Reorganization energy(RE)is closely related to the charge transport properties and is one of the important parameters for screening novel organic semiconductors(OSCs).With the rise of data-driven technology,accurate a...Reorganization energy(RE)is closely related to the charge transport properties and is one of the important parameters for screening novel organic semiconductors(OSCs).With the rise of data-driven technology,accurate and efficient machine learning(ML)models for high-throughput screening novel organic molecules play an important role in the boom of material science.Comparing different molecular descriptors and algorithms,we construct a reasonable algorithm framework with molecular graphs to describe the compositional structure,convolutional neural networks to extract material features,and subsequently embedded fully connected neural networks to establish the mapping between features and predicted properties.With our well-designed judicious training pattern about feature-guided stratified random sampling,we have obtained a high-precision and robust reorganization energy prediction model,which can be used as one of the important descriptors for rapid screening potential OSCs.The root-meansquare error(RMSE)and the squared Pearson correlation coefficient(R^(2))of this model are 2.6 me V and0.99,respectively.More importantly,we confirm and emphasize that training pattern plays a crucial role in constructing supreme ML models.We are calling for more attention to designing innovative judicious training patterns in addition to high-quality databases,efficient material feature engineering and algorithm framework construction.展开更多
A novel algorithm was designed and implemented to realize the numerical calculation of the solvent reorganization energy for electron transfer reactions, on the basis of nonequilibrium solvation theory and the dielect...A novel algorithm was designed and implemented to realize the numerical calculation of the solvent reorganization energy for electron transfer reactions, on the basis of nonequilibrium solvation theory and the dielectric polarizable continuum model. Applying the procedure to the well-investigated intramoleeular electron transfer in biphenyl-androstane-naphthyl and biphenyl-androstane-phenanthryl systems, the numerical results of solvent reorganization energy were determined to be around 60 k J/mol, in good agreement with experimental data. Koopman＇s theorem was adopted for the calculation of the electron transfer coupling element, associated with the linear reaction coordinate approximation. The values for this quantity obtained are acceptable when compared with experimental results.展开更多
Reported here are several new calculation methods for the inner-sphere reorganization energy of hydrated metal ions involved in electron transfer processes.It is based on the self-exchange model of reorganization and ...Reported here are several new calculation methods for the inner-sphere reorganization energy of hydrated metal ions involved in electron transfer processes.It is based on the self-exchange model of reorganization and utilizes the more exact potential functions between central metal ion and the inner-sphere ligands.The parameters involved are determined via the spectroscopic and thermodynamic data.The predictions of the inner-sphere reorganization energies from those models agree well with the photoemission experimental results.展开更多
On the basis of the-improved self-exchange model of reorganization phenomenon and accurate potential functions from ab initio calculation at HFSCF 6-31G* and DZP levels a new calculation method was,presented for the i...On the basis of the-improved self-exchange model of reorganization phenomenon and accurate potential functions from ab initio calculation at HFSCF 6-31G* and DZP levels a new calculation method was,presented for the inner-sphere reorganization energy, values for diatomic molecular redox couples in gas phase electron transfer process have been calculated. Results agree well with the experimental data, and the effectiveness and importance of this method have been demonstrated for calculation of inner-sphere reorganization energy in gas phase electron transfer process.展开更多
A new ab-initio method of computing reorganization energy (RE) for the electron transfer (ET) reaction between M-H and M+-H system is presented. Values of RE from precise RE definition and the George-Griffith-Marcus (...A new ab-initio method of computing reorganization energy (RE) for the electron transfer (ET) reaction between M-H and M+-H system is presented. Values of RE from precise RE definition and the George-Griffith-Marcus (GGM) model were obtained and compared with the RE obtained from the experimental spectroscopic data. Results show that in the gaseous phase, ET reactions by the new method can give better values than classical GGM model.展开更多
