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1.
Artigo em Inglês | MEDLINE | ID: mdl-33538571

RESUMO

To face the challenge of all-climate application, organic rechargeable batteries must hold the capability of efficiently operating both at high temperatures (>50 °C) and low temperatures (-20 °C). However, the low electronic conductivity and high solubility of organic molecules significantly impede the development in electrochemical energy storage. This issue can be effectively diminished using functionalized porphyrin complex-based organic cathodes by the in-situ electropolymerization of electrodes at elevating temperatures during electrochemical cycling. [5,15-bis(ethynyl)-10,20-diphenylporphinato]copper(II) (CuDEPP)- and 5,15-bis(ethynyl)-10,20-diphenylporphinato (DEPP)-based cathodes are proposed as models, and it is proved that a largely improved electrochemical performance is observed in both cathodes at a high operating temperature. Reversible capacities of 249 and 105 mA h g-1 are obtained for the CuDEPP and DEPP cathodes after 1000 cycles at 50 °C, respectively. The result indicates that the temperature-induced in situ electropolymerization strategy responds to the enhanced electrochemical performance. This study would open new opportunities for developing highly stable organic cathodes for electrochemical energy storage even at high temperatures.

2.
Nat Commun ; 11(1): 6005, 2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33243982

RESUMO

In non-fullerene organic solar cells, the long-range structure ordering induced by end-group π-π stacking of fused-ring non-fullerene acceptors is considered as the critical factor in realizing efficient charge transport and high power conversion efficiency. Here, we demonstrate that side-chain engineering of non-fullerene acceptors could drive the fused-ring backbone assembly from a π-π stacking mode to an intermixed packing mode, and to a non-stacking mode to refine its solid-state properties. Different from the above-mentioned understanding, we find that close atom contacts in a non-stacking mode can form efficient charge transport pathway through close side atom interactions. The intermixed solid-state packing motif in active layers could enable organic solar cells with superior efficiency and reduced non-radiative recombination loss compared with devices based on molecules with the classic end-group π-π stacking mode. Our observations open a new avenue in material design that endows better photovoltaic performance.

3.
ACS Appl Mater Interfaces ; 12(40): 44679-44688, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-32907330

RESUMO

Three cationic polyelectrolytes polyethyleneimine ethoxylate (PEIE)-1,4-butanediol dimethylsulfonate (MSB), PEIE-1,4-butanediol diethylsulfonate (ESB), and PEIE-1,4-butanediol dibenzylsulfonate (BSB), containing methylsulfonate, ethylsulfonate, and benzylsulfonate, respectively, were prepared for cathode interface layers (CILs) via a one-step reaction with 1,4-butanediol dialkylsulfonate and PEIE as the reactants. The results indicate that PEIE-MSB and PEIE-ESB with smaller counterions possess more efficient electron extraction, higher electron mobilities, and better photovoltaic performance than PEIE-BSB with larger counterions. The PTB7-Th:PC71BM-based single junction bulk heterojunction polymer solar cells (PSCs) with PEIE-ESB as the CIL showed power conversion efficiencies (PCEs) of 10.44 and 9.23% under the thickness conditions of 8 and 30 nm, respectively. The PM6:Y6-based PSCs displayed a high PCE of 15.69%. The study provides not only new high-performance CILs but also a new strategy to construct light-soaking-free PSCs via tuning alkylsulfonate counterions.

4.
ACS Appl Mater Interfaces ; 12(39): 43984-43991, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-32885945

RESUMO

The energy offset, considered as the driving force for charge transfer between organic molecules, has significant effects on both charge separation and charge recombination in organic solar cells. Herein, we designed material systems with gradually shifting energy offsets, including both positive and negative values. Time-resolved spectroscopy was used to monitor the charge dynamics within the bulk heterojunction. It is striking to find that there is still charge transfer and charge generation when the energy offset reached -0.10 eV (ultraviolet photoelectron spectroscopy data). This work not only indicates the feasibility of the free carrier generation and the following charge separation under the condition of a negative offset but also elucidates the relationship between the charge transfer and the energy offset in the case of polymer chlorination.

