A charge transfer complex(CTC)-enabled photoreduction of ether phosphonium salts for the generation of oxyalkyl radicals was described.The photoreduction provides a convenient method to achieve selective oxyalkylation...A charge transfer complex(CTC)-enabled photoreduction of ether phosphonium salts for the generation of oxyalkyl radicals was described.The photoreduction provides a convenient method to achieve selective oxyalkylation of enamides with broad substrate scope.The method features operational simplicity,mild and inherent green conditions.展开更多
Two charge-transfer complexes of 2a and 2b of Keggin type were synthesized and characterized by elemental analysis, IR spectra, UV spectra, XRD, TG-DSC; and were compared with Hquin-PW12. The primary structure of the...Two charge-transfer complexes of 2a and 2b of Keggin type were synthesized and characterized by elemental analysis, IR spectra, UV spectra, XRD, TG-DSC; and were compared with Hquin-PW12. The primary structure of the heteropolyanions had not been changed after the formation of the charge transfer complexes.展开更多
C<sub>60</sub> is the third form of elementary C, which was discovered in recent years.In C<sub>60</sub>, each C atom links with three adjacent C atoms in terms of sp<sup>2</sup>-li...C<sub>60</sub> is the third form of elementary C, which was discovered in recent years.In C<sub>60</sub>, each C atom links with three adjacent C atoms in terms of sp<sup>2</sup>-like hybridorbitals, in which there are two long bonds and one short bond. At present, sincemacro-quantity of C<sub>60</sub> is able to be produced with simple method, interest instudy on C<sub>60</sub> shifts to its chemical properties from the structure. (P(C<sub>6</sub>H<sub>5</sub>)<sub>3</sub>)<sub>2</sub>Ptand C<sub>60</sub> themselves are stable valence-saturated molecules, however, they can form sta-ble complexes through the charge transfer, in which (P(C<sub>6</sub>H<sub>5</sub>)<sub>3</sub>)<sub>2</sub> Pt is complexed展开更多
Molecular doping has become a widely used method to modulate the electric performance of organic semiconductors(OSC).Highly effective charge transfer during molecular doping is desired to achieve ideal electrical cond...Molecular doping has become a widely used method to modulate the electric performance of organic semiconductors(OSC).Highly effective charge transfer during molecular doping is desired to achieve ideal electrical conductivity.Two types of charge transfer mechanisms are widely accepted in molecular doping process:integer charge transfer(ICT)and charge transfer complex(CTC).In this review,fundamental principles of two mechanisms are revisited and the characterization methods are depicted.The key points for the formation of two mechanisms are highlighted from aspects of molecular structure and process engineering.Then,the strategies to improve the proportion of ICT are discussed.Finally,the challenges and perspectives for future developments in the molecular doping of polymer semiconductors are provided.展开更多
In this paper, method combined vapor transportation with in-situ chemical reaction is employed to synthesize Cu(TCNQ) nanowires. The typical diameter of nanowires is 50-500 nm with high uniformity. The electrical swit...In this paper, method combined vapor transportation with in-situ chemical reaction is employed to synthesize Cu(TCNQ) nanowires. The typical diameter of nanowires is 50-500 nm with high uniformity. The electrical switching characteristics of single nanowire are observed. The ON-OFF resistance ratio for switching reaches 10~4. The investigation reveals a linear relationship between the switching threshold and the spacing between the two electrodes. The temporal response of the switching process is 30 ns and the switch exhibits good reproducibility. The collapse of the nanowire under the condition of current surge is also discussed. It is believed that the Cu(TCNQ) nanowire could be promising for applications in nanoelectronics.展开更多
The driving voltage of an organic light-emitting diode(OLED) is lowered by employing molybdenum trioxide(MoO3)/N,N'-bis(naphthalene-1-yl)-N,N'-bis(phe-nyl)-benzidine(NPB) multiple quantum well(MQW) struc...The driving voltage of an organic light-emitting diode(OLED) is lowered by employing molybdenum trioxide(MoO3)/N,N'-bis(naphthalene-1-yl)-N,N'-bis(phe-nyl)-benzidine(NPB) multiple quantum well(MQW) structure in the hole transport layer.For the device with double quantum well(DQW) structure of ITO/[MoO3(2.5 nm)/NPB(20 nm)]2/Alq3(50 nm)/LiF(0.8 nm)/Al(120 nm)],the turn-on voltage is reduced to 2.8 V,which is lowered by 0.4 V compared with that of the control device(without MQW structures),and the driving voltage is 5.6 V,which is reduced by 1 V compared with that of the control device at the 1000 cd/m2.In this work,the enhancement of the injection and transport ability for holes could reduce the driving voltage for the device with MQW structure,which is attributed not only to the reduced energy barrier between ITO and NPB,but also to the forming charge transfer complex between MoO3 and NPB induced by the interfacial doping effect of MoO3.展开更多
Electrochemical oxidation of BEDT-TTF (bis (ethylenedithio) tetrathiafulvalene) inchloroform/carbon disulfide (3:1) in the presence of Bu4NBr as a supporting electrolyte at lowcurrent density results in the (BEDT-TTF)...Electrochemical oxidation of BEDT-TTF (bis (ethylenedithio) tetrathiafulvalene) inchloroform/carbon disulfide (3:1) in the presence of Bu4NBr as a supporting electrolyte at lowcurrent density results in the (BEDT-TTF)2Br3H2O crystal. Its composition has been established bychemical analysis (Br, C, H, S), XPS and IR. The temperature dependence of the resistance has beenstudied down to 26K at ambient pressure. This material has weakly metallic behavior above 230K,and becomes a semiconductor below this temperature. The structure of the complex is alsodescribed.展开更多
The dark oxidation reactions of ethers including aether, isopropyl ether, phenyl isopropyl ether, and benzyl isopropyl ether have been studied by using density functional theory calculations. The structures of initial...The dark oxidation reactions of ethers including aether, isopropyl ether, phenyl isopropyl ether, and benzyl isopropyl ether have been studied by using density functional theory calculations. The structures of initial Contact charge transfer complexes (CCTCs), transition states and caged radical intermediates have been located at the B3LYP/6-31G (d) level, The bonding nature of ethers with triplet 02 in CCTCs has been analyzed, and the detailed mechanism of dark oxidation reactions of ether is presented clearly.展开更多
A new spectrophotometric method was developed for the determination of aminomethylbenzoic acid (PAMBA) using 7,7,8,8-tetracyanoquinodimethane (TCNQ). The method was based on the formation of charge transfer (CT)...A new spectrophotometric method was developed for the determination of aminomethylbenzoic acid (PAMBA) using 7,7,8,8-tetracyanoquinodimethane (TCNQ). The method was based on the formation of charge transfer (CT) complex of this drug as n-electron donor with the n-acceptor TCNQ. TCNQ was found to react with PAMBA to produce a kind of yellow complex. The CT reaction proceeded quantitatively in pH 8.5 buffer solution. Different variables affecting the reaction were carefully studied and optimized. Under optimal reaction conditions, the stoichiometric ratio of the reaction, maximum absorption wavelength and the value of molar absorptivity were measured to be 1 : 1, 425 nm, and 1.9 × 10^4 L.mol ^-1.cm^-1, respectively. Beer's law was obeyed in the range of 1- 9 μgomL-1 of PAMBA. The data have been filled to a linear regression equation A= -0.2612+0.1123c (μgomL^-1), with a correlation coefficient of 0.9996. The detection limit was 0.4 μg·mL^-1, R,S.D. was less than 1.9%, and average recovery was over 97.6%. The formation of the CT complex was also confirmed by both infrared and 1H NMR measurements. The thermodynamic property, kinetic property and reaction mechanism have also been discussed. The method developed was applied successfully to the determination of the subject drug in its pharmaceutical dosage forms with good precision and accuracy compared to official method revealed by t- and F-tests.展开更多
Non-aqueous redox flow batteries, because of larger operating voltage, have attracted considerable at- tention for high-density energy storage applications. However, the study of the anolyte is rather limited compared...Non-aqueous redox flow batteries, because of larger operating voltage, have attracted considerable at- tention for high-density energy storage applications. However, the study of the anolyte is rather limited compared with the catholyte due to the labile properties of redox mediators at low potentials. Here, we report a new strategy that exploits high concentration organic lithium metal solution as a robust and energetic anolyte. The solution formed by dissolving metallic lithium with biphenyl (BP) in tetraethylene glycol dimethyl ether (TEGDME) presents a redox potential of 0.39V versus Li/Li+, and a concentration up to 2 M. When coupled with a redox-targeted LiFePO4 catholyte system, the constructed redox flow lithium battery full cell delivers a ceil voltage of 3.0V and presents reasonably good cycling performance.展开更多