A novel two-dimensional A-D-A acceptor named as CH8 with four electron-withdrawing end units has been successfully designed and synthesized.The enlarged conjugation in two directions renders CH8 exhibit an extremely l...A novel two-dimensional A-D-A acceptor named as CH8 with four electron-withdrawing end units has been successfully designed and synthesized.The enlarged conjugation in two directions renders CH8 exhibit an extremely low electron reorganization energy of 98 meV,which makes CH8 a potential candidate for outstanding organic semiconductor material.When blended with PM6,a considerate power conversion efficiency of 9.37%along with a high open-circuit voltage(V_(oc))0.889 V and low energy loss(E_(loss))below 0.6 eV is achieved.These results indicate that the two-dimensional A-D-A molecule with four electron-withdrawing end units is an effective molecular design strategy to achieve lower voltage loss and also possible high performance for organic photovoltaics if ideal morphology could be achieved.展开更多
Concerning the theoretical estimation of internal reorganization energy contributed by the tortional motion between biphenyl and biphenyl anion radical, direct calculation of self-exchange electron transfer reaction w...Concerning the theoretical estimation of internal reorganization energy contributed by the tortional motion between biphenyl and biphenyl anion radical, direct calculation of self-exchange electron transfer reaction was investigated. With the introduction of a proper average bond length and angle parameters <bond Bp>, a multiple step relaxation Nelson method was developed to deal with the torsional reorganization energy. Based on the above model, an estimation of pure torsional reorganization energy λ t,p with an approximation of λ t,1 was achieved. The results of 0.140 and 0.125 eV of torsional reorganization energy for a cross-reaction at the levels of 4-31G and HP/DZP, respectively, are in good agreement with the value of 0.13 eV obtained by Miller et al. from the rate measurements. This implies the efficiency and validity of our method to estimate the reorganization energy contributed by pure torsional motion of Bp.展开更多
According to the nonequilibrium solvation theory studies, a constrained equilibrium principle is introduced and applied to the derivations of the nonequilibrium solvation energy, and a reasonable expression of the spe...According to the nonequilibrium solvation theory studies, a constrained equilibrium principle is introduced and applied to the derivations of the nonequilibrium solvation energy, and a reasonable expression of the spectral shift of the electronic absorption spectra is deduced. Furthermore, the lowest transition of p-nitroaniline （pNA） in water is investigated by time-dependent density functional theory method. In addition, the details of excited state properties of pNA are discussed. Using our novel expression of the spectral shift, the value of -0.99 eV is obtained for π→π^＊ transition in water, which is in good agreement with the available experimental result of -0.98 eV.展开更多
A series of CH2, NH, O, and Se substituted 2,1,3-benzothiadiazote derivatives have been designed and investigated computationally to elucidate their potential as organic light-emitting materials for organic light-emit...A series of CH2, NH, O, and Se substituted 2,1,3-benzothiadiazote derivatives have been designed and investigated computationally to elucidate their potential as organic light-emitting materials for organic light-emitting diodes. Both ab initio Hartree-Foek and hybrid density functional methods are used. It is found that S by CH2, NH, O, and Se makes it possible transport properties of the pristine molecule adjusting the central aromatic ring by replacing to fine-tune the electronic, optical, and charge展开更多
DFT and TD-DFT calculations of HOMO and LUMO energies and photovoltaic properties are carried out on four selected pentathiophene donor and one IDIC-4F acceptor molecules using B3LYP and PBE0 functionals for the groun...DFT and TD-DFT calculations of HOMO and LUMO energies and photovoltaic properties are carried out on four selected pentathiophene donor and one IDIC-4F acceptor molecules using B3LYP and PBE0 functionals for the ground state energy calculations and CAM-B3LYP functional for the excited state calculations.The discrepancy between the calculated and experimental energies is reduced by correlating them with a linear fit.The fitted energies of HOMO and LUMO are used to calculate the Voc of an OSC based on these donors and acceptor blend