasing the number of side groups compared with reference compound on the photophysical, electrochemical, hole mobility properties and performance in perovskite solar cells were further studied. It is noted that these two kinds of molecular modifications can significantly lower the HOMO level and improve the hole mobility, thus improving the hole injection from valence band of perovskite. On the other hand, the compound with more side groups showed higher hole injection efficiency due to lower HOMO level and higher hole mo- bility compared with the compound with extending π-conjugation length. The perovskite solar cells with the modified molecules as hole transporting materials showed a higher efficiency of 15.40% and 16.95%, respectively, which is better than that of the reference compound （13.18%）. Moreover, the compound with increasing number of side groups based devices showed comparable photovoltaic performance with that of conventional spiro-OMeTAD （16.87%）.展开更多
In principle,conjugated polymers can work as electron donors and thus as low-cost p-type organic semiconductors to transport holes in photovoltaic devices.With the booming interests in high-efficiency and low-cost sol...In principle,conjugated polymers can work as electron donors and thus as low-cost p-type organic semiconductors to transport holes in photovoltaic devices.With the booming interests in high-efficiency and low-cost solar cells to tackle global climate change and energy shortage,hole transporting materials(HTMs)based on conjugated polymers have received increasing attention in the past decade.In this perspective,recent advances in HTMs for a range of photovoltaic devices including dye-sensitized solar cells(DSSCs),perovskite solar cells(PSCs),and silicon(Si)/organic heterojunction solar cells(HSCs)are summarized and perspectives on their future development are also presented.展开更多
Three novel diketopyrrolopyrrole （DPP） based small organic molecules were synthesized as hole transporting materials for perovskite solar cells. The effects of different donors and zr bridges on the performance of p...Three novel diketopyrrolopyrrole （DPP） based small organic molecules were synthesized as hole transporting materials for perovskite solar cells. The effects of different donors and zr bridges on the performance of perovskite solar cells （PSCs） were discussed. The efficiency of TPADPP-1, TPADPP-2. PTZDPP-2 was 5.10%, 9.85% and 8.16% respectively. Compared to TPADPP-2, the voltage of PTZDPP-2 was higher. Because the electron-donatingability of phenothiazine based donor was larger than that of triphenylamine based donor, the HOMO level of PTZDPP-2 was lower than that of TPADPP-2. The results indicated that the diketopyrrolopyrrole based D-π-A-π-D type small organic molecule might be a promising hole trans- porting material in the perovskite solar cells.展开更多
In this study the performance of organic light-emitting diodes （OLEDs） are enhanced significantly, which is based on dual electron transporting layers （13phen/CuPc）. By adjusting the thicknesses of Bphen and CuPc,...In this study the performance of organic light-emitting diodes （OLEDs） are enhanced significantly, which is based on dual electron transporting layers （13phen/CuPc）. By adjusting the thicknesses of Bphen and CuPc, the maximal luminescence, the maximal current efficiency, and the maximal power efficiency of the device reach 17570 cd/m^2 at 11 V, and 5.39 cd/A and 3.39 lm/W at 3.37 mA/cm^2 respectively, which are enhanced approximately by 33.4%, 39.3%, and 68.9%, respectively, compared with those of the device using Bphen only for an electron transporting layer. These results may provide some valuable references for improving the electron injection and the transportation of OLED.展开更多
Objective Oil-source faults have an important effect on reservoir formation and distribution in shallow formations with non- hydrocarbon generation in oil-rich fault-related basins （Jiang Youlu et al., 2015）. Howev...Objective Oil-source faults have an important effect on reservoir formation and distribution in shallow formations with non- hydrocarbon generation in oil-rich fault-related basins （Jiang Youlu et al., 2015）. However, the fault transporting capacity cannot be evaluated quantitatively at present. Taking the Zhanhua Sag in the Bohai Bay Basin as an example, this work analyzed the factors influencing the transporting capacity of the oil-source faults and proposed a quantitative method for evaluating their transporting capacity.展开更多