5.
Nat Commun ; 11(1): 2855, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32503994

RESUMO

Morphology control in laboratory and industry setting remains as a major challenge for organic solar cells (OSCs) due to the difference in film-drying kinetics between spin coating and the printing process. A two-step sequential deposition method is developed to control the active layer morphology. A conjugated polymer that self-assembles into a well-defined fibril structure is used as the first layer, and then a non-fullerene acceptor is introduced into the fibril mesh as the second layer to form an optimal morphology. A benefit of the combined fibril network morphology and non-fullerene acceptor properties was that a high efficiency of 16.5% (certified as 16.1%) was achieved. The preformed fibril network layer and the sequentially deposited non-fullerene acceptor form a robust morphology that is insensitive to the polymer batches, solving a notorious issue in OSCs. Such progress demonstrates that the utilization of polymer fibril networks in a sequential deposition process is a promising approach towards the fabrication of high-efficiency OSCs.

6.
Chem Commun (Camb) ; 56(40): 5437-5440, 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32292939

RESUMO

A highly conjugated polymeric porphyrin with an ethynyl group is proposed as a new cathode for lithium organic batteries. The electrochemical performance is significantly improved after a simple coupled polymerization, resulting in excellent cycling stability with a capacity retention of 99.2% for 2000 cycles.

7.
ChemSusChem ; 13(9): 2286-2294, 2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-32187437

RESUMO

Rechargeable potassium-ion batteries (KIBs) are promising alternatives to lithium-ion batteries for large-scale electrochemical energy-storage applications because of the abundance and low cost of potassium. However, the development of KIBs is hampered by the lack of stable and high-capacity cathode materials. Herein, a functionalized porphyrin complex, [5,15-bis(ethynyl)-10,20-diphenylporphinato]copper(II) (CuDEPP), was proposed as a new cathode for rechargeable potassium batteries. Spectroscopy and molecular simulation studies were used to show that both PF6 - and K+ interact with the porphyrin macrocycle to allow a four-electron transfer. In addition, the electrochemical polymerization of the ethynyl functional groups in CuDEPP resulted in the self-stabilization of the cathode, which was highly stable during cycling. This unique charge storage mechanism enabled CuDEPP to provide a capacity of 181 mAh g-1 with an average potential of 2.8 V (vs. K+ /K). These findings could open a pathway towards the design of new stable organic electrodes for KIBs.

8.
ACS Appl Mater Interfaces ; 11(51): 48134-48146, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31823611

RESUMO

In this contribution, a series of A-π-D-π-A small molecules (SMs), IPY-T-IC, IPY-T-ICCl, and IPY-T-ICF, containing the central donor unit (D) of 6,12-dihydro-diindolo[1,2-b:10,20-e]pyrazine (IPY), the π-conjugated bridge of thiophene, and the end-accepting group (A) of 3-(dic yanomethylidene)indol-1-one, 5,6-dichloro-3-(dicyanomethylidene)indol-1-one, or 5,6-difluoro-3-(dicyanomethylene)indol-1-one, were developed, characterized, and employed as the acceptor materials for polymer solar cells (PSCs). Influences of the different end-accepting groups on thermal properties, spectral absorption, energy levels, photovoltaic performance, and film morphology of these small-molecule acceptors (SMAs) were investigated in detail. These SMAs exhibit an excellent thermal stability and strong crystallization. The absorption spectra of these SMs mainly locate the wavelength between 400 and 700 nm, associated with the optical band gaps in the range of 1.75-1.90 eV. Compared with nonhalogenated IPY-T-IC, the halogenated SMAs IPY-T-ICCl and IPY-T-ICF present better absorption abilities, wider absorption region, and downshifted highest occupied molecular orbital (HOMO)/lowest unoccupied molecular orbital (LUMO) levels. With regard to the complementary spectral absorption and matched HOMO/LUMO levels, PTB7-Th as a low-band gap polymer was chosen to be an electron donor to pair with these SMAs for fabricating bulk-heterojuntion PSCs. Under optimized conditions, among these SMAs, the PTB7-Th:IPY-T-IC-based PSC processed from a halogenated solvent system (chlorobenzene + 1-chloronaphthalene) delivers the best power conversion efficiency (PCE) of 7.32%, mainly because of more complementary spectral absorption, upper-lying LUMO level, higher and balanced carrier mobility, more efficiently suppressed trap-assisted recombination, better charge collection property, and blend morphology. Encouragingly, an improved PCE of up to 7.68% is achieved when the IPY-T-IC-based solar cell was processed from a nonhalogenated solvent system (o-xylene + 2-methylnaphthalene). In view of the large band gap of these IPY-based SMAs, the PCE of over 7.5% is notable and attractive for the related community. Our study argues that the IPY moiety is a potential electron-donating building moiety to develop medium-band-gap high-performance A-π-D-π-A SMAs for nonhalogenated-solvent-processed photovoltaic devices.