and compared with experimental values.Using the Scharber model the calculated PCE of the donor-acceptor molecules agree with the experiment.It has been found that fluorine substitution can be used to improve charge transport by reducing the electron and hole reorganization energies of the molecules.It is also found that the introduction of fluorine onto the donor pentathiophene unit of the donor molecule results in a change of polarity of the distributed charges in the molecule due to the high electronegativity of the fluorine atom.The quantum chemical potential(μ),chemical hardness(η)and electronegativity(χ),and electrostatic potential maps(EPMs)are also calculated to identify different charge distribution regions in all five molecules.展开更多
Comparison in electron transfer(ET) processes from decamethyferrocene(DMFe) in nitrobenzene(NB) to ferric ion in aqueous phase was investigated for the first time by the scanning electrochemical microscopy(SECM).As co...Comparison in electron transfer(ET) processes from decamethyferrocene(DMFe) in nitrobenzene(NB) to ferric ion in aqueous phase was investigated for the first time by the scanning electrochemical microscopy(SECM).As compared with the system of Fe(CN)_6^(3-)-DMFe,the ET rate obtained from Fe^(3+)-DMFe was lower in spite of larger driving force,which may arise from the effect of reorganization energy.Otherwise,the effect of common ion on rate constants was also probed and results suggested additional complexit...展开更多
Influence of intramolecular π-π interaction on the luminescent properties of thermally activated delayed fluorescence（TADF） molecule（3, 5-bis（3,6-di-tert-butyl-9 H-carbazol-9-yl）-phenyl）（pyridin-4-yl） methan...Influence of intramolecular π-π interaction on the luminescent properties of thermally activated delayed fluorescence（TADF） molecule（3, 5-bis（3,6-di-tert-butyl-9 H-carbazol-9-yl）-phenyl）（pyridin-4-yl） methanone（DTCBPY） is theoretically studied by using the density functional theory（DFT） and time-dependent density functional theory（TD-DFT）.Four conformations（named as A, B, C, and D） of the DTCBPY can be found by relax scanning, and the configuration C corresponds to the luminescent molecule detected experimentally. Besides, we calculate the proportion of each conformation by Boltzmann distribution, high configuration ratios（44% and 52%） can be found for C and D. Moreover, C and D are found to exist with an intramolecular π-π interaction between one donor and the acceptor; the intramolecular interaction brings a smaller Huang-Rhys factor and reduced reorganization energy. Our work presents a rational explanation for the experimental results and demonstrates the importance of the intramolecular π-π interaction to the photophysical properties of TADF molecules.展开更多
Dimeric fused-ring electron acceptors(DFREAs)have attracted much attention due to the combined advantages of their monomeric and polymeric acceptors,including a well-defined molecular structure,excellent repeatability...Dimeric fused-ring electron acceptors(DFREAs)have attracted much attention due to the combined advantages of their monomeric and polymeric acceptors,including a well-defined molecular structure,excellent repeatability,and stable morphology.However,the additionally introduced single-bonds during dimerization may result in a twisted backbone of DFREAs,which is detrimental to intermolecular packing and charge transport.Herein,three DFREAs are designed and synthesized,in which DFREA conformations were systematically tuned via adjusting the intensities of intramolecular noncovalent interactions(INIs)to achieve high-performance organic solar cells(OSCs).Theoretical and experimental results show that the gradual introduction of S…F INIs can continuously improve molecular planarity and rigidity,resulting in reduced reorganization energies,ordered packing mode,and enhanced crystallization of DFREAs.Benefiting from the incorporation of fourfold S…F INIs,DYF-TF-based binary OSCs show a record high efficiency of 18.26%with an extremely low energy loss(0.493 eV)for DFREAbased OSCs.In addition,DYF-TF-based OSCs exhibited good long-term stability with a T_(80%)lifetime of 2681 h,and the power conversion efficiency of the DYF-TF-based ternary device is further enhanced to 18.73%.This contribution demonstrates the great potential of the INIs strategy in achieving excellent DFREAs materials.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