In recent years the photovoltaic community has witnessed the unprecedented development of perovskite solar cells（PSCs） as they have taken the lead in emergent photovoltaic technologies. The power conversion efficien...In recent years the photovoltaic community has witnessed the unprecedented development of perovskite solar cells（PSCs） as they have taken the lead in emergent photovoltaic technologies. The power conversion efficiency of this new class of solar cells has been increased to a point where they are beginning to compete with more established technologies. Although PSCs have evolved a variety of structures, the use of hole-transporting materials（HTMs） remains indispensable. Here, an overview of the various types of available HTMs is presented. This includes organic and inorganic HTMs and is presented alongside recent progress in associated aspects of PSCs, including device architectures and fabrication techniques to produce high-quality perovskite films. The structure, electrochemistry, and physical properties of a variety of HTMs are discussed, highlighting considerations for those designing new HTMs. Finally, an outlook is presented to provide more concrete direction for the development and optimization of HTMs for highefficiency 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
The high number of leak events that took place in recent years at a 25.4 cm (10”)Øpipeline transporting anhydrous liquid ammonia, located in the Southeast of Mexico, was the main reason to carry out a numb...The high number of leak events that took place in recent years at a 25.4 cm (10”)Øpipeline transporting anhydrous liquid ammonia, located in the Southeast of Mexico, was the main reason to carry out a number of field studies and laboratory tests that helped establish not only the failure causes but also mitigation and control solutions. The performed activities included direct evaluation at failure sites, total repair programs, metallographic studies and pipeline flexibility analyses. The obtained results were useful to conclude that the failures obeyed a cracking mechanism by Stress Corrosion Cracking (SCC) which was caused by the combined effect of different factors: high stress resistance, high hardness of the base metal with a microstructure prone to brittleness and residual strains originated during the pipeline construction. From the operative, logistic and financial standpoints, it is not feasible to release the stress of approximately 22 km of pipeline. Therefore, the only viable solution is to install a new pipeline with suitable fabrication, construction and installation specifications aimed at preventing the SCC phenomenon.展开更多
Two novel fluorene-based hole transporting materials (HTMs) were synthesized to be used in perovskite solar cells (PSCs). C102 was designed based on C101 by simply linking the two carb on-carbon single bonds to compos...Two novel fluorene-based hole transporting materials (HTMs) were synthesized to be used in perovskite solar cells (PSCs). C102 was designed based on C101 by simply linking the two carb on-carbon single bonds to compose a "dispiro" structure. Their typically similar structures cause them sharing almost the same energy levels. However, their photovoltaic performances are quite different due to the small variations. The PSC that contained the "dispiro" structure, C102, reached a power conversion efficiency (PCE) of 17.4%, while the device contained C101, obtained a lower PCE of 15.5%. Electrochemical properties and Photovoltaic characterization of the two materials have been investigated to explain the result. It is shown that C102 has a stronger ability to transport holes and resist the charge recombination. Thus, the dispiro structure should be more appropriate being used as HTM in PSCs.展开更多