10.
Adv Mater ; 29(4)2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27922201

RESUMO

Rational heteroatom engineering is applied to develop high-performance electron-transporting naphthalenediimide copolymers. Top-gate field-effect transistors fabricated from selenophene-containing polymers achieve an ultrahigh electron mobility of 8.5 cm2 V-1 s-1 and excellent air-stability. The results demonstrate that the incorporation of selenophene heterocycles into the polymers can improve the film-forming ability, intermolecular interaction, and carrier transport significantly.

11.
ACS Appl Mater Interfaces ; 8(48): 33051-33059, 2016 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-27934139

RESUMO

Five-membered 1,3,4-oxadiazole (OZ) and 1,3,4-thiadiazole (TZ) heterocycle-based copolymers as active layer have long been ignored in solution-processable n-channel polymer field-effect transistors (PFETs) despite the long history of using OZ or TZ derivatives as the electron-injecting materials in organic light-emitting devices and their favorable electron affinities. Herein, we first report the synthesis and PFETs performance of two n-channel conjugated polymers bearing OZ- or TZ-based acceptor moieties, i.e., PNOZ and PNTZ, where simple thiophene units are utilized as the weak donors and additional alkylated-naphthalenediimides units are used as the second acceptors. A comparative study has been performed to reveal the effect of different heterocyclic acceptors on thermal properties, electronic properties, ordering structures, and carrier transport performance of the target polymers. It is found that both polymers possess low-lying LUMO values below -4.0 eV, indicating high electron affinity for both heterocycle-based polymers. Because of strong polarizable ability of sulfur atom in TZ heterocycle, PNTZ exhibits a red shift in maximal absorption and stronger molecular aggregation even in the diluted chlorobenzene solution as compared to the OZ-containing PNOZ. Surface morphological study reveals that a nodule-like surface with a rough surface morphology is observed clearly for PNOZ films, whereas PNTZ films display highly uniform surface morphology with well interconnected fiber-like polycrystalline grains. Investigation of PFETs performance indicates that both polymers afford air-stable n-channel transport characteristics. The uniform morphological structure and compact π-π stacking endow PNTZ with a high electron mobility of 0.36 cm2 V-1 s-1, much higher than that of PNOZ (0.026 cm2 V-1 s-1). These results manifest the feasibility in improving electron-transporting property simply by tuning heteroatom substitutes in n-channel polymers; further demostrate that TZ derivatives possess much superior potential for developing high-performance n-channel polymers compared to OZ derivatives.

12.
Org Lett ; 15(21): 5586-9, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24144299

RESUMO

A tandem directed metalation has been successfully applied to the preparation of thieno[2,3-f]benzofuran-4,8-dione, providing an efficient and facile approach to symmetrically and unsymmetrically functionalize the thieno[2,3-f]benzofuran core at the 2,6 positions as well as to introduce the electron-withdrawing or -donating groups (EWG or EDG) at its 4,8 positions. The presence of various functional groups makes late-stage derivatization attainable.

