The detailed theoretical studies of electronic,optical,and mechanical properties of γ-Bi2Sn2O7 are carried out by using first-principle density functional theory calculations.Our calculated results indicate that γ-B...The detailed theoretical studies of electronic,optical,and mechanical properties of γ-Bi2Sn2O7 are carried out by using first-principle density functional theory calculations.Our calculated results indicate that γ-Bi2Sn2O7 is the p-type semiconductor with an indirect band gap of about 2.72 e V.The flat electronic bands close to the valence band maximum are mainly composed of Bi-6s and O-2p states and play a key role in determining the electrical properties of γ-Bi2Sn2O7.The calculated complex dielectric function and macroscopic optical constants including refractive index,extinction coefficient,absorption coefficients,reflectivity,and electron energy-loss function show that γ-Bi2Sn2O7 is an excellent light absorbing material.The analysis on mechanical properties shows that γ-Bi2Sn2O7 is mechanically stable and highly isotropic.展开更多
A new chiral multidenate ligand (S, S)-1,7-bis(4-benzyloxazolin-2-yl-methyl)-1, 7-diaza- 12-crown-4 1 has been synthesized and used as ligand in the copper catalyzed asymmetric cyclopropanation of 1, 1-diphenylethylene.
The assembling of a coating of time-resolved fluorescent chelator BSPDA ( abbreviated for 4, 7-bis ( sulfhydrylphenyl)-1, 10-phenanthroline-2, 9-dicarboxylic acid) onto a nano-gold layer was demonstrated. First, B...The assembling of a coating of time-resolved fluorescent chelator BSPDA ( abbreviated for 4, 7-bis ( sulfhydrylphenyl)-1, 10-phenanthroline-2, 9-dicarboxylic acid) onto a nano-gold layer was demonstrated. First, BSPDA was synthesized by simple procedures, and then an approach was developed to immobilize BSPDA onto the nano-gold layer deposited on a silane modified glass substrate, whereby europium ion (Ⅲ, Eu^3+ ) was captured and released owing to the interactive process of complexation and dissociation between BSPDA functionalized coating and Eu^3+ solution. The fluorescence spectra and related lifetimes were determined. Also, the BSPDA functionalized coating's specific complexation with Eu^3+ on the BSPDA assembly layer and the nonspecific adsorption of Eu^3+ on the nano-gold layer were compared. These results allowed a selective complexation of Eu^3+ by assembling a BSPDA chelating layer on the nano-gold layer; thus, a tunable time-resolved fluorescent layer was covalently attached, The results of the nanoparticle assembling and probing (or labeling) processes to specific bio-systems were very interesting and had significant implications to time-resolved-fluorescence-based detection on biosensor surfaces such as DNA chip and to arrayed light display devices.展开更多
To increase the current density of the hole only device, 1, 4, 5, 8, 9, 11-hexaazatriphenylene-hexacarbonitrile (