Theoretical investigations have been performed to explore the variation in electronic,optical,and charge transport properties upon the change of the chemical composition along the backbone in 2,1,3-benzothiadiazole（...Theoretical investigations have been performed to explore the variation in electronic,optical,and charge transport properties upon the change of the chemical composition along the backbone in 2,1,3-benzothiadiazole（BTD）-based derivative.Narrow difference between hole and electron transportations with the charge hopping model indicates studied BTD-based derivative can be used as good ambipolar transport material in organic light-emitting diodes.展开更多
Charge carrier mobility is one of the most significant properties for organic semiconductors. In this work, the electronic structures and charge transport properties of 9,10-bis（（E）-2-（pyrid-n-yl）vinyl） （n=2, 3...Charge carrier mobility is one of the most significant properties for organic semiconductors. In this work, the electronic structures and charge transport properties of 9,10-bis（（E）-2-（pyrid-n-yl）vinyl） （n=2, 3, 4） anthracene （BP2VA, BP3VA and BP4VA） were investigated via the analysis of the molecular geometry, the reorganization en- ergy, the frontier orbital and density of state, as well as the electronic coupling and the charge mobility. The results indicated that the linkage between 9,10-divinyl anthracene unit and pyridine （ortho-, meta- and para-） influenced not only the intra-molecular conformation （i.e., the reorganization energies）, but also the intermolecular interaction （i.e., transfer integrals）, and finally the charge mobility of the molecules. It is also found that： （1） The calculated charge mobilties of holes are dozens of times higher than those of electrons for the three molecules. （2） The charge mobilities of hole and electron of the three molecules display the trend： μBP4VA〉μBPZVA〉μBP3VA, and the hole mobility of BP4VA is as high as as-cm^2/（V·s）.展开更多
As a successive work of our previous paper, 1 the electron transfer matrix element (V rp) in the oxidation of the simplified model molecule of α-amino carbon-centered radical by O 2 has been investigated wi...As a successive work of our previous paper, 1 the electron transfer matrix element (V rp) in the oxidation of the simplified model molecule of α-amino carbon-centered radical by O 2 has been investigated with ab initio calculation at the level of UHF/6-31++G**. Based on the optimized geometries of the reactant and the ion-pair complex obtained previously, the reaction heat and the inner reorganization energy have been obtained by constructing the potential energy curves of reactant and product states considering the solvent effect with the conductor-like screening model (COSMO). The solvent reorganization energy has been estimated using Lippert-Mataga relationship. The calculated results show that the value of V rp is several times larger than that of RT, which means that the model reaction is an adiabatic one. Theoretical investigation indicates that the solvent effect on the direct electron transfer (ET) process of oxidation of α-amino carbon-centered radical by oxygen is remarkable.展开更多
基金financially supported by the Ministry of Science and Technology of China (2017YFA0204503 and 2018YFA0703200)the National Natural Science Foundation of China (52121002,U21A6002 and 22003046)+1 种基金the Tianjin Natural Science Foundation (20JCJQJC00300)“A Multi-Scale and High-Efficiency Computing Platform for Advanced Functional Materials”program,funded by Haihe Laboratory in Tianjin (22HHXCJC00007)。
文摘Reorganization energy(RE)is closely related to the charge transport properties and is one of the important parameters for screening novel organic semiconductors(OSCs).With the rise of data-driven technology,accurate and efficient machine learning(ML)models for high-throughput screening novel organic molecules play an important role in the boom of material science.Comparing different molecular descriptors and algorithms,we construct a reasonable algorithm framework with molecular graphs to describe the compositional structure,convolutional neural networks to extract material features,and subsequently embedded fully connected neural networks to establish the mapping between features and predicted properties.With our well-designed judicious training pattern about feature-guided stratified random sampling,we have obtained a high-precision and robust reorganization energy prediction model,which can be used as one of the important descriptors for rapid screening potential OSCs.The root-meansquare error(RMSE)and the squared Pearson correlation coefficient(R^(2))of this model are 2.6 me V and0.99,respectively.More importantly,we confirm and emphasize that training pattern plays a crucial role in constructing supreme ML models.We are calling for more attention to designing innovative judicious training patterns in addition to high-quality databases,efficient material feature engineering and algorithm framework construction.