The structures and stabilization of three crystal surfaces of TCNQ-based charge transfer complexes(CTCs) including PrQ(TCNQ) 2,MPM(TCNQ) 2,and MEM(TCNQ) 2,have been investigated by scanning tunneling microscop...The structures and stabilization of three crystal surfaces of TCNQ-based charge transfer complexes(CTCs) including PrQ(TCNQ) 2,MPM(TCNQ) 2,and MEM(TCNQ) 2,have been investigated by scanning tunneling microscopy(STM).The three bulk-truncated surfaces are all ac-surface,which are terminated with TCNQ molecular arrays.On the ac-surface of PrQ(TCNQ) 2,the TCNQ molecules form a tetramer structure with a wavelike row behavior and a 纬 angle of about 18掳 between adjacent molecules.Moreover,the dimer structures are resolved on both ac-surfaces of MPM(TCNQ) 2 and MEM(TCNQ) 2.In addition,the tetramer structure is the most stable structure,while the dimer structures are unstable and easily subject to the STM tip disturbance,which results in changeable unit cells.The main reasons for the surface stabilization variation among the three ac-surfaces are provided by using the '蟺-atom model'.展开更多
The improvement of the photocatalytic performance of TiO_(2) nanofibers(NFs),prepared by electrospinning,is achieved by surface modification with the rhodizonic acid(RhA).The condensation reaction between hydroxyl gro...The improvement of the photocatalytic performance of TiO_(2) nanofibers(NFs),prepared by electrospinning,is achieved by surface modification with the rhodizonic acid(RhA).The condensation reaction between hydroxyl groups from TiO_(2) NFs and RhA is accompanied by the red-shift of optical absorption due to interfacial charge transfer(ICT)complex formation.Crystal structure,morphology,and optical properties of unmodified and surface-modified TiO_(2) NFs were analyzed.The photocatalytic performance of prepared samples has been examined through degradation of organic dye methylene blue.Superior photocatalytic activity of surface-modified TiO_(2) NFs with RhA is attributed to their enhanced optical properties,i.e.,the ability to harvest the photon energy in the visible spectral range.展开更多
The kinetics of charge transfer complex(CTC) of 2,3,5,6 tetramethoxyl 1,4 benzoquinone(TMOQ) with two alicyclic N donors,piperidine(PD) and morpholine(ML), in methanol, has been investigated by ultraviolet visible spe...The kinetics of charge transfer complex(CTC) of 2,3,5,6 tetramethoxyl 1,4 benzoquinone(TMOQ) with two alicyclic N donors,piperidine(PD) and morpholine(ML), in methanol, has been investigated by ultraviolet visible spectroscopy. The transformation leads to the formation of substitution products in solution, which have been isolated and characterized as 2,5 diamino 3,6 dimethoxyl 1,4 benzoquinones by 1H NMR, MS, and elemental analysis. The kinetic results of the formation of products indicate that the rate is first order both with the acceptor and the donor. A mechanism of interaction between TMOQ and PD or ML is discussed.展开更多
The interaction of iodine as an cr-acceptor with a synthetic ligand,benzene-1,3-disulfonylamid-kriptofix[22](BDSAK) as a π-donor has been investigated spectrophotometrically in chloroform(CHCl3) and dichlorometh...The interaction of iodine as an cr-acceptor with a synthetic ligand,benzene-1,3-disulfonylamid-kriptofix[22](BDSAK) as a π-donor has been investigated spectrophotometrically in chloroform(CHCl3) and dichloromethane(DCM) solutions.The results of mole ratio plots and Job's method show the stoichiometry of complexation I2/BDSAK is 1:1.Stability constants have been calculated in various temperatures and thermodynamic parameters have also been determined from the temperatures dependence of the stability constants by using van't Hoff equation.The results indicate the iodine complex with BDSAK is enthalpy stabilized but entropy destabilized.展开更多
基金supported by the National Natural Science Foundation of China(No.22001248)the Fundamental Research Funds for the Central Universities and University of Chinese Academy of Sciences.
文摘A charge transfer complex(CTC)-enabled photoreduction of ether phosphonium salts for the generation of oxyalkyl radicals was described.The photoreduction provides a convenient method to achieve selective oxyalkylation of enamides with broad substrate scope.The method features operational simplicity,mild and inherent green conditions.
文摘Two charge-transfer complexes of 2a and 2b of Keggin type were synthesized and characterized by elemental analysis, IR spectra, UV spectra, XRD, TG-DSC; and were compared with Hquin-PW12. The primary structure of the heteropolyanions had not been changed after the formation of the charge transfer complexes.
文摘C<sub>60</sub> is the third form of elementary C, which was discovered in recent years.In C<sub>60</sub>, each C atom links with three adjacent C atoms in terms of sp<sup>2</sup>-like hybridorbitals, in which there are two long bonds and one short bond. At present, sincemacro-quantity of C<sub>60</sub> is able to be produced with simple method, interest instudy on C<sub>60</sub> shifts to its chemical properties from the structure. (P(C<sub>6</sub>H<sub>5</sub>)<sub>3</sub>)<sub>2</sub>Ptand C<sub>60</sub> themselves are stable valence-saturated molecules, however, they can form sta-ble complexes through the charge transfer, in which (P(C<sub>6</sub>H<sub>5</sub>)<sub>3</sub>)<sub>2</sub> Pt is complexed
基金the National Natural Science Foundation of China (No. 92263109)the Shanghai Rising-Star Program (No. 22QA1410400)Natural Science Foundation of Shanghai (No. 23ZR1472200).
文摘Molecular doping has become a widely used method to modulate the electric performance of organic semiconductors(OSC).Highly effective charge transfer during molecular doping is desired to achieve ideal electrical conductivity.Two types of charge transfer mechanisms are widely accepted in molecular doping process:integer charge transfer(ICT)and charge transfer complex(CTC).In this review,fundamental principles of two mechanisms are revisited and the characterization methods are depicted.The key points for the formation of two mechanisms are highlighted from aspects of molecular structure and process engineering.Then,the strategies to improve the proportion of ICT are discussed.Finally,the challenges and perspectives for future developments in the molecular doping of polymer semiconductors are provided.
基金financial support from Shanghai Science and Technology Development Fund(No.0752nm016)Shanghai Leading Academic Development Project(No.B113)
文摘In this paper, method combined vapor transportation with in-situ chemical reaction is employed to synthesize Cu(TCNQ) nanowires. The typical diameter of nanowires is 50-500 nm with high uniformity. The electrical switching characteristics of single nanowire are observed. The ON-OFF resistance ratio for switching reaches 10~4. The investigation reveals a linear relationship between the switching threshold and the spacing between the two electrodes. The temporal response of the switching process is 30 ns and the switch exhibits good reproducibility. The collapse of the nanowire under the condition of current surge is also discussed. It is believed that the Cu(TCNQ) nanowire could be promising for applications in nanoelectronics.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 60906022 and 60676051)the Natural Science Foundation of Tianjin,China (Grant No. 10JCYBJC01100)+1 种基金the Scientific Developing Foundation of Tianjin Education Commission,China (Grant No. 2011ZD02)the Jiangsu Natural Science Development Foundation for University,China (Grant No. 09KJB140006)
文摘The driving voltage of an organic light-emitting diode(OLED) is lowered by employing molybdenum trioxide(MoO3)/N,N'-bis(naphthalene-1-yl)-N,N'-bis(phe-nyl)-benzidine(NPB) multiple quantum well(MQW) structure in the hole transport layer.For the device with double quantum well(DQW) structure of ITO/[MoO3(2.5 nm)/NPB(20 nm)]2/Alq3(50 nm)/LiF(0.8 nm)/Al(120 nm)],the turn-on voltage is reduced to 2.8 V,which is lowered by 0.4 V compared with that of the control device(without MQW structures),and the driving voltage is 5.6 V,which is reduced by 1 V compared with that of the control device at the 1000 cd/m2.In this work,the enhancement of the injection and transport ability for holes could reduce the driving voltage for the device with MQW structure,which is attributed not only to the reduced energy barrier between ITO and NPB,but also to the forming charge transfer complex between MoO3 and NPB induced by the interfacial doping effect of MoO3.