Phosphorous tetrabenzotriazacorrole(TBC)and its two soluble derivatives(TBC-1 and TBC-2)were synthesized and used for the first time as undoped hole transporting materials(HTMs)in MAPbI3 perovskite solar cells(PSCs).T...Phosphorous tetrabenzotriazacorrole(TBC)and its two soluble derivatives(TBC-1 and TBC-2)were synthesized and used for the first time as undoped hole transporting materials(HTMs)in MAPbI3 perovskite solar cells(PSCs).Their performance in PSCs was measured and compared with that of SpiroOMeTAD and phthalocyanine precursor.The fundamental properties related to HTMs are also examined.These novel HTMs are easily prepared,cost-effective,and solution processable.The materials exhibited much higher hole transport mobility and broader light absorption than pristine Spiro-OMeTAD and phthalocyanine precursor.They can work efficiently in the absence of any dopant for devices composed of FTO/cp-TiO2/mp-TiO2/MAPbI3/HTM/Au.The undoped mesoscopic solar cell devices based on TBC exhibited a promising power conversion efficiency(PCE)of up to 16.2%(measured at 100 mWcm2 illumination,AM 1.5 G),together with good long-term stability under ambient conditions.This PCE of 16.2%observed using TBC is remarkably higher than the 11.2%observed using undoped Spiro-OMeTAD and also much better than the 8.70%observed using its phthalocyanine precursor.As to substitution effects,α-substituted TBC-1 was found to be a better HTM thanβ-substituted TBC-2(PCE 11.4%)and unsubstituted TBC-3(PCE 6.81%)under the same conditions.These results provide the basis for further exploiting TBC compounds as a new type of low-cost and effective HTM for PSCs.展开更多
The paper was a truck transporting system that based on system engineering theory and driver, truck-and-train, road and transporting environment were essential factors. It analyzed andstudied nine subsystems consisted...The paper was a truck transporting system that based on system engineering theory and driver, truck-and-train, road and transporting environment were essential factors. It analyzed andstudied nine subsystems consisted of the tfour tactors, ensured running safety, high efficieney and lowconsumption of transporting truck and increased using time of truck and road.展开更多
The key building blocks,tetrachlorinated terrylene diimides and the targeted sila-annulated terrylene diimides(Si-TDIs and 2Si-TDIs)were synthesized for the first time.Single-crystal analysis verified the almost plana...The key building blocks,tetrachlorinated terrylene diimides and the targeted sila-annulated terrylene diimides(Si-TDIs and 2Si-TDIs)were synthesized for the first time.Single-crystal analysis verified the almost planar molecular configurations of both Si-TDIs and 2Si-TDIs.They exhibited intriguing optical properties including red-shifted absorption and near-infrared emission properties with excellent fluorescence quantum yields,as well as precisely controlled HOMO/LUMO energy levels by Si-heteroannulation.The single-crystal organic field-effect transistors based on 2Si-TDI 5a featuring long and branched alkyl chains demonstrated well-balanced ambipolar transporting properties with electron/hole mobilities of 0.10/0.18 cm2 V^(−1)s^(−1).展开更多
This paper investigates the transverse 3:1 internal resonance of an axially transporting nonlinear viscoelastic Euler-Bernoulli beam with a two-frequency parametric excitation caused by a speed perturbation.The Kelvin...This paper investigates the transverse 3:1 internal resonance of an axially transporting nonlinear viscoelastic Euler-Bernoulli beam with a two-frequency parametric excitation caused by a speed perturbation.The Kelvin-Voigt model is introduced to describe the viscoelastic characteristics of the axially transporting beam.The governing equation and the associated boundary conditions are obtained by Newton’s second law.The method of multiple scales is utilized to obtain the steady-state responses.The RouthHurwitz criterion is used to determine the stabilities and bifurcations of the steady-state responses.The effects of the material viscoelastic coefficient on the dynamics of the transporting beam are studied in detail by a series of numerical demonstrations.Interesting phenomena of the steady-state responses are revealed in the 3:1 internal resonance and two-frequency parametric excitation.The approximate analytical method is validated via a differential quadrature method.展开更多
基金supported by the financial support from the National Natural Science Foundation of China(Nos.22279046,22179053)Natural Science Excellent Youth Foundation of Jiangsu Province(No.BK20220112)Special Foundation for Carbon Peak Carbon Neutralization Technology Innovation Program of Jiangsu Province(No.BE2022026-2).
文摘Heterocyclic compounds play an important role in organic hole transport materials(HTMs)for perovskite solar cells(PSCs).Herein,a series of linear D-π-D HTMs(O-CBz,S-CBz,SO_(2)-CBz)with different dibenzoheterocycles core(dibenzofuran,dibenzothiophene,dibenzothiophene sulfone)were designed and synthesized,and their applications in PSCs were investigated.The intrinsic properties(CV,UV-vis,hole mobility and conductivity)were systematically investigated,demonstrating that all three materials are suitable HTMs for planar n-i-p type PSCs.Benefiting from the excellent hole mobility and conductivity,good film forming ability,and outstanding charge extraction and transport capability of S-CBz,FAPbI_(3)-based PSCs using S-CBz as HTM achieved a PCE of 25.0%,which is superior to that of Spiro-OMeTAD-based PSCs fabricated under the same conditions(23.9%).Furthermore,due to the interaction between S and Pb^(2+),SCBz-based PSC devices exhibited improved stability.This work demonstrates that dibenzothiophene-based architectures are promising candidates for high-performance HTMs in perovskite solar cell architectures.
基金supported by the European Union and the Hungarian State,co-financed by the European Structural and Investment Funds in the framework of the GINOP-2.3.4-15-2016-00004 project。
文摘Pipeline transport of hydrogen is one of today’s economic and environmental challenges.In order to find safe and reliable application of both existing gas and build new pipelines,it is essential to carry out tests on full-scale pipeline section,including the potentially more dangerous places than the main pipe,the girth welds.For the investigations,pipeline sections of P355NH steel with girth welds were prepared and exposed to pure hydrogen at twice the maximum allowable operating pressure for 41 days.Subsequently,full-scale burst tests were carried out and specimens were cut and prepared from the typical locations of the failed pipeline sections for mechanical,and macro-and microstructural investigations.The results obtained were evaluated and compared with data from previous full-scale tests on pipeline sections without hydrogen exposure.The results showed differences in the behavior of pipeline sections loaded in different ways,with different characteristics of the materials and the welded joints,both in the cases without hydrogen exposure and in the cases exposed to hydrogen.
基金funded by the National Natural Science Foundation of China(No.22125901)the National Key Research and Development Program of China(No.2019YFA0705900)the Fundamental Research Funds for the Central Universities(No.226-2023-00113)。
文摘To promote the practices of perovskite photovoltaics,it requires to develop efficient perovskite solar cells(PVSCs)standing long-time operation under the adverse environments.Herein,we demonstrate that the tailor-made conjugated polymers as conductive adhesives stabilized the originally redox-reactive heterointerface between perovskite and metal oxide,facilitating the access of efficient and stable inverted PVSCs.It was revealed that bithiophene and phenyl alternating conjugated polymers with partial glycol chains atop of the metal oxide layer has resulted in effective organic-inorganic hybrid hole transporting bilayers,which allow maintaining efficient hole extraction and transport,meanwhile preventing halide migration to directly contact with the nickel oxide(NiO_(x))layer.As a result,the corresponding inverted PVSCs with the organic-inorganic hole transporting bilayers have achieved an excellent power conversion efficiency of 23.22%,outperforming 20.65% of bare NiO_(x)-based devices.Moreover,the encapsulated PVSCs with organic-inorganic bilayers exhibited the excellent photostability with 91% of the initial efficiency after 1000-h one-sun equivalent illumination in ambient conditions.Overall,this work provides new insights into stabilizing the vulnerable heterointerface for perovskite solar cells.
基金funded in part by the National Natural Science Foundation of China(62204210)the Natural Science Foundation of Jiangsu Province(BK20220284)+6 种基金the Natural Science Foundation of the Higher Education Institutions of Jiangsu Province(22KJB510013)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China Program(19KJB510059)the Suzhou Science and Technology Development Planning Project:Key Industrial Technology Innovation(SYG201924)University Research Development Fund(RDF-17-01-13)the Key Program Special Fund in XJTLU(KSF-T-03,KSFA-07)partially supported by the XJTLU AI University Research CentreJiangsu(Provincial)Data Science and Cognitive Computational Engineering Research Centre at XJTLU
文摘Nickel oxide(NiO_(x))has been established as a highly efficient and stable holetransporting layer(HTL)in perovskite solar cells(PSCs).However,existing deposition methods for NiO_(x)have been restricted by high-vacuum processes and fail to address the energy level mismatch at the NiO_(x)/perovskite interface,which has impeded the development of PSCs.Accordingly,we explored the application of NiO_(x)as a hybrid HTL through a sol-gel process,where a NiO_(x)film was pre-doped with Ag ions,forming a p/p^(+)homojunction in the NiO_(x)-based inverted PSCs.This innovative approach offers two synergistic advantages,including the enlargement of the built-in electric field for facilitating charge separation,optimizing energy level alignment,and charge transfer efficiency at the interface between the perovskite and HTL.Incorporating this hybrid HTL featuring the p/p^(+)homojunction in the inverted PSCs resulted in a high-power conversion efficiency(PCE)of up to 19.25%,significantly narrowing the efficiency gap compared to traditional n-i-p devices.Furthermore,this innovative strategy for the HTL enhanced the environmental stability to 30 days,maintaining 90%of the initial efficiency.
基金financially supported by the National Natural Science Foundation of China (Nos.61922060,61775156,61905173 and U1710115)Key Research and Development (International Cooperation) Program of Shanxi Province (No.201803D421044)+2 种基金the Natural Science Foundation of Shanxi Province (No.201801D221029)the Henry Fok Education Foundation Young Teachers fund,the Young Sanjin Scholars Program,the Platform and Base Special Project of Shanxi Province (No.201805D131012-3)the Graduate Innovation Project of Shanxi Province (No.2020BY117)。
文摘Perovskite solar cells(PSCs) have made great progress since 2009 and become the focus of current research. As an important part of PSCs, charge transporting materials play an important role in the performance of the devices. In this review, we introduce the evolution of electron and hole transporting materials in PSCs in recent years and summarize some typical charge transporting materials and their applications in PSCs. For electron transporting materials, metal oxides(TiO_(2), SnO_(2) and ZnO) and organic materials(fullerenes, non-fullerenes and their derivatives)are the most widely used materials in PSCs. For hole transporting materials, small molecule spiro-OMeTAD(2,2’,7,7’-Tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9’-spirobifluorene), polymer PEDOT:PSS(poly(3,4-ethylenedioxythiophene): polystyrene sulfonate), PTAA(poly-[bi(4-phenyl)](2,4,3-trimethylphenyla-mine)), P3 HT(poly(3-hexythiophene)) and inorganic materials(NiOx, CuSCN, CuO) are adopted in PSCs. Finally, different types of charge transporting materials are summarized and their future development is prospected.
文摘Recent advancements in perovskites’ application as a solar energy harvester have been astonishing. The power conversion efficiency(PCE) of perovskite solar cells(PSCs) is currently reaching parity(>25 percent), an accomplishment attained over past decades. PSCs are seen as perovskites sandwiched between an electron transporting material(ETM) and a hole transporting material(HTM). As a primary component of PSCs, HTM has been shown to have a considerable effect on solar energy harvesting, carrier extraction and transport, crystallization of perovskite, stability, and price. In PSCs, it is still necessary to use a HTM.While perovskites are capable of conducting holes, they are present in trace amounts, necessitating the use of an HTM layer for efficient charge extraction. In this review, we provide an understanding of the significant forms of HTM accessible(inorganic, polymeric and small molecule-based HTMs), to motivate further research and development of such materials. The identification of additional criteria suggests a significant challenge to high stability and affordability in PSC.
基金Project(50975290) supported by the National Natural Science Foundation of ChinaProject(2011QNZT057) supported by the Basic Operational Cost of Special Research Funding of Central Universities in ChinaProject(11JJ5028) supported by Hunan Provincial Natural Science Foundation,China
文摘As a solution to the breaking of pipeline under high axial force,carbon fiber composite pipe with low density and high intensity is applied to deep-sea mining transporting system.Based on the fact that the transporting pipe is under the forces of gravity,inner liquid,buoyancy as well as hydrodynamic force,geometric nonlinear finite element theory has been applied to analyzing the transporting system.Conclusions can be drawn as follows.Under the interaction of waves and currents,node forces FX and FZ acted by the transporting pipe on the mining vehicle are less than 2 kN,which indicates that waves and currents have little influence on the spatial shape of the transporting pipe and the mining vehicle movement.On the other hand,the horizontal force acting on the mining ship could be as large as 106 830 N,which has great influence on the mining system.
基金supported by the National Basic Research Program of China (No. 2015CB932200)the CAS-Iranian Vice Presidency for Science and Technology Joint Research Project (No. 116134KYSB20160130)+2 种基金the Natural Science Foundation of Anhui Province (No. 1508085SMF224)the National Natural Science Foundation of China (No. 51474201)the External Cooperation Program of BIC, Chinese Academy of Sciences (No. GJHZ1607)
文摘In this work, we prepared three simple arylamine-based hole transporting materials from commercially available starting materials. The effect of extending z-conjugation length or increasing the number of side groups compared with reference compound on the photophysical, electrochemical, hole mobility properties and performance in perovskite solar cells were further studied. It is noted that these two kinds of molecular modifications can significantly lower the HOMO level and improve the hole mobility, thus improving the hole injection from valence band of perovskite. On the other hand, the compound with more side groups showed higher hole injection efficiency due to lower HOMO level and higher hole mo- bility compared with the compound with extending π-conjugation length. The perovskite solar cells with the modified molecules as hole transporting materials showed a higher efficiency of 15.40% and 16.95%, respectively, which is better than that of the reference compound （13.18%）. Moreover, the compound with increasing number of side groups based devices showed comparable photovoltaic performance with that of conventional spiro-OMeTAD （16.87%）.
基金supported by the National Natural Science Foundation of China(Nos.21774015 and 21975027)NSFC-MAECI(No.51861135202).
文摘In principle,conjugated polymers can work as electron donors and thus as low-cost p-type organic semiconductors to transport holes in photovoltaic devices.With the booming interests in high-efficiency and low-cost solar cells to tackle global climate change and energy shortage,hole transporting materials(HTMs)based on conjugated polymers have received increasing attention in the past decade.In this perspective,recent advances in HTMs for a range of photovoltaic devices including dye-sensitized solar cells(DSSCs),perovskite solar cells(PSCs),and silicon(Si)/organic heterojunction solar cells(HSCs)are summarized and perspectives on their future development are also presented.
基金the National Key Research Development Program of China(2016YFA0602900)the National Natural Science Foundation of China(21272079,21572069)+1 种基金the Science and Technology Planning Project of Guangdong Province,China(2013B010405003)the fund from the Guangzhou Science and Technology Project,China(201607010265)
文摘Three novel diketopyrrolopyrrole （DPP） based small organic molecules were synthesized as hole transporting materials for perovskite solar cells. The effects of different donors and zr bridges on the performance of perovskite solar cells （PSCs） were discussed. The efficiency of TPADPP-1, TPADPP-2. PTZDPP-2 was 5.10%, 9.85% and 8.16% respectively. Compared to TPADPP-2, the voltage of PTZDPP-2 was higher. Because the electron-donatingability of phenothiazine based donor was larger than that of triphenylamine based donor, the HOMO level of PTZDPP-2 was lower than that of TPADPP-2. The results indicated that the diketopyrrolopyrrole based D-π-A-π-D type small organic molecule might be a promising hole trans- porting material in the perovskite solar cells.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 60906022 and 60876046)the Tianjin Natural Science Foundation of China (Grant No. 10JCYBJC01100)
文摘In this study the performance of organic light-emitting diodes （OLEDs） are enhanced significantly, which is based on dual electron transporting layers （13phen/CuPc）. By adjusting the thicknesses of Bphen and CuPc, the maximal luminescence, the maximal current efficiency, and the maximal power efficiency of the device reach 17570 cd/m^2 at 11 V, and 5.39 cd/A and 3.39 lm/W at 3.37 mA/cm^2 respectively, which are enhanced approximately by 33.4%, 39.3%, and 68.9%, respectively, compared with those of the device using Bphen only for an electron transporting layer. These results may provide some valuable references for improving the electron injection and the transportation of OLED.
基金granted by the National Natural Science Foundation of China(grant No.41672131)Fundamental Research Funds for the Central Universities(grant No.16CX06045A)
文摘Objective Oil-source faults have an important effect on reservoir formation and distribution in shallow formations with non- hydrocarbon generation in oil-rich fault-related basins （Jiang Youlu et al., 2015）. However, the fault transporting capacity cannot be evaluated quantitatively at present. Taking the Zhanhua Sag in the Bohai Bay Basin as an example, this work analyzed the factors influencing the transporting capacity of the oil-source faults and proposed a quantitative method for evaluating their transporting capacity.
基金financial support from the Natural Science Foundation of China (grant numbers: 51661135021, 21606039, 91233201, and 21276044)
文摘In recent years the photovoltaic community has witnessed the unprecedented development of perovskite solar cells（PSCs） as they have taken the lead in emergent photovoltaic technologies. The power conversion efficiency of this new class of solar cells has been increased to a point where they are beginning to compete with more established technologies. Although PSCs have evolved a variety of structures, the use of hole-transporting materials（HTMs） remains indispensable. Here, an overview of the various types of available HTMs is presented. This includes organic and inorganic HTMs and is presented alongside recent progress in associated aspects of PSCs, including device architectures and fabrication techniques to produce high-quality perovskite films. The structure, electrochemistry, and physical properties of a variety of HTMs are discussed, highlighting considerations for those designing new HTMs. Finally, an outlook is presented to provide more concrete direction for the development and optimization of HTMs for highefficiency 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.
文摘The high number of leak events that took place in recent years at a 25.4 cm (10”)Øpipeline transporting anhydrous liquid ammonia, located in the Southeast of Mexico, was the main reason to carry out a number of field studies and laboratory tests that helped establish not only the failure causes but also mitigation and control solutions. The performed activities included direct evaluation at failure sites, total repair programs, metallographic studies and pipeline flexibility analyses. The obtained results were useful to conclude that the failures obeyed a cracking mechanism by Stress Corrosion Cracking (SCC) which was caused by the combined effect of different factors: high stress resistance, high hardness of the base metal with a microstructure prone to brittleness and residual strains originated during the pipeline construction. From the operative, logistic and financial standpoints, it is not feasible to release the stress of approximately 22 km of pipeline. Therefore, the only viable solution is to install a new pipeline with suitable fabrication, construction and installation specifications aimed at preventing the SCC phenomenon.
基金the National Natural Science Foundation of China(Nos.51661135021,21606039,21507008,91233201,and 21276044)for financial support
文摘Two novel fluorene-based hole transporting materials (HTMs) were synthesized to be used in perovskite solar cells (PSCs). C102 was designed based on C101 by simply linking the two carb on-carbon single bonds to compose a "dispiro" structure. Their typically similar structures cause them sharing almost the same energy levels. However, their photovoltaic performances are quite different due to the small variations. The PSC that contained the "dispiro" structure, C102, reached a power conversion efficiency (PCE) of 17.4%, while the device contained C101, obtained a lower PCE of 15.5%. Electrochemical properties and Photovoltaic characterization of the two materials have been investigated to explain the result. It is shown that C102 has a stronger ability to transport holes and resist the charge recombination. Thus, the dispiro structure should be more appropriate being used as HTM in PSCs.
基金the financial support from the National Key Research and Development Project funding from the Ministry of Science and Technology of China(Grants nos.2016YFA0202400 and 2016YFA0202404)the Peacock Team Project funding from Shenzhen Science and Technology Innovation Committee(Grant no.KQTD2015033110182370)+1 种基金the Shenzhen Engineering R&D Center for Flexible Solar Cells project funding from Shenzhen Development and Reform Committee(Grant no.2019-126)Hebei Provincial Hundred Talents Plan(Contract E2013100005)。
文摘Phosphorous tetrabenzotriazacorrole(TBC)and its two soluble derivatives(TBC-1 and TBC-2)were synthesized and used for the first time as undoped hole transporting materials(HTMs)in MAPbI3 perovskite solar cells(PSCs).Their performance in PSCs was measured and compared with that of SpiroOMeTAD and phthalocyanine precursor.The fundamental properties related to HTMs are also examined.These novel HTMs are easily prepared,cost-effective,and solution processable.The materials exhibited much higher hole transport mobility and broader light absorption than pristine Spiro-OMeTAD and phthalocyanine precursor.They can work efficiently in the absence of any dopant for devices composed of FTO/cp-TiO2/mp-TiO2/MAPbI3/HTM/Au.The undoped mesoscopic solar cell devices based on TBC exhibited a promising power conversion efficiency(PCE)of up to 16.2%(measured at 100 mWcm2 illumination,AM 1.5 G),together with good long-term stability under ambient conditions.This PCE of 16.2%observed using TBC is remarkably higher than the 11.2%observed using undoped Spiro-OMeTAD and also much better than the 8.70%observed using its phthalocyanine precursor.As to substitution effects,α-substituted TBC-1 was found to be a better HTM thanβ-substituted TBC-2(PCE 11.4%)and unsubstituted TBC-3(PCE 6.81%)under the same conditions.These results provide the basis for further exploiting TBC compounds as a new type of low-cost and effective HTM for PSCs.
文摘The paper was a truck transporting system that based on system engineering theory and driver, truck-and-train, road and transporting environment were essential factors. It analyzed andstudied nine subsystems consisted of the tfour tactors, ensured running safety, high efficieney and lowconsumption of transporting truck and increased using time of truck and road.
基金This work was financially supported by the National Natural Science Foundation of China(NSFC,Nos.21901138,21790361 and 22122503)the Shandong Provincial Natural Science Foundation(No.ZR2019ZD50)China Fundamental Research Funds for the Central Universities(No.2-9-2020-041).
文摘The key building blocks,tetrachlorinated terrylene diimides and the targeted sila-annulated terrylene diimides(Si-TDIs and 2Si-TDIs)were synthesized for the first time.Single-crystal analysis verified the almost planar molecular configurations of both Si-TDIs and 2Si-TDIs.They exhibited intriguing optical properties including red-shifted absorption and near-infrared emission properties with excellent fluorescence quantum yields,as well as precisely controlled HOMO/LUMO energy levels by Si-heteroannulation.The single-crystal organic field-effect transistors based on 2Si-TDI 5a featuring long and branched alkyl chains demonstrated well-balanced ambipolar transporting properties with electron/hole mobilities of 0.10/0.18 cm2 V^(−1)s^(−1).
基金Project supported by the National Natural Science Foundation of China (Nos.12002142,1187215951976087)+1 种基金the National Natural Science Foundation of Shanghai of China (No.21ZR1462500)the Natural Science Foundation of Shandong Province of China (No.ZR2021QB137)。
文摘This paper investigates the transverse 3:1 internal resonance of an axially transporting nonlinear viscoelastic Euler-Bernoulli beam with a two-frequency parametric excitation caused by a speed perturbation.The Kelvin-Voigt model is introduced to describe the viscoelastic characteristics of the axially transporting beam.The governing equation and the associated boundary conditions are obtained by Newton’s second law.The method of multiple scales is utilized to obtain the steady-state responses.The RouthHurwitz criterion is used to determine the stabilities and bifurcations of the steady-state responses.The effects of the material viscoelastic coefficient on the dynamics of the transporting beam are studied in detail by a series of numerical demonstrations.Interesting phenomena of the steady-state responses are revealed in the 3:1 internal resonance and two-frequency parametric excitation.The approximate analytical method is validated via a differential quadrature method.