13.
Chem Commun (Camb) ; 49(37): 3857-9, 2013 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-23546042

RESUMO

A novel conjugated side-chain polymer (PBDT-TID), based on benzo[1,2-b:4,5-b']dithiophene (BDT) and isoindigo (ID) moieties, was designed and synthesized. The new polymer exhibited excellent microphase separation in active layers. Bulk heterojunction polymer solar cells fabricated from PBDT-TID and PC61BM showed promising power conversion efficiencies of 5.25% and 6.51% using conventional and inverted device structures, respectively.

14.
Chem Commun (Camb) ; 47(33): 9381-3, 2011 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-21779607

RESUMO

A new benzodithiophene-based copolymer PTG1 with dithienylbenzothiadiazole-vinylene side chains exhibits excellent film-forming ability, a deep HOMO energy level, and a good miscibility with PC(71)BM. Bulk heterojunction polymer solar cells fabricated from PTG1 and PC(71)BM showed a promising power conversion efficiency over 4.0%.

15.
Chem Commun (Camb) ; (18): 2499-501, 2009 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-19532869

RESUMO

Three novel organic dyes based on porphyrin derivatives were designed and synthesized for dye-sensitized solar cells, resulting in a maximum power conversion efficiency (eta) of 5.14% and a maximum IPCE value of 72% for a cell based on the dye.

16.
J Phys Chem B ; 113(13): 4203-8, 2009 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-19260694

RESUMO

A series of block copolymers containing nonconjugated spacer and 3D pi-pi stacking structure with simultaneous blue-, green-, and yellow-emitting units has been synthesized and characterized. The dependence of the energy transfer and electroluminescence (EL) properties of these block copolymers on the contents of oligo(phenylenevinylene)s has been investigated. The block copolymer (GEO8-BEO-YEO4) with 98.8% blue-emitting oligomer (BEO), 0.8% green-emitting oligomer (GEO), and 0.4% yellow-emitting oligomer (YEO) showed the best electroluminescent performance, exhibiting a maximum luminance of 2309 cd/m(2) and efficiency of 0.34 cd/A. The single-layer-polymer light-emitting diodes device based on GEO2-BEO-YEO4 emitted greenish white light with the CIE coordinates of (0.26, 0.37) at 10 V. The synergetic effect of the efficient energy transfer and 3D pi-pi stack of these block copolymers on the photoluminescent and electroluminescent properties are investigated.

17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(1): 145-8, 2005 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-15852841

RESUMO

2-octyl-1, 3-diphenol-1, 3-propdione was synthesized by phase transfer catalysis and its Sm complexes were prepared. These compounds were characterized by IR, EA, UV and 1H NMR; Sm complex and its mixture doped with PE and PVC show photoluminescence at 650 nm. There is excellent compatibility between Sm complex and plastics by the addition of long carbon chain. Therefore, Sm complex with long carbon chain is a superior light conversion agent with good compatibility in resins with emission wavelength suitable to the 643 and 660 nm for plants' photosynthesis.


Assuntos
Substâncias Luminescentes/química , Compostos Organometálicos/química , Plásticos/química , Samário/química , Catálise , Substâncias Luminescentes/síntese química , Medições Luminescentes/métodos , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Varredura , Estrutura Molecular , Compostos Organometálicos/síntese química , Fenóis/síntese química , Fenóis/química , Processos Fotoquímicos/efeitos da radiação , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 24(1): 18-20, 2004 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-15768966

RESUMO

3-Allyl-2,4-pentanedione (APD) was synthesized and its rare earth complexes were prepared. The compounds were characterized by EA, IR and 1H NMR. The sensitization of acetylacetone was changed by allyl, which became a novel ligand of Eu.


Assuntos
Eletroquímica/métodos , Medições Luminescentes/métodos , Metais Terras Raras/química , Pentanonas/química , Espectrofotometria Ultravioleta/métodos , Luminescência , Espectrometria de Fluorescência
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