In this work, star-shaped perylene bisimide(PBI) derivatives with spiro-aromatic cores linked with ethynyl units were developed as electron acceptors for non-fullerene organic solar cells. The ethynyl linkers were fou...In this work, star-shaped perylene bisimide(PBI) derivatives with spiro-aromatic cores linked with ethynyl units were developed as electron acceptors for non-fullerene organic solar cells. The ethynyl linkers were found to enhance the planarity of the conjugated backbone, resulting in high electron mobilities and near-infrared absorption. The ethynyl-linked PBI acceptors showed high power conversion efficiencies(PCEs) up to 4.27% due to the high short-circuit current density(Jsc) of 8.52 mA/cm^2 and fill factor(FF) of 0.59, while the PBI acceptor without ethynyl units provided a low PCE of 3.57% in nonfullerene solar cells. The results demonstrate that ethynyl units can be applied into designing new PBI electron acceptors with improved charge transport properties and photovoltaic performance.展开更多
Quantum-chemical calculations on some derivatives of [n]-prismanes expanded by ethynyl or ethenyl groups have been performed using density functional theory （DFT） method.Their geometric structures,electronic structu...Quantum-chemical calculations on some derivatives of [n]-prismanes expanded by ethynyl or ethenyl groups have been performed using density functional theory （DFT） method.Their geometric structures,electronic structures,vertical ionization potentials and vertical electron affinities have been obtained at the B3LYP/6-31G＊＊ level of theory.Meanwhile,the total strain energy has been investigated in detail and compared with [n]-prismane and other derivatives.The present paper has also computed the enthalpies of formation for different isomers so as to evaluate their thermal stabilities.展开更多
To develop efficient sensitizers for dye-sensitized solar cells(DSSCs),we recently reported doubly concerted companion(DCC)dye XW83 with a wrapped porphyrin sub-dye unit linked to an organic sub-dye unit through a fle...To develop efficient sensitizers for dye-sensitized solar cells(DSSCs),we recently reported doubly concerted companion(DCC)dye XW83 with a wrapped porphyrin sub-dye unit linked to an organic sub-dye unit through a flexible chain,which exhibits panchromatic absorption and excellent anti-aggregation ability.To further improve the absorption,we herein report XW87 and XW88 by inserting an ethynyl group into the organic sub-dye unit of XW83 near the donor and acceptor,respectively.For the corresponding organic dyes Z3 and Z4,the introduced ethynyl group improves their absorption,but induces aggravated charge recombination,leading to lowered power conversion efficiencies(PCEs).Similar to the organic dyes,the introduced ethynyl group improves the absorption of DCC dyes XW87 and XW88 as well.In addition,the ethynyl group near the acceptor of the organic sub-dye unit can be well protected by the long wrapping chains from the porphyrin unit.As a result,XW88 affords the highest JSC(21.84 mA/cm^(2)),V_(OC)(782 mV)and PCE(12.2%)among the DCC dyes.These results provide an effective method for developing efficient DSSC dyes by inserting an ethynyl group at a suitable position of a DCC dye.展开更多
Two copolymers of P1 and P2 comprising benzothiadiazole, 1,4-bis（dodecyloxy）-benzene units were synthesized by Sonogashira coupling polymerization based on ethynyl-linked 1,2,5,6-naphthalenediimide. Their thermal, o...Two copolymers of P1 and P2 comprising benzothiadiazole, 1,4-bis（dodecyloxy）-benzene units were synthesized by Sonogashira coupling polymerization based on ethynyl-linked 1,2,5,6-naphthalenediimide. Their thermal, optical, electrochemical as well as charge transport properties were studied. Bottom-gate top-contact organic field-effect transistors （OFETs） measurements of P1 and P2 thin films showed different charge transport behaviors. P1 displayed pure electron transport behaviors in OFETs with electron mobility up to 10^-3 cm^2·V-1·s^-1, while P2 exhibited hole transport features. The molecular structure analysis revealed that the structure of P1 has the acceptor-linker-acceptor＇ （A-L-A＇） characteristic, and P2 possesses the donor-linker-acceptor （D-L-A） structure feature. The results demonstrate that different molecular structures lead them to have distinct charge transport behaviors. In particular, the first pure electron transport copolymer in OFETs based on 1,2,5,6-naphthalenediimide is achieved.展开更多
The first cyclic molecule formation reactions from ethyne （C2H2）, initiated by ethynyl radical （C2H）, were studied by theoretical quantum mechanic. The study included the competition reaction between structure re-...The first cyclic molecule formation reactions from ethyne （C2H2）, initiated by ethynyl radical （C2H）, were studied by theoretical quantum mechanic. The study included the competition reaction between structure re-arrangement for the favourable ring-closure mechanism and ethyne addition in each step. The analysis was done by evaluating the energy difference of activation （AE）, entalphy （AH）, Gibbs （AG） of the optimized stable and transition molecules. The reaction temperatures were set at normal （T = 298 K） and combustion （T = 1200 K） condition.展开更多
Combining spin crossover(SCO)and fluorescence properties could respond to multiple physical stimulus and is meaningful for the development of switches and imaging tools.In this work,we present a new family of neutral ...Combining spin crossover(SCO)and fluorescence properties could respond to multiple physical stimulus and is meaningful for the development of switches and imaging tools.In this work,we present a new family of neutral mononuclear iron(Ⅱ)complexes,denoted as Fe(L^(1-3))_(2) and Fe(L^(3))_(2)·CH_(2)Cl_(2) with N_(4)O_(2) donor sets.These complexes were synthesized employing a series of tridentate Schiff base ligands,which contain an ethynyl group(HL^(1-3)=3-ethynyl-N′-((4-methylpyridin-2-yl)methylene)benzohydrazide(4MePAH-3EyBHZ,HL^(1)),3-ethynyl-N′-((4-methoxylpyridin-2-yl)methylene)benzohydrazide(4OMe-PAH-3EyBHZ,HL^(2)),3-ethynyl-N′-((5-methylpyridin-2-yl)methylene)benzohydrazide(5MePAH-3EyBHZ,HL^(3))).Variable-temperature magnetic susceptibility measurements revealed that Fe(L^(1))_(2) exhibits an abrupt and complete SCO with characteristic temperature T_(1/2↓)=176 K and T_(1/2↑)=178 K;Fe(L^(2))_(2) exhibits an abrupt and complete SCO with T_(1/2↓)=214 K and T_(1/2↑)=219 K;Fe(L^(3))_(2) exhibits an abrupt and complete SCO with T_(1/2↓)=218 K and T_(1/2↑)=226 K.The partial conformational inversion is observed between the high spin and low spin state of Fe(L^(2))_(2) evidenced by the variable-temperature single-crystal X-ray diffraction analysis.An unusual increase of emission intensity was observed in the fluorescence spectra of Fe(L^(1))_(2) and Fe(L^(2))_(2) during the heating SCO process.These findings are both valuable in the study of spin-fluorescence interaction and synthesis of new multifunctional SCO complexes.展开更多
基金supported by the Recruitment Program of Global Youth Experts of Chinasupported by the National Natural Science Foundation of China(Nos. 21574138, 51603209 and 91633301)the Strategic Priority Research Program(No. XDB12030200) of the Chinese Academy of Sciences
文摘In this work, star-shaped perylene bisimide(PBI) derivatives with spiro-aromatic cores linked with ethynyl units were developed as electron acceptors for non-fullerene organic solar cells. The ethynyl linkers were found to enhance the planarity of the conjugated backbone, resulting in high electron mobilities and near-infrared absorption. The ethynyl-linked PBI acceptors showed high power conversion efficiencies(PCEs) up to 4.27% due to the high short-circuit current density(Jsc) of 8.52 mA/cm^2 and fill factor(FF) of 0.59, while the PBI acceptor without ethynyl units provided a low PCE of 3.57% in nonfullerene solar cells. The results demonstrate that ethynyl units can be applied into designing new PBI electron acceptors with improved charge transport properties and photovoltaic performance.
文摘Quantum-chemical calculations on some derivatives of [n]-prismanes expanded by ethynyl or ethenyl groups have been performed using density functional theory （DFT） method.Their geometric structures,electronic structures,vertical ionization potentials and vertical electron affinities have been obtained at the B3LYP/6-31G＊＊ level of theory.Meanwhile,the total strain energy has been investigated in detail and compared with [n]-prismane and other derivatives.The present paper has also computed the enthalpies of formation for different isomers so as to evaluate their thermal stabilities.
基金financially supported by the National Natural Science Foundation of China(Nos.22131005,22201074,22075077 and 21971063)the Fundamental Research Funds for the Central Universities,Program of Shanghai Academic Research Leader(No.20XD1401400)+1 种基金Shanghai Rising-Star Program(No.23QA1402100)Natural Science Foundation of Shanghai(Nos.23ZR1415600,22ZR1416100).
文摘To develop efficient sensitizers for dye-sensitized solar cells(DSSCs),we recently reported doubly concerted companion(DCC)dye XW83 with a wrapped porphyrin sub-dye unit linked to an organic sub-dye unit through a flexible chain,which exhibits panchromatic absorption and excellent anti-aggregation ability.To further improve the absorption,we herein report XW87 and XW88 by inserting an ethynyl group into the organic sub-dye unit of XW83 near the donor and acceptor,respectively.For the corresponding organic dyes Z3 and Z4,the introduced ethynyl group improves their absorption,but induces aggravated charge recombination,leading to lowered power conversion efficiencies(PCEs).Similar to the organic dyes,the introduced ethynyl group improves the absorption of DCC dyes XW87 and XW88 as well.In addition,the ethynyl group near the acceptor of the organic sub-dye unit can be well protected by the long wrapping chains from the porphyrin unit.As a result,XW88 affords the highest JSC(21.84 mA/cm^(2)),V_(OC)(782 mV)and PCE(12.2%)among the DCC dyes.These results provide an effective method for developing efficient DSSC dyes by inserting an ethynyl group at a suitable position of a DCC dye.
基金financially supported by the National Natural Science Foundation of China(No.21674126)the"Strategic Priority Research Program"(No.XDB12010100)the Shanghai Science and Technology Committee(No.16JC1400603)
文摘Two copolymers of P1 and P2 comprising benzothiadiazole, 1,4-bis（dodecyloxy）-benzene units were synthesized by Sonogashira coupling polymerization based on ethynyl-linked 1,2,5,6-naphthalenediimide. Their thermal, optical, electrochemical as well as charge transport properties were studied. Bottom-gate top-contact organic field-effect transistors （OFETs） measurements of P1 and P2 thin films showed different charge transport behaviors. P1 displayed pure electron transport behaviors in OFETs with electron mobility up to 10^-3 cm^2·V-1·s^-1, while P2 exhibited hole transport features. The molecular structure analysis revealed that the structure of P1 has the acceptor-linker-acceptor＇ （A-L-A＇） characteristic, and P2 possesses the donor-linker-acceptor （D-L-A） structure feature. The results demonstrate that different molecular structures lead them to have distinct charge transport behaviors. In particular, the first pure electron transport copolymer in OFETs based on 1,2,5,6-naphthalenediimide is achieved.
文摘The first cyclic molecule formation reactions from ethyne （C2H2）, initiated by ethynyl radical （C2H）, were studied by theoretical quantum mechanic. The study included the competition reaction between structure re-arrangement for the favourable ring-closure mechanism and ethyne addition in each step. The analysis was done by evaluating the energy difference of activation （AE）, entalphy （AH）, Gibbs （AG） of the optimized stable and transition molecules. The reaction temperatures were set at normal （T = 298 K） and combustion （T = 1200 K） condition.
基金supported by the National Natural Science Foundation of China(grant nos.21971006 and 22131003).
文摘Combining spin crossover(SCO)and fluorescence properties could respond to multiple physical stimulus and is meaningful for the development of switches and imaging tools.In this work,we present a new family of neutral mononuclear iron(Ⅱ)complexes,denoted as Fe(L^(1-3))_(2) and Fe(L^(3))_(2)·CH_(2)Cl_(2) with N_(4)O_(2) donor sets.These complexes were synthesized employing a series of tridentate Schiff base ligands,which contain an ethynyl group(HL^(1-3)=3-ethynyl-N′-((4-methylpyridin-2-yl)methylene)benzohydrazide(4MePAH-3EyBHZ,HL^(1)),3-ethynyl-N′-((4-methoxylpyridin-2-yl)methylene)benzohydrazide(4OMe-PAH-3EyBHZ,HL^(2)),3-ethynyl-N′-((5-methylpyridin-2-yl)methylene)benzohydrazide(5MePAH-3EyBHZ,HL^(3))).Variable-temperature magnetic susceptibility measurements revealed that Fe(L^(1))_(2) exhibits an abrupt and complete SCO with characteristic temperature T_(1/2↓)=176 K and T_(1/2↑)=178 K;Fe(L^(2))_(2) exhibits an abrupt and complete SCO with T_(1/2↓)=214 K and T_(1/2↑)=219 K;Fe(L^(3))_(2) exhibits an abrupt and complete SCO with T_(1/2↓)=218 K and T_(1/2↑)=226 K.The partial conformational inversion is observed between the high spin and low spin state of Fe(L^(2))_(2) evidenced by the variable-temperature single-crystal X-ray diffraction analysis.An unusual increase of emission intensity was observed in the fluorescence spectra of Fe(L^(1))_(2) and Fe(L^(2))_(2) during the heating SCO process.These findings are both valuable in the study of spin-fluorescence interaction and synthesis of new multifunctional SCO complexes.