文摘Electrochemical oxidation of BEDT-TTF (bis (ethylenedithio) tetrathiafulvalene) inchloroform/carbon disulfide (3:1) in the presence of Bu4NBr as a supporting electrolyte at lowcurrent density results in the (BEDT-TTF)2Br3H2O crystal. Its composition has been established bychemical analysis (Br, C, H, S), XPS and IR. The temperature dependence of the resistance has beenstudied down to 26K at ambient pressure. This material has weakly metallic behavior above 230K,and becomes a semiconductor below this temperature. The structure of the complex is alsodescribed.
基金Project supported by the National Natural Science Foundation of China (No. 20473047) and the Major State Basic Research Development Program of China (973 Program, No. 2004CB719902)
文摘The dark oxidation reactions of ethers including aether, isopropyl ether, phenyl isopropyl ether, and benzyl isopropyl ether have been studied by using density functional theory calculations. The structures of initial Contact charge transfer complexes (CCTCs), transition states and caged radical intermediates have been located at the B3LYP/6-31G (d) level, The bonding nature of ethers with triplet 02 in CCTCs has been analyzed, and the detailed mechanism of dark oxidation reactions of ether is presented clearly.
基金Project supported by the National Natural Science Foundation of China (No. 21076138) and the Natural Science Foundation of Shanxi Institution of Higher Education (No. 20080025).
文摘A new spectrophotometric method was developed for the determination of aminomethylbenzoic acid (PAMBA) using 7,7,8,8-tetracyanoquinodimethane (TCNQ). The method was based on the formation of charge transfer (CT) complex of this drug as n-electron donor with the n-acceptor TCNQ. TCNQ was found to react with PAMBA to produce a kind of yellow complex. The CT reaction proceeded quantitatively in pH 8.5 buffer solution. Different variables affecting the reaction were carefully studied and optimized. Under optimal reaction conditions, the stoichiometric ratio of the reaction, maximum absorption wavelength and the value of molar absorptivity were measured to be 1 : 1, 425 nm, and 1.9 × 10^4 L.mol ^-1.cm^-1, respectively. Beer's law was obeyed in the range of 1- 9 μgomL-1 of PAMBA. The data have been filled to a linear regression equation A= -0.2612+0.1123c (μgomL^-1), with a correlation coefficient of 0.9996. The detection limit was 0.4 μg·mL^-1, R,S.D. was less than 1.9%, and average recovery was over 97.6%. The formation of the CT complex was also confirmed by both infrared and 1H NMR measurements. The thermodynamic property, kinetic property and reaction mechanism have also been discussed. The method developed was applied successfully to the determination of the subject drug in its pharmaceutical dosage forms with good precision and accuracy compared to official method revealed by t- and F-tests.