文摘A novel algorithm was designed and implemented to realize the numerical calculation of the solvent reorganization energy for electron transfer reactions, on the basis of nonequilibrium solvation theory and the dielectric polarizable continuum model. Applying the procedure to the well-investigated intramoleeular electron transfer in biphenyl-androstane-naphthyl and biphenyl-androstane-phenanthryl systems, the numerical results of solvent reorganization energy were determined to be around 60 k J/mol, in good agreement with experimental data. Koopman＇s theorem was adopted for the calculation of the electron transfer coupling element, associated with the linear reaction coordinate approximation. The values for this quantity obtained are acceptable when compared with experimental results.
基金Supported by the Natural Science Foundation of Shandong Province
文摘Reported here are several new calculation methods for the inner-sphere reorganization energy of hydrated metal ions involved in electron transfer processes.It is based on the self-exchange model of reorganization and utilizes the more exact potential functions between central metal ion and the inner-sphere ligands.The parameters involved are determined via the spectroscopic and thermodynamic data.The predictions of the inner-sphere reorganization energies from those models agree well with the photoemission experimental results.
文摘On the basis of the-improved self-exchange model of reorganization phenomenon and accurate potential functions from ab initio calculation at HFSCF 6-31G* and DZP levels a new calculation method was,presented for the inner-sphere reorganization energy, values for diatomic molecular redox couples in gas phase electron transfer process have been calculated. Results agree well with the experimental data, and the effectiveness and importance of this method have been demonstrated for calculation of inner-sphere reorganization energy in gas phase electron transfer process.
文摘A new ab-initio method of computing reorganization energy (RE) for the electron transfer (ET) reaction between M-H and M+-H system is presented. Values of RE from precise RE definition and the George-Griffith-Marcus (GGM) model were obtained and compared with the RE obtained from the experimental spectroscopic data. Results show that in the gaseous phase, ET reactions by the new method can give better values than classical GGM model.
基金financially supported by the National Natural Science Foundation of China (Nos. 21935007, 52025033 and 51873089)Ministry of Science and Technology (No. 2019YFA0705900) of China,Tianjin city (No. 20JCZDJC00740)111 Project (No. B12015)
文摘A novel two-dimensional A-D-A acceptor named as CH8 with four electron-withdrawing end units has been successfully designed and synthesized.The enlarged conjugation in two directions renders CH8 exhibit an extremely low electron reorganization energy of 98 meV,which makes CH8 a potential candidate for outstanding organic semiconductor material.When blended with PM6,a considerate power conversion efficiency of 9.37%along with a high open-circuit voltage(V_(oc))0.889 V and low energy loss(E_(loss))below 0.6 eV is achieved.These results indicate that the two-dimensional A-D-A molecule with four electron-withdrawing end units is an effective molecular design strategy to achieve lower voltage loss and also possible high performance for organic photovoltaics if ideal morphology could be achieved.
文摘Concerning the theoretical estimation of internal reorganization energy contributed by the tortional motion between biphenyl and biphenyl anion radical, direct calculation of self-exchange electron transfer reaction was investigated. With the introduction of a proper average bond length and angle parameters <bond Bp>, a multiple step relaxation Nelson method was developed to deal with the torsional reorganization energy. Based on the above model, an estimation of pure torsional reorganization energy λ t,p with an approximation of λ t,1 was achieved. The results of 0.140 and 0.125 eV of torsional reorganization energy for a cross-reaction at the levels of 4-31G and HP/DZP, respectively, are in good agreement with the value of 0.13 eV obtained by Miller et al. from the rate measurements. This implies the efficiency and validity of our method to estimate the reorganization energy contributed by pure torsional motion of Bp.
基金ACKNOWLEDGMENTS This work was supported Science Foundation of China by the National Natural （No.91016002）.
文摘According to the nonequilibrium solvation theory studies, a constrained equilibrium principle is introduced and applied to the derivations of the nonequilibrium solvation energy, and a reasonable expression of the spectral shift of the electronic absorption spectra is deduced. Furthermore, the lowest transition of p-nitroaniline （pNA） in water is investigated by time-dependent density functional theory method. In addition, the details of excited state properties of pNA are discussed. Using our novel expression of the spectral shift, the value of -0.99 eV is obtained for π→π^＊ transition in water, which is in good agreement with the available experimental result of -0.98 eV.
文摘A series of CH2, NH, O, and Se substituted 2,1,3-benzothiadiazote derivatives have been designed and investigated computationally to elucidate their potential as organic light-emitting materials for organic light-emitting diodes. Both ab initio Hartree-Foek and hybrid density functional methods are used. It is found that S by CH2, NH, O, and Se makes it possible transport properties of the pristine molecule adjusting the central aromatic ring by replacing to fine-tune the electronic, optical, and charge
文摘DFT and TD-DFT calculations of HOMO and LUMO energies and photovoltaic properties are carried out on four selected pentathiophene donor and one IDIC-4F acceptor molecules using B3LYP and PBE0 functionals for the ground state energy calculations and CAM-B3LYP functional for the excited state calculations.The discrepancy between the calculated and experimental energies is reduced by correlating them with a linear fit.The fitted energies of HOMO and LUMO are used to calculate the Voc of an OSC based on these donors and acceptor blend and compared with experimental values.Using the Scharber model the calculated PCE of the donor-acceptor molecules agree with the experiment.It has been found that fluorine substitution can be used to improve charge transport by reducing the electron and hole reorganization energies of the molecules.It is also found that the introduction of fluorine onto the donor pentathiophene unit of the donor molecule results in a change of polarity of the distributed charges in the molecule due to the high electronegativity of the fluorine atom.The quantum chemical potential(μ),chemical hardness(η)and electronegativity(χ),and electrostatic potential maps(EPMs)are also calculated to identify different charge distribution regions in all five molecules.
基金supported by the National Natural Science Foundation of China(No.20875077,No.20775060 and No.20927004)the Natural Science Foundation of Gansu(No.0701RJZA109 and No.0803RJZA105)Key Projects of Scientific Research Base of Department of Education,Gansu Province(No.08zx-07).
文摘Comparison in electron transfer(ET) processes from decamethyferrocene(DMFe) in nitrobenzene(NB) to ferric ion in aqueous phase was investigated for the first time by the scanning electrochemical microscopy(SECM).As compared with the system of Fe(CN)_6^(3-)-DMFe,the ET rate obtained from Fe^(3+)-DMFe was lower in spite of larger driving force,which may arise from the effect of reorganization energy.Otherwise,the effect of common ion on rate constants was also probed and results suggested additional complexit...
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11374195 and 21403133)Taishan Scholar Project of Shandong Normal University,China+1 种基金the Promotive Research Fund for Excellent Young and Middle-aged Scientists of Shandong Province,China(Grant No.BS2014cl001)the China Postdoctoral Science Foundation(Grant No.2014M560571)
文摘Influence of intramolecular π-π interaction on the luminescent properties of thermally activated delayed fluorescence（TADF） molecule（3, 5-bis（3,6-di-tert-butyl-9 H-carbazol-9-yl）-phenyl）（pyridin-4-yl） methanone（DTCBPY） is theoretically studied by using the density functional theory（DFT） and time-dependent density functional theory（TD-DFT）.Four conformations（named as A, B, C, and D） of the DTCBPY can be found by relax scanning, and the configuration C corresponds to the luminescent molecule detected experimentally. Besides, we calculate the proportion of each conformation by Boltzmann distribution, high configuration ratios（44% and 52%） can be found for C and D. Moreover, C and D are found to exist with an intramolecular π-π interaction between one donor and the acceptor; the intramolecular interaction brings a smaller Huang-Rhys factor and reduced reorganization energy. Our work presents a rational explanation for the experimental results and demonstrates the importance of the intramolecular π-π interaction to the photophysical properties of TADF molecules.
基金support from the National Nature Science Foundation of China(grant nos.51925306,52103352,52120105006)National Key R&D Program of China(grant no.2018FYA 0305800)+3 种基金Key Research Program of Chinese Academy of Sciences(grant no.XDPB08-2)the Strategic Priority Research Program of Chinese Academy of Sciences(grant no.XDB28000000)the Youth Innovation Promotion Association of Chinese Academy of Sciences(grant no.2022165)the Fundamental Research Funds for the Central Universities.DFT results described in this article were obtained from the National Supercomputing Center in Shenzhen(Shenzhen Cloud Computing Center).
文摘Dimeric fused-ring electron acceptors(DFREAs)have attracted much attention due to the combined advantages of their monomeric and polymeric acceptors,including a well-defined molecular structure,excellent repeatability,and stable morphology.However,the additionally introduced single-bonds during dimerization may result in a twisted backbone of DFREAs,which is detrimental to intermolecular packing and charge transport.Herein,three DFREAs are designed and synthesized,in which DFREA conformations were systematically tuned via adjusting the intensities of intramolecular noncovalent interactions(INIs)to achieve high-performance organic solar cells(OSCs).Theoretical and experimental results show that the gradual introduction of S…F INIs can continuously improve molecular planarity and rigidity,resulting in reduced reorganization energies,ordered packing mode,and enhanced crystallization of DFREAs.Benefiting from the incorporation of fourfold S…F INIs,DYF-TF-based binary OSCs show a record high efficiency of 18.26%with an extremely low energy loss(0.493 eV)for DFREAbased OSCs.In addition,DYF-TF-based OSCs exhibited good long-term stability with a T_(80%)lifetime of 2681 h,and the power conversion efficiency of the DYF-TF-based ternary device is further enhanced to 18.73%.This contribution demonstrates the great potential of the INIs strategy in achieving excellent DFREAs materials.
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supports from the Education Office of Jilin Province(No2010142)Institute Foundation of Siping City(No2010009) are gratefully acknowledged
文摘Theoretical investigations have been performed to explore the variation in electronic,optical,and charge transport properties upon the change of the chemical composition along the backbone in 2,1,3-benzothiadiazole（BTD）-based derivative.Narrow difference between hole and electron transportations with the charge hopping model indicates studied BTD-based derivative can be used as good ambipolar transport material in organic light-emitting diodes.
文摘Charge carrier mobility is one of the most significant properties for organic semiconductors. In this work, the electronic structures and charge transport properties of 9,10-bis（（E）-2-（pyrid-n-yl）vinyl） （n=2, 3, 4） anthracene （BP2VA, BP3VA and BP4VA） were investigated via the analysis of the molecular geometry, the reorganization en- ergy, the frontier orbital and density of state, as well as the electronic coupling and the charge mobility. The results indicated that the linkage between 9,10-divinyl anthracene unit and pyridine （ortho-, meta- and para-） influenced not only the intra-molecular conformation （i.e., the reorganization energies）, but also the intermolecular interaction （i.e., transfer integrals）, and finally the charge mobility of the molecules. It is also found that： （1） The calculated charge mobilties of holes are dozens of times higher than those of electrons for the three molecules. （2） The charge mobilities of hole and electron of the three molecules display the trend： μBP4VA〉μBPZVA〉μBP3VA, and the hole mobility of BP4VA is as high as as-cm^2/（V·s）.
文摘As a successive work of our previous paper, 1 the electron transfer matrix element (V rp) in the oxidation of the simplified model molecule of α-amino carbon-centered radical by O 2 has been investigated with ab initio calculation at the level of UHF/6-31++G**. Based on the optimized geometries of the reactant and the ion-pair complex obtained previously, the reaction heat and the inner reorganization energy have been obtained by constructing the potential energy curves of reactant and product states considering the solvent effect with the conductor-like screening model (COSMO). The solvent reorganization energy has been estimated using Lippert-Mataga relationship. The calculated results show that the value of V rp is several times larger than that of RT, which means that the model reaction is an adiabatic one. Theoretical investigation indicates that the solvent effect on the direct electron transfer (ET) process of oxidation of α-amino carbon-centered radical by oxygen is remarkable.
