We synthesize and compare four near-infrared absorbing fused-ring electron acceptors named as nTTIC(n=2,3,4,and 5),based on different number of thieno[3,2-b]thiophene(TT)unit as the electron-donating core.With increas...We synthesize and compare four near-infrared absorbing fused-ring electron acceptors named as nTTIC(n=2,3,4,and 5),based on different number of thieno[3,2-b]thiophene(TT)unit as the electron-donating core.With increasing the TT unit,absorption spectrum of the TTIC series red shifts,and the highest occupied molecular orbital(HOMO)upshifts notably.It is worth noting that 4TTIC and 5TTIC exhibit absorption edges approaching 1100 nm,which is the photoresponse limit of solar cells based on crystal silicon.When the TTIC series acceptors are blended with polymer donor PM6,the binary-blend organic solar cells based on 3TTIC show the best power conversion efficiency(PCE)of 13.1%.In contrast,2TTIC-based devices exhibit relatively lower PCE of 8.32%,mainly caused by the larger energy loss and blue-shifted absorption.Due to insufficient driving force of charge separation caused by very high HOMO,4TTIC and 5TTIC show poor PCEs lower than 3%.展开更多
By employing the asymmetric end-group engineering,an asymmetric nonfused-ring electron acceptor(NFREA)was designed and synthesized.Compared with the symmetric analogs(NoCA-17 and NoCA-18),NoCA-19 possesses broader lig...By employing the asymmetric end-group engineering,an asymmetric nonfused-ring electron acceptor(NFREA)was designed and synthesized.Compared with the symmetric analogs(NoCA-17 and NoCA-18),NoCA-19 possesses broader light absorption range,more coplanarπ-conjugated backbone,and appropriate crystallinity according to the experimental and theoretical results.The organic solar cells based on J52:NoCA-19 exhibited a power conversion efficiency as high as 12.26%,which is much higher than those of J52:NoCA-17(9.50%)and J52:NoCA-18(11.77%),mainly due to more efficient exciton dissociation,better and balanced charge mobility,suppressed recombination loss,shorter charge extraction time,longer charge carrier lifetimes,and more favorable blend film morphology.These findings demonstrate the great potential of asymmetric end-group engineering in exploring low-cost and high-performance NFREAs.展开更多
Fullerene derivatives are classic electron acceptor materials for organic solar cells (Oscs) but possess some intrinsic drawbacks such as weak visiblelightabsorption,limitedoptoelectronic property tunability,dificult ...Fullerene derivatives are classic electron acceptor materials for organic solar cells (Oscs) but possess some intrinsic drawbacks such as weak visiblelightabsorption,limitedoptoelectronic property tunability,dificult purification and photochemical/morphological instability.Fullereneacceptors area bottleneck restricting further development of this field. Ourgroup pioneered the exploration of novel nonfulerene acceptors in China in 2006,andinitiated the research of two representative acceptor systems, rylene dimide polymer and fused-ring electron acceptor (FREA).FREA breaks the theoreticalefficiencylimit of fullerene-based OsCs (-13%) and promotes the whole field to an unprecedented prosperity with efficiency of 20%, heraldinga nonfullerene era for OsCs.In this review, we revisit 15-year nonfullerene exploration journey,summarize the design principles,molecular engineeringstrategies, physical mechanisms and device applications of these two nonfullerene acceptor systems, and propose some possible researchtopics in the nearfuture.展开更多
We propose a strategy to improve performance of unidirectionally extended fused-ring electron acceptors by using pyrrolo[3,2-b]pyrrole to replace pyrrole ring, and design two asymmetric nonfullerene acceptors 1PIC and...We propose a strategy to improve performance of unidirectionally extended fused-ring electron acceptors by using pyrrolo[3,2-b]pyrrole to replace pyrrole ring, and design two asymmetric nonfullerene acceptors 1PIC and 2PIC. Replacing pyrrole in 1PIC with pyrrolo[3,2-b]pyrrole remarkably red-shifts absorption peak by 109 nm, elevates the HOMO and LUMO energy levels, and improves electron mobility. The photovoltaic devices based on blend of PM6 donor and 2PIC acceptor exhibit power conversion efficiency as high as 12.6%, which is much higher than that of PM6:1PIC (3.53%), due to more efficient exciton generation and dissociation, faster and more balanced carrier transport and less charge recombination.展开更多
The power conversion efficiencies(PCEs)of organic solar cells(OSCs)have improved considerably in recent years with the development of fused-ring electron acceptors(FREAs).Currently,FREAs-based OSCs have achieved high ...The power conversion efficiencies(PCEs)of organic solar cells(OSCs)have improved considerably in recent years with the development of fused-ring electron acceptors(FREAs).Currently,FREAs-based OSCs have achieved high PCEs of over 19%in single-junction OSCs.Whereas the relatively high synthetic complexity and the low yield of FREAs typically result in high production costs,hindering the commercial application of OSCs.In contrast,noncovalently fused-ring electron acceptors(NFREAs)can compensate for the shortcomings of FREAs and facilitate large-scale industrial production by virtue of the simple structure,facile synthesis,high yield,low cost,and reasonable efficiency.At present,OSCs based on NFREAs have exceeded the PCEs of 15%and are expected to reach comparable efficiency as FREAs-based OSCs.Here,recent advances in NFREAs in this review provide insight into improving the performance of OSCs.In particular,this paper focuses on the effect of the chemical structures of NFREAs on the molecule conformation,aggregation,and packing mode.Various molecular design strategies,such as core,side-chain,and terminal group engineering,are presented.In addition,some novel polymer acceptors based on NFREAs for all-polymer OSCs are also introduced.In the end,the paper provides an outlook on developing efficient,stable,and low-cost NFREAs for achieving commercial applications.展开更多