基金financial support by the Energy Market Authority, Singapore under its Energy Innovation Research Programme-Energy Storage (NRF2015EWT-EIRP002)
文摘Non-aqueous redox flow batteries, because of larger operating voltage, have attracted considerable at- tention for high-density energy storage applications. However, the study of the anolyte is rather limited compared with the catholyte due to the labile properties of redox mediators at low potentials. Here, we report a new strategy that exploits high concentration organic lithium metal solution as a robust and energetic anolyte. The solution formed by dissolving metallic lithium with biphenyl (BP) in tetraethylene glycol dimethyl ether (TEGDME) presents a redox potential of 0.39V versus Li/Li+, and a concentration up to 2 M. When coupled with a redox-targeted LiFePO4 catholyte system, the constructed redox flow lithium battery full cell delivers a ceil voltage of 3.0V and presents reasonably good cycling performance.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.10804010,50772015,60977015,and 10974019)the National Basic Research Program of China(Grant No.2006CB932301)the Scientific Research Foundation for the Returned Overseas Chinese Scholars of Ministry of Education
文摘The structures and stabilization of three crystal surfaces of TCNQ-based charge transfer complexes(CTCs) including PrQ(TCNQ) 2,MPM(TCNQ) 2,and MEM(TCNQ) 2,have been investigated by scanning tunneling microscopy(STM).The three bulk-truncated surfaces are all ac-surface,which are terminated with TCNQ molecular arrays.On the ac-surface of PrQ(TCNQ) 2,the TCNQ molecules form a tetramer structure with a wavelike row behavior and a 纬 angle of about 18掳 between adjacent molecules.Moreover,the dimer structures are resolved on both ac-surfaces of MPM(TCNQ) 2 and MEM(TCNQ) 2.In addition,the tetramer structure is the most stable structure,while the dimer structures are unstable and easily subject to the STM tip disturbance,which results in changeable unit cells.The main reasons for the surface stabilization variation among the three ac-surfaces are provided by using the '蟺-atom model'.
基金The authors thank the National Key Research and Development Program of China(2016YFA0201702/2016YFA0201700)the Shanghai Natural Science Foundation(19ZR1400900)+3 种基金the Science and Technology Commission of Shanghai Municipality(16JC1400700)the Fundamental Research Funds for the Central Universities(Grant No.2232018A3-01)the Program for Innovative Research Team at the University of Ministry of Education of China(IRT_16R13)the International Joint Laboratory for Advanced Fiber and Low-dimension Materials(18520750400).
文摘The improvement of the photocatalytic performance of TiO_(2) nanofibers(NFs),prepared by electrospinning,is achieved by surface modification with the rhodizonic acid(RhA).The condensation reaction between hydroxyl groups from TiO_(2) NFs and RhA is accompanied by the red-shift of optical absorption due to interfacial charge transfer(ICT)complex formation.Crystal structure,morphology,and optical properties of unmodified and surface-modified TiO_(2) NFs were analyzed.The photocatalytic performance of prepared samples has been examined through degradation of organic dye methylene blue.Superior photocatalytic activity of surface-modified TiO_(2) NFs with RhA is attributed to their enhanced optical properties,i.e.,the ability to harvest the photon energy in the visible spectral range.
文摘The kinetics of charge transfer complex(CTC) of 2,3,5,6 tetramethoxyl 1,4 benzoquinone(TMOQ) with two alicyclic N donors,piperidine(PD) and morpholine(ML), in methanol, has been investigated by ultraviolet visible spectroscopy. The transformation leads to the formation of substitution products in solution, which have been isolated and characterized as 2,5 diamino 3,6 dimethoxyl 1,4 benzoquinones by 1H NMR, MS, and elemental analysis. The kinetic results of the formation of products indicate that the rate is first order both with the acceptor and the donor. A mechanism of interaction between TMOQ and PD or ML is discussed.
文摘The interaction of iodine as an cr-acceptor with a synthetic ligand,benzene-1,3-disulfonylamid-kriptofix[22](BDSAK) as a π-donor has been investigated spectrophotometrically in chloroform(CHCl3) and dichloromethane(DCM) solutions.The results of mole ratio plots and Job's method show the stoichiometry of complexation I2/BDSAK is 1:1.Stability constants have been calculated in various temperatures and thermodynamic parameters have also been determined from the temperatures dependence of the stability constants by using van't Hoff equation.The results indicate the iodine complex with BDSAK is enthalpy stabilized but entropy destabilized.