Organic solar cells(OSCs)have attracted extensive attention from both academia and industry in recent years due to their remarkable improvement in power conversion efficiency(PCE).However,the Golden Triangle(the balan...Organic solar cells(OSCs)have attracted extensive attention from both academia and industry in recent years due to their remarkable improvement in power conversion efficiency(PCE).However,the Golden Triangle(the balance of efficiency-stability-cost)required for large-scale industrialization of OSCs still remains a great challenge.Here,a new nonfused-ring electron acceptor(NFREA)BF and its polymerized counterpart PBF were designed and synthesized,and their photovoltaic performance,storage stability and material cost were systematically investigated.When blended with a widely-used polymer donor PBDB-T,the PBFbased all-polymer solar cell(all-PSC)displayed a record high PCE of 12.61%for polymerized NFREAs(PNFREAs)with an excellent stability(95.2%of initial PCE after 800 h storage),superior to the BF counterpart.Impressively,PBF-based allPSC possesses the highest industrial figure-of-merit(i-FOM)value of 0.309 based on an efficiency-stability-cost evaluation,in comparison to several representative OSC systems(such as PM6:Y6 and PBDB-T:PZ1).This work provides an insight into the balance of efficiency,stability,and cost,and also indicates that the PNFREAs are promising materials toward the commercial application of OSCs.展开更多
A new fused-ring electron acceptor FNIC3 with dynamics controlled aggregation behavior was synthesized.FNIC3 shows strong absorption in 600–900 nm,HOMO/LUMO energy levels of−5.59/−4.04 eV,and electron mobility of 1.2...A new fused-ring electron acceptor FNIC3 with dynamics controlled aggregation behavior was synthesized.FNIC3 shows strong absorption in 600–900 nm,HOMO/LUMO energy levels of−5.59/−4.04 eV,and electron mobility of 1.2×10^(−3) cm^(2) V^(−1) s^(−1).The aggregation of FNIC3 shows strong dependency on film formation time.Prolongation of film formation time promotes the crystallization of FNIC3,leading to improved crystallinity and enlarged aggregate sizes.Aggregation of FNIC3 significantly influences the photovoltaic device parameters.Appropriate aggregation red-shifts the absorption and improves the mobilities of the blend,which contributes to high photocurrent and fill factor thus high power conversion efficiency(PCE).Overaggregation leads to increased nonradiative energy loss and insufficient charge generation,resulting in decreased open-circuit voltage and short-circuit current density.The blends based on PM6:FNIC3 fabricated under proper film formation time exhibit a PCE of 12.3%,higher than those fabricated under short and long film formation time(10.0–10.5%).展开更多
Comprehensive Summary By employing thiazole and 4-chlorothiazole as the A′units,two A-D-A′-D-A type nonfused-ring electron acceptors(NFREAs)Tz-H and Tz-Cl were designed and synthesized.Replacing thiazole in Tz-H wit...Comprehensive Summary By employing thiazole and 4-chlorothiazole as the A′units,two A-D-A′-D-A type nonfused-ring electron acceptors(NFREAs)Tz-H and Tz-Cl were designed and synthesized.Replacing thiazole in Tz-H with 4-chlorothiazole can not only remarkably shorten the synthetic route through C—H direct arylation but also enhance molecular planarity with the simultaneous incorporation of S…N and S…Cl noncovalently conformational locks(NoCLs).The photovoltaic devices based on PM6:Tz-Cl exhibited a power conversion efficiency as high as 11.10%,much higher than that of PM6:Tz-H(6.41%),mainly due to more efficient exciton dissociation,better and more balanced carrier mobility,less charge recombination,and more favorable morphology.These findings demonstrate the great potential of NoCLs in achieving low-cost and high-performance NFREAs.展开更多
The performance of tin-based perovskite solar cells has been substantially hampered by voltage loss caused by energy level mismatch,charge recombination,energetic disorder,and other issues.Here,a fused-ring electron a...The performance of tin-based perovskite solar cells has been substantially hampered by voltage loss caused by energy level mismatch,charge recombination,energetic disorder,and other issues.Here,a fused-ring electron acceptor based on indacenodithiophene(IDIC)was for the first time introduced as a transition layer between a tin-based perovskite layer and a C 60 electron transport layer,leading to better matched energy levels in the device.In addition,coordination interactions between IDIC and perovskite improved the latter's crystallinity.The introduction of IDIC raised the power conversion efficiency from 8.98%to 11.5%and improved the device's stability.The decomposition mechanism of tin-based perovskite was also revealed by detecting the optical properties of perovskite microdomains through innovative integration of confocal laser scanning microscopy and photoluminescence spectroscopy.展开更多
High-voltage lithium(Li)metal batteries(LMBs)face substantial challenges,including Li dendrite growth and instability in high-voltage cathodes such as LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)(NCM811),which impede their practic...High-voltage lithium(Li)metal batteries(LMBs)face substantial challenges,including Li dendrite growth and instability in high-voltage cathodes such as LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)(NCM811),which impede their practical applications and long-term stability.To address these challenges,tris(pentafluorophenyl)borane additive as an electron acceptor is introduced into an ethyl methyl carbonate/fluoroethylene carbonate-based electrolyte.This approach effectively engineers robust dual interfaces on the Li metal anode and the NCM811 cathode,thereby mitigating dendritic growth of Li and enhancing the stability of the cathode.This additive-driven strategy enables LMBs to operate at ultra-high voltages up to 4.7 V.Consequently,Li||Cu cells achieve a coulombic efficiency of 98.96%,and Li||Li symmetric cells extend their cycle life to an impressive 4000 h.Li||NCM811 full cells maintain a high capacity retention of 87.8%after 100 cycles at 4.7 V.Additionally,Li||LNMO full cells exhibit exceptional rate capability,delivering 132.2 mAh g^(-1)at 10 C and retaining 95.0%capacity after 250 cycles at 1 C and 5 V.As a result,NCM811||graphite pouch cells maintain a 93.4%capacity retention after 1100 cycles at 1 C.These findings underscore the efficacy of additive engineering in addressing Li dendrite formation and instability of cathode under high voltage,thereby paving the road for durable,high-performance LMBs.展开更多
Developing narrow-bandgap organic semiconductors is important to facilitate the advancement of organic photovoltaics(OPVs). Herein, two near-infrared non-fused ring acceptors(NIR NFRAs), PTBFTT-F and PTBFTT-Cl have be...Developing narrow-bandgap organic semiconductors is important to facilitate the advancement of organic photovoltaics(OPVs). Herein, two near-infrared non-fused ring acceptors(NIR NFRAs), PTBFTT-F and PTBFTT-Cl have been developed with A-π_A-π_D-D-π_D-π_A-A non-fused structures. It is revealed that the introduction of electron deficient π-bridge(π_A) and multiple intramolecular noncovalent interactions effectively retained the structural planarity and intramolecular charge transfer of NFRAs, extending strong NIR photon absorption up to 950 nm. Further, the chlorinated acceptor, with the enlarged π-surface compared to the fluorinated counterpart, promoted not only molecular stacking in solid, but also the desirable photochemical stability in ambient, which are helpful to thereby improve the exciton and charge dynamics for the corresponding OPVs. Overall, this work provides valuable insights into the design of NIR organic semiconductors.展开更多
Low-cost photovoltaic materials are essential for realizing large-scale commercial applications of organic solar cells(OSCs).However,highly efficient OSCs based on low-cost photovoltaic materials are scarce due to a d...Low-cost photovoltaic materials are essential for realizing large-scale commercial applications of organic solar cells(OSCs).However,highly efficient OSCs based on low-cost photovoltaic materials are scarce due to a deficiency in understanding the structure-property relationship.Herein,we investigated two low-cost terthiophene-based electron acceptors,namely,3TC8 and 3TEH,with 3,4-bis(octan-3-yloxy)thiophene,differing only in the alkylated thiophene-bridges.Both acceptors exhibit low optical gaps(∼1.43 eV)and possess deep highest occupied molecular orbital(HOMO)levels(∼−5.8 eV).Notably,the single-crystal structure of 3TEH demonstrates highly planar conjugated backbone and strongπ-πstacking between intermolecular terminal groups,attributed to the presence of the bulky alkylated noncovalently conformational locks.Upon utilizing both acceptors to fabricate OSCs,the 3TC8-based device exhibited a power conversion efficiency(PCE)of 11.1%,while the 3TEH-based OSC demonstrated an excellent PCE of 14.4%.This PCE is the highest among OSCs based on terthiophene-containing electron acceptors.These results offer a new strategy for designing low-cost electron acceptors for highly efficient OSCs.展开更多
Sulfate and nitrate reducing bacteria are important culprits for microbiologically influenced corrosion(MIC)using sulfate and nitrate as electron acceptors,respectively.Sulfate and nitrate hold different standard elec...Sulfate and nitrate reducing bacteria are important culprits for microbiologically influenced corrosion(MIC)using sulfate and nitrate as electron acceptors,respectively.Sulfate and nitrate hold different standard electrode potentials,which may lead to differences in corrosion,but their effects on corrosion by the same bacteria have not been reported.The corrosion of Q235 steel affected by Pseudodesulfovibrio cashew(P.cashew)in the sulfate and nitrate media under carbon starvation was studied.It was found that sulfate and nitrate did not lead to differences in corrosion under abiotic conditions.However,P.cashew promoted corrosion in both cases,and the consumption of H_(2)was the main mechanism for MIC.In addition,corrosion was more severe in the sulfate media.The higher corrosivity of P.cashew with sulfate as the electron acceptor is closely related to the higher number of sessile cells in the biofilm,higher bacterial motility,more hydrogen production pathways,and the increased gene expression of enzymes related to energy synthesis.展开更多
A binary-mixed electron transport layer(ETL)has been reported for constructing solution-processable near-infrared organic light-emitting diodes(NIR OLEDs).Relative to the single-component ETL,the binarymixed ETL compo...A binary-mixed electron transport layer(ETL)has been reported for constructing solution-processable near-infrared organic light-emitting diodes(NIR OLEDs).Relative to the single-component ETL,the binarymixed ETL composed of PDINN:TPBi can enhance the carrier transport capacity,reduce device impedance,and weaken fiuorescence quenching of the emitting layer.By carefully selecting an appropriate luminescent material Y5(a nonfullerene electron acceptor in organic solar cells)and precisely fine-tuning the molecular aggregation in active layer using a mixed solvent,the morphology is optimized and luminescence performance is enhanced,resulting in efficient NIR OLEDs with an emission peak at 890 nm.The experiment showcases a Y5-based near-infrared OLED with a maximum radiance of 34.9 W sr^(-1)m^(-2)and a maximum external quantum efficiency of 0.50%,which is among the highest values reported for nondoped fiuorescent NIR OLEDs with an emission peak over 850 nm.展开更多
Two simple electron acceptors based on unfused bithiophene core and 1,1-dicyanomethylene-3-indanone end group were easily prepared via three synthetic steps. These acceptors exhibited broad absorption in the range of ...Two simple electron acceptors based on unfused bithiophene core and 1,1-dicyanomethylene-3-indanone end group were easily prepared via three synthetic steps. These acceptors exhibited broad absorption in the range of 300 nm to 800 nm, aligned energy levels and high crystallinity. When combined with a wide band gap donor polymer in non-fullerene solar cells, an initial power conversion efficiency of 2.4% was achieved. The relatively low efficiencies were due to the large phase separation in blended thin films, which is originated from their high aggregation tendency in thin films. Our results suggest that these electron acceptors with unfused core are promising candidates for commercial application of solar cells due to the low cost starting materials and facile synthesis.展开更多
We present here a series of perylene diimide(PDI)based isomeric conjugated polymers for the application as efficient electron acceptors in all-polymer solar cells(all-PSCs).By copolymerizing PDI monomers with 1,4-diet...We present here a series of perylene diimide(PDI)based isomeric conjugated polymers for the application as efficient electron acceptors in all-polymer solar cells(all-PSCs).By copolymerizing PDI monomers with 1,4-diethynylbenzene(para-linkage)and 1,3-diethynylbenzene(meta-linkage),isomeric PDI based conjugated polymers with parallel and non-parallel PDI units inside backbones were obtained.It was found that para-linked conjugated polymer(PA)showed better solubility,strongerπ-πstacking,more favorable blend morphology,and better photovoltaic performance than those of meta-linked conjugated polymers(PM)did.Device based on PTB7-Th:PA(PTB7-Th:poly{4,8-bis[5-(2-ethylhexyl)-thiophen-2-yl]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl-alt-3-fluoro-2-[(2-ethylhexyl)-carbonyl]thieno[3,4-b]thiophene-4,6-diyl})showed significantly enhanced photovoltaic performance than that of PTB7-Th:MA(3.29%versus 0.92%).Moreover,the photovoltaic performance of these polymeric acceptors could be further improved via a terpolymeric strategy.By copolymerizing a small amount of meta-linkages into PA,the optimized terpolymeric acceptors enabled to enhance photovoltaic performance with improved the short-circuit current density(Jsc)and fill factor(FF),resulting in an improved power conversion efficiency(PCE)of 4.03%.展开更多
Polymer electron acceptors for all-polymer solar cells （all-PSCs） are usually conjugated copolymers, which contain alternating electron-rich units and electron-deficient units. In this manuscript, we report a conjug...Polymer electron acceptors for all-polymer solar cells （all-PSCs） are usually conjugated copolymers, which contain alternating electron-rich units and electron-deficient units. In this manuscript, we report a conjugated homopolymer （P-BNBP） based on an electron-deficient unit of double B,--N bridged bipyridine, which can be used as electron acceptor for all-polymer solar cells. P-BNBP shows low-lying LUMO energy level of -3.59eV, high absorption coefficient of 1.6 ×10^5Lmo1^-1 cm^-1 at 626nm and moderate electron mobility of 4.37 ×10^-6cm^2V^-1s^-1. AII-PSC devices exhibit power conversion efficiencies of 2.44%-3.04%. These results demonstrate that conjugated homopolymers are promising as electron acceptor materials for alI-PSCs.展开更多
Nonfused ring electron acceptors(NFREAs)have attracted much attention due to their concise synthetic routes and low cost.However,developing high-performance NFREAs with simple structure remains a great challenge.In th...Nonfused ring electron acceptors(NFREAs)have attracted much attention due to their concise synthetic routes and low cost.However,developing high-performance NFREAs with simple structure remains a great challenge.In this work,a simple building block(POBT)with noncovalently conformational locks(No CLs)was designed and synthesized.Single-crystal X-ray study indicated the presence of S…O NOCLs in POBT,thus enabling it to possess a coplanar conformation comparable to that of fused-ring CPT.Two novel NFREAs based on CPT and POBT were developed,namely TT-CPT and TT-POBT,respectively.Besides,TT-POBT possessed a smaller Stokes shift and a reduced reorganization energy compared with TT-CPT,indicating the introduction of S…O No CLs can enhance the molecular rigidity even if simplifying the molecular structure.As a result,the TT-POBT-based PSC device afforded an impressive power conversion efficiency of 11.15%,much higher than that of TT-CPT counterpart(7.03%),mainly resulting from the tighterπ-πstacking,improved and balanced charge transport,and more favorable film morphology.This work demonstrates the potential of the simple building block POBT with No CLs towards constructing low-cost and highperformance NFREAs.展开更多
The effects of two different external carbon sources （acetate and ethanol） and electron acceptors （dissolved oxygen, nitrate, and nitrite） were investigated under aerobic and anoxic conditions with non-acclimated ...The effects of two different external carbon sources （acetate and ethanol） and electron acceptors （dissolved oxygen, nitrate, and nitrite） were investigated under aerobic and anoxic conditions with non-acclimated process bi- omass from a full-scale biological nutrient removal-activated sludge system. When acetate was added as an external carbon source, phosphate release was observed even in the presence of electron acceptors. The release rates were 1.7, 7.8, and 3.5 mg P/（g MLVSS.h） （MLVSS： mixed liquor volatile suspended solids）, respectively, for dissolved oxygen, nitrate, and nitrite. In the case of ethanol, no phosphate release was observed in the presence of electron acceptors. Results of the experiments with nitrite showed that approximately 25 mg NO2-N/L of nitrite inhibited anoxic phosphorus uptake regardless of the concentration of the tested external carbon sources. Furthermore, higher deni- trification rates were obtained with acetate （1.4 and 0.8 mg N/（g MLVSS.h）） compared to ethanol （1.1 and 0.7 mg N/ （g MLVSS.h）） for both anoxic electron acceptors （nitrate and nitrite）.展开更多
The effect of the electron acceptors H2O2 and O2 on the type of generated reactive oxygen species（ROS）,and glycerol conversion and product distribution in the TiO2-catalyzed photocatalytic oxidation of glycerol was ...The effect of the electron acceptors H2O2 and O2 on the type of generated reactive oxygen species（ROS）,and glycerol conversion and product distribution in the TiO2-catalyzed photocatalytic oxidation of glycerol was studied at ambient conditions.In the absence of an electron acceptor,only HO^·radicals were generated by irradiated UV light and TiO2.However,in the presence of the two electron acceptors,both HO^· radical and ^1O2 were produced by irradiated UV light and TiO2 in different concentrations that depended on the concentration of the electron acceptor.The use of H2O2 as an electron acceptor enhanced glycerol conversion more than O2.The type of generated value-added compounds depended on the concentration of the generated ROS.展开更多
基金This work was financially supported by the National Natural Science Foundation of China(Nos.U21A20101 and 22105208)China Postdoctoral Science Foundation(No.2021M703263).
文摘We synthesize and compare four near-infrared absorbing fused-ring electron acceptors named as nTTIC(n=2,3,4,and 5),based on different number of thieno[3,2-b]thiophene(TT)unit as the electron-donating core.With increasing the TT unit,absorption spectrum of the TTIC series red shifts,and the highest occupied molecular orbital(HOMO)upshifts notably.It is worth noting that 4TTIC and 5TTIC exhibit absorption edges approaching 1100 nm,which is the photoresponse limit of solar cells based on crystal silicon.When the TTIC series acceptors are blended with polymer donor PM6,the binary-blend organic solar cells based on 3TTIC show the best power conversion efficiency(PCE)of 13.1%.In contrast,2TTIC-based devices exhibit relatively lower PCE of 8.32%,mainly caused by the larger energy loss and blue-shifted absorption.Due to insufficient driving force of charge separation caused by very high HOMO,4TTIC and 5TTIC show poor PCEs lower than 3%.
基金the financial support fromtheNSFC(21975055,U2001222,52103352,52120105006,and 51925306)National Key R&D Program of China(2018FYA 0305800)+2 种基金Key Research Program of Chinese Academy of Sciences(XDPB08-2)the Youth Innovation Promotion Association of Chinese Academy of Sciences(2022165)the Fundamental Research Funds for the Central Universities.DFT results described in this article were obtained from the National Supercomputing Centre in Shenzhen(Shenzhen Cloud Computing Centre).
文摘By employing the asymmetric end-group engineering,an asymmetric nonfused-ring electron acceptor(NFREA)was designed and synthesized.Compared with the symmetric analogs(NoCA-17 and NoCA-18),NoCA-19 possesses broader light absorption range,more coplanarπ-conjugated backbone,and appropriate crystallinity according to the experimental and theoretical results.The organic solar cells based on J52:NoCA-19 exhibited a power conversion efficiency as high as 12.26%,which is much higher than those of J52:NoCA-17(9.50%)and J52:NoCA-18(11.77%),mainly due to more efficient exciton dissociation,better and balanced charge mobility,suppressed recombination loss,shorter charge extraction time,longer charge carrier lifetimes,and more favorable blend film morphology.These findings demonstrate the great potential of asymmetric end-group engineering in exploring low-cost and high-performance NFREAs.
基金This work is supported by the National Natural Science Foundation of China(U21A20101).
文摘Fullerene derivatives are classic electron acceptor materials for organic solar cells (Oscs) but possess some intrinsic drawbacks such as weak visiblelightabsorption,limitedoptoelectronic property tunability,dificult purification and photochemical/morphological instability.Fullereneacceptors area bottleneck restricting further development of this field. Ourgroup pioneered the exploration of novel nonfulerene acceptors in China in 2006,andinitiated the research of two representative acceptor systems, rylene dimide polymer and fused-ring electron acceptor (FREA).FREA breaks the theoreticalefficiencylimit of fullerene-based OsCs (-13%) and promotes the whole field to an unprecedented prosperity with efficiency of 20%, heraldinga nonfullerene era for OsCs.In this review, we revisit 15-year nonfullerene exploration journey,summarize the design principles,molecular engineeringstrategies, physical mechanisms and device applications of these two nonfullerene acceptor systems, and propose some possible researchtopics in the nearfuture.
文摘We propose a strategy to improve performance of unidirectionally extended fused-ring electron acceptors by using pyrrolo[3,2-b]pyrrole to replace pyrrole ring, and design two asymmetric nonfullerene acceptors 1PIC and 2PIC. Replacing pyrrole in 1PIC with pyrrolo[3,2-b]pyrrole remarkably red-shifts absorption peak by 109 nm, elevates the HOMO and LUMO energy levels, and improves electron mobility. The photovoltaic devices based on blend of PM6 donor and 2PIC acceptor exhibit power conversion efficiency as high as 12.6%, which is much higher than that of PM6:1PIC (3.53%), due to more efficient exciton generation and dissociation, faster and more balanced carrier transport and less charge recombination.
基金Natural Science Foundation for Distinguished Young Scholars of Guangdong Province,Grant/Award Number:2021B1515020027Science and Technology Projects in Guangzhou,Grant/Award Number:202201000002+4 种基金Shenzhen Science and Technology Innovation Commission,Grant/Award Numbers:JCYJ202103243104813035,JCYJ20180504165709042GuangDong Basic and Applied Basic Research Foundation,Grant/Award Number:2021A1515110892China Postdoctoral Science Foundation,Grant/Award Number:2021M700062Open Fund of the State Key Laboratory of Luminescent Materials and Devices,Grant/Award Number:2022-skllmd-17X.G.,H.S.,and Y.J.are thankful for the financial support from the Songshan Lake Materials Laboratory,Grant/Award Number:2021SLABFK03。
文摘The power conversion efficiencies(PCEs)of organic solar cells(OSCs)have improved considerably in recent years with the development of fused-ring electron acceptors(FREAs).Currently,FREAs-based OSCs have achieved high PCEs of over 19%in single-junction OSCs.Whereas the relatively high synthetic complexity and the low yield of FREAs typically result in high production costs,hindering the commercial application of OSCs.In contrast,noncovalently fused-ring electron acceptors(NFREAs)can compensate for the shortcomings of FREAs and facilitate large-scale industrial production by virtue of the simple structure,facile synthesis,high yield,low cost,and reasonable efficiency.At present,OSCs based on NFREAs have exceeded the PCEs of 15%and are expected to reach comparable efficiency as FREAs-based OSCs.Here,recent advances in NFREAs in this review provide insight into improving the performance of OSCs.In particular,this paper focuses on the effect of the chemical structures of NFREAs on the molecule conformation,aggregation,and packing mode.Various molecular design strategies,such as core,side-chain,and terminal group engineering,are presented.In addition,some novel polymer acceptors based on NFREAs for all-polymer OSCs are also introduced.In the end,the paper provides an outlook on developing efficient,stable,and low-cost NFREAs for achieving commercial applications.
基金NSFC,Grant/Award Numbers:52120105006,52103352,51925306National Key R&D Program of China,Grant/Award Number:2018FYA 0305800Youth Innovation Promotion Association of Chinese Academy of Sciences,Grant/Award Number:2022165。
文摘Organic solar cells(OSCs)have attracted extensive attention from both academia and industry in recent years due to their remarkable improvement in power conversion efficiency(PCE).However,the Golden Triangle(the balance of efficiency-stability-cost)required for large-scale industrialization of OSCs still remains a great challenge.Here,a new nonfused-ring electron acceptor(NFREA)BF and its polymerized counterpart PBF were designed and synthesized,and their photovoltaic performance,storage stability and material cost were systematically investigated.When blended with a widely-used polymer donor PBDB-T,the PBFbased all-polymer solar cell(all-PSC)displayed a record high PCE of 12.61%for polymerized NFREAs(PNFREAs)with an excellent stability(95.2%of initial PCE after 800 h storage),superior to the BF counterpart.Impressively,PBF-based allPSC possesses the highest industrial figure-of-merit(i-FOM)value of 0.309 based on an efficiency-stability-cost evaluation,in comparison to several representative OSC systems(such as PM6:Y6 and PBDB-T:PZ1).This work provides an insight into the balance of efficiency,stability,and cost,and also indicates that the PNFREAs are promising materials toward the commercial application of OSCs.
基金National Science Foundation of China,Grant/Award Numbers:51761165023,21734001。
文摘A new fused-ring electron acceptor FNIC3 with dynamics controlled aggregation behavior was synthesized.FNIC3 shows strong absorption in 600–900 nm,HOMO/LUMO energy levels of−5.59/−4.04 eV,and electron mobility of 1.2×10^(−3) cm^(2) V^(−1) s^(−1).The aggregation of FNIC3 shows strong dependency on film formation time.Prolongation of film formation time promotes the crystallization of FNIC3,leading to improved crystallinity and enlarged aggregate sizes.Aggregation of FNIC3 significantly influences the photovoltaic device parameters.Appropriate aggregation red-shifts the absorption and improves the mobilities of the blend,which contributes to high photocurrent and fill factor thus high power conversion efficiency(PCE).Overaggregation leads to increased nonradiative energy loss and insufficient charge generation,resulting in decreased open-circuit voltage and short-circuit current density.The blends based on PM6:FNIC3 fabricated under proper film formation time exhibit a PCE of 12.3%,higher than those fabricated under short and long film formation time(10.0–10.5%).
基金the National Natural Science Foundation of China((52120105006,52103352,and 51925306)National Key R&D Program of China(2018FYA 0305800)+3 种基金Key Research Program of Chinese Academy of Sciences(XDPB08-2)the Strategic Priority Research Program of Chinese Academy of Sciences(XDB28000000)the Youth Innovation Promotion Association of Chinese Academy of Sciences(2022165)the Fundamental Research Funds for the Central Universities.DFT results described in this report were obtained from the National Supercomputing Center in Shenzhen(Shenzhen CloudComputing Center).
文摘Comprehensive Summary By employing thiazole and 4-chlorothiazole as the A′units,two A-D-A′-D-A type nonfused-ring electron acceptors(NFREAs)Tz-H and Tz-Cl were designed and synthesized.Replacing thiazole in Tz-H with 4-chlorothiazole can not only remarkably shorten the synthetic route through C—H direct arylation but also enhance molecular planarity with the simultaneous incorporation of S…N and S…Cl noncovalently conformational locks(NoCLs).The photovoltaic devices based on PM6:Tz-Cl exhibited a power conversion efficiency as high as 11.10%,much higher than that of PM6:Tz-H(6.41%),mainly due to more efficient exciton dissociation,better and more balanced carrier mobility,less charge recombination,and more favorable morphology.These findings demonstrate the great potential of NoCLs in achieving low-cost and high-performance NFREAs.
基金The authors gratefully acknowledge the financial support from the Beijing National Laboratory for Molecular Sciences and the National Natural Science Foundation of China(61935016 and 21771008)X.Z.thanks National Key Research and Development Program of China(2020YFB1506400).
文摘The performance of tin-based perovskite solar cells has been substantially hampered by voltage loss caused by energy level mismatch,charge recombination,energetic disorder,and other issues.Here,a fused-ring electron acceptor based on indacenodithiophene(IDIC)was for the first time introduced as a transition layer between a tin-based perovskite layer and a C 60 electron transport layer,leading to better matched energy levels in the device.In addition,coordination interactions between IDIC and perovskite improved the latter's crystallinity.The introduction of IDIC raised the power conversion efficiency from 8.98%to 11.5%and improved the device's stability.The decomposition mechanism of tin-based perovskite was also revealed by detecting the optical properties of perovskite microdomains through innovative integration of confocal laser scanning microscopy and photoluminescence spectroscopy.
基金financially supported by the Guangdong Major Project of Basic and Applied Basic Research(No.2023B0303000002)the Shenzhen Key Laboratory of Advanced Energy Storage(ZDSYS20220401141000001)the High level of special funds(G03034K001)。
文摘High-voltage lithium(Li)metal batteries(LMBs)face substantial challenges,including Li dendrite growth and instability in high-voltage cathodes such as LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)(NCM811),which impede their practical applications and long-term stability.To address these challenges,tris(pentafluorophenyl)borane additive as an electron acceptor is introduced into an ethyl methyl carbonate/fluoroethylene carbonate-based electrolyte.This approach effectively engineers robust dual interfaces on the Li metal anode and the NCM811 cathode,thereby mitigating dendritic growth of Li and enhancing the stability of the cathode.This additive-driven strategy enables LMBs to operate at ultra-high voltages up to 4.7 V.Consequently,Li||Cu cells achieve a coulombic efficiency of 98.96%,and Li||Li symmetric cells extend their cycle life to an impressive 4000 h.Li||NCM811 full cells maintain a high capacity retention of 87.8%after 100 cycles at 4.7 V.Additionally,Li||LNMO full cells exhibit exceptional rate capability,delivering 132.2 mAh g^(-1)at 10 C and retaining 95.0%capacity after 250 cycles at 1 C and 5 V.As a result,NCM811||graphite pouch cells maintain a 93.4%capacity retention after 1100 cycles at 1 C.These findings underscore the efficacy of additive engineering in addressing Li dendrite formation and instability of cathode under high voltage,thereby paving the road for durable,high-performance LMBs.
基金funded by 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Developing narrow-bandgap organic semiconductors is important to facilitate the advancement of organic photovoltaics(OPVs). Herein, two near-infrared non-fused ring acceptors(NIR NFRAs), PTBFTT-F and PTBFTT-Cl have been developed with A-π_A-π_D-D-π_D-π_A-A non-fused structures. It is revealed that the introduction of electron deficient π-bridge(π_A) and multiple intramolecular noncovalent interactions effectively retained the structural planarity and intramolecular charge transfer of NFRAs, extending strong NIR photon absorption up to 950 nm. Further, the chlorinated acceptor, with the enlarged π-surface compared to the fluorinated counterpart, promoted not only molecular stacking in solid, but also the desirable photochemical stability in ambient, which are helpful to thereby improve the exciton and charge dynamics for the corresponding OPVs. Overall, this work provides valuable insights into the design of NIR organic semiconductors.
基金supported by the Beijing Natural Science Foundation of China(Z230019,2212005)the National Natural Science Foundation of China(NSFC 22173062,21833005,22090022 and 22275125).
文摘Low-cost photovoltaic materials are essential for realizing large-scale commercial applications of organic solar cells(OSCs).However,highly efficient OSCs based on low-cost photovoltaic materials are scarce due to a deficiency in understanding the structure-property relationship.Herein,we investigated two low-cost terthiophene-based electron acceptors,namely,3TC8 and 3TEH,with 3,4-bis(octan-3-yloxy)thiophene,differing only in the alkylated thiophene-bridges.Both acceptors exhibit low optical gaps(∼1.43 eV)and possess deep highest occupied molecular orbital(HOMO)levels(∼−5.8 eV).Notably,the single-crystal structure of 3TEH demonstrates highly planar conjugated backbone and strongπ-πstacking between intermolecular terminal groups,attributed to the presence of the bulky alkylated noncovalently conformational locks.Upon utilizing both acceptors to fabricate OSCs,the 3TC8-based device exhibited a power conversion efficiency(PCE)of 11.1%,while the 3TEH-based OSC demonstrated an excellent PCE of 14.4%.This PCE is the highest among OSCs based on terthiophene-containing electron acceptors.These results offer a new strategy for designing low-cost electron acceptors for highly efficient OSCs.
基金Project(2022LSL050102)supported by the Laoshan Laboratory,China。
文摘Sulfate and nitrate reducing bacteria are important culprits for microbiologically influenced corrosion(MIC)using sulfate and nitrate as electron acceptors,respectively.Sulfate and nitrate hold different standard electrode potentials,which may lead to differences in corrosion,but their effects on corrosion by the same bacteria have not been reported.The corrosion of Q235 steel affected by Pseudodesulfovibrio cashew(P.cashew)in the sulfate and nitrate media under carbon starvation was studied.It was found that sulfate and nitrate did not lead to differences in corrosion under abiotic conditions.However,P.cashew promoted corrosion in both cases,and the consumption of H_(2)was the main mechanism for MIC.In addition,corrosion was more severe in the sulfate media.The higher corrosivity of P.cashew with sulfate as the electron acceptor is closely related to the higher number of sessile cells in the biofilm,higher bacterial motility,more hydrogen production pathways,and the increased gene expression of enzymes related to energy synthesis.
基金supported by the National Natural Science Foundation of China(No.51973020)Beijing Natural Science Foundation(No.2232052)。
文摘A binary-mixed electron transport layer(ETL)has been reported for constructing solution-processable near-infrared organic light-emitting diodes(NIR OLEDs).Relative to the single-component ETL,the binarymixed ETL composed of PDINN:TPBi can enhance the carrier transport capacity,reduce device impedance,and weaken fiuorescence quenching of the emitting layer.By carefully selecting an appropriate luminescent material Y5(a nonfullerene electron acceptor in organic solar cells)and precisely fine-tuning the molecular aggregation in active layer using a mixed solvent,the morphology is optimized and luminescence performance is enhanced,resulting in efficient NIR OLEDs with an emission peak at 890 nm.The experiment showcases a Y5-based near-infrared OLED with a maximum radiance of 34.9 W sr^(-1)m^(-2)and a maximum external quantum efficiency of 0.50%,which is among the highest values reported for nondoped fiuorescent NIR OLEDs with an emission peak over 850 nm.
基金supported by MOST (No. 2017YFA0204702)National Natural Science Foundation of China (Nos. 51773207, 21574138, 51603209, 91633301)supported by the Strategic Priority Research Program (No. XDB12030200) of the Chinese Academy of Sciences and the Recruitment Program of Global Youth Experts of China
文摘Two simple electron acceptors based on unfused bithiophene core and 1,1-dicyanomethylene-3-indanone end group were easily prepared via three synthetic steps. These acceptors exhibited broad absorption in the range of 300 nm to 800 nm, aligned energy levels and high crystallinity. When combined with a wide band gap donor polymer in non-fullerene solar cells, an initial power conversion efficiency of 2.4% was achieved. The relatively low efficiencies were due to the large phase separation in blended thin films, which is originated from their high aggregation tendency in thin films. Our results suggest that these electron acceptors with unfused core are promising candidates for commercial application of solar cells due to the low cost starting materials and facile synthesis.
基金financially supported by the Ministry of Science and Technology of China (No. 2014CB643501)the National Natural Science Foundation of China (Nos. 21634004 and 51403070)+1 种基金the Foundation of Guangzhou Science and Technology Project (No. 201707020019)Zhi-Cheng Hu thanks the financial support from China Postdoctoral Science Foundation (No. 2017M622684)
文摘We present here a series of perylene diimide(PDI)based isomeric conjugated polymers for the application as efficient electron acceptors in all-polymer solar cells(all-PSCs).By copolymerizing PDI monomers with 1,4-diethynylbenzene(para-linkage)and 1,3-diethynylbenzene(meta-linkage),isomeric PDI based conjugated polymers with parallel and non-parallel PDI units inside backbones were obtained.It was found that para-linked conjugated polymer(PA)showed better solubility,strongerπ-πstacking,more favorable blend morphology,and better photovoltaic performance than those of meta-linked conjugated polymers(PM)did.Device based on PTB7-Th:PA(PTB7-Th:poly{4,8-bis[5-(2-ethylhexyl)-thiophen-2-yl]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl-alt-3-fluoro-2-[(2-ethylhexyl)-carbonyl]thieno[3,4-b]thiophene-4,6-diyl})showed significantly enhanced photovoltaic performance than that of PTB7-Th:MA(3.29%versus 0.92%).Moreover,the photovoltaic performance of these polymeric acceptors could be further improved via a terpolymeric strategy.By copolymerizing a small amount of meta-linkages into PA,the optimized terpolymeric acceptors enabled to enhance photovoltaic performance with improved the short-circuit current density(Jsc)and fill factor(FF),resulting in an improved power conversion efficiency(PCE)of 4.03%.
基金supported by the National Natural Science Foundation of China (Nos.21625403,21574129)Strategic Priority Research Program of Chinese Academy of Sciences (No.XDB12010200)+2 种基金Jilin Scientific and Technological Development Program (No.20170519003JH)Youth Innovation Promotion Association of Chinese Academy of Sciences (No.2017265)Open Project (No.sklssm201803) of the State Key Laboratory of Supramolecular Structure and Materials in Jilin University of China
文摘Polymer electron acceptors for all-polymer solar cells （all-PSCs） are usually conjugated copolymers, which contain alternating electron-rich units and electron-deficient units. In this manuscript, we report a conjugated homopolymer （P-BNBP） based on an electron-deficient unit of double B,--N bridged bipyridine, which can be used as electron acceptor for all-polymer solar cells. P-BNBP shows low-lying LUMO energy level of -3.59eV, high absorption coefficient of 1.6 ×10^5Lmo1^-1 cm^-1 at 626nm and moderate electron mobility of 4.37 ×10^-6cm^2V^-1s^-1. AII-PSC devices exhibit power conversion efficiencies of 2.44%-3.04%. These results demonstrate that conjugated homopolymers are promising as electron acceptor materials for alI-PSCs.
基金the National Natural Science Foundation of China(Nos.52103352,51925306 and 52120105006)National Key R&D Program of China(No.2018FYA 0305800)+3 种基金Key Research Program of Chinese Academy of Sciences(No.XDPB08-2)the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB28000000)the Youth Innovation Promotion Association of Chinese Academy of Sciences(No.2022165)the Fundamental Research Funds for the Central Universities.
文摘Nonfused ring electron acceptors(NFREAs)have attracted much attention due to their concise synthetic routes and low cost.However,developing high-performance NFREAs with simple structure remains a great challenge.In this work,a simple building block(POBT)with noncovalently conformational locks(No CLs)was designed and synthesized.Single-crystal X-ray study indicated the presence of S…O NOCLs in POBT,thus enabling it to possess a coplanar conformation comparable to that of fused-ring CPT.Two novel NFREAs based on CPT and POBT were developed,namely TT-CPT and TT-POBT,respectively.Besides,TT-POBT possessed a smaller Stokes shift and a reduced reorganization energy compared with TT-CPT,indicating the introduction of S…O No CLs can enhance the molecular rigidity even if simplifying the molecular structure.As a result,the TT-POBT-based PSC device afforded an impressive power conversion efficiency of 11.15%,much higher than that of TT-CPT counterpart(7.03%),mainly resulting from the tighterπ-πstacking,improved and balanced charge transport,and more favorable film morphology.This work demonstrates the potential of the simple building block POBT with No CLs towards constructing low-cost and highperformance NFREAs.
基金Project supported by the European Regional Development Fund within the Framework of the Innovative Economy Operational Program 2007-2013(No.UDA-POIG.01.03.01-22-140/09-04)the CARbon BALAncing for Nutrient Control in Wastewater Treatment(CARBALA)(No.PIRSES-GA-2011-295176)the National Water Pollution Control and Management of Science and Technology in China(No.2015ZX07218001)
文摘The effects of two different external carbon sources （acetate and ethanol） and electron acceptors （dissolved oxygen, nitrate, and nitrite） were investigated under aerobic and anoxic conditions with non-acclimated process bi- omass from a full-scale biological nutrient removal-activated sludge system. When acetate was added as an external carbon source, phosphate release was observed even in the presence of electron acceptors. The release rates were 1.7, 7.8, and 3.5 mg P/（g MLVSS.h） （MLVSS： mixed liquor volatile suspended solids）, respectively, for dissolved oxygen, nitrate, and nitrite. In the case of ethanol, no phosphate release was observed in the presence of electron acceptors. Results of the experiments with nitrite showed that approximately 25 mg NO2-N/L of nitrite inhibited anoxic phosphorus uptake regardless of the concentration of the tested external carbon sources. Furthermore, higher deni- trification rates were obtained with acetate （1.4 and 0.8 mg N/（g MLVSS.h）） compared to ethanol （1.1 and 0.7 mg N/ （g MLVSS.h）） for both anoxic electron acceptors （nitrate and nitrite）.
基金Chulalongkorn University Dutsadi Phiphat Scholarshipthe Ratchadapisek Sompoch Endowment Fund(Sci-Super Ⅱ GF_58_08_23_01)the Thailand Research Fund(IRG5780001) for financial support
文摘The effect of the electron acceptors H2O2 and O2 on the type of generated reactive oxygen species（ROS）,and glycerol conversion and product distribution in the TiO2-catalyzed photocatalytic oxidation of glycerol was studied at ambient conditions.In the absence of an electron acceptor,only HO^·radicals were generated by irradiated UV light and TiO2.However,in the presence of the two electron acceptors,both HO^· radical and ^1O2 were produced by irradiated UV light and TiO2 in different concentrations that depended on the concentration of the electron acceptor.The use of H2O2 as an electron acceptor enhanced glycerol conversion more than O2.The type of generated value-added compounds depended on the concentration of the generated ROS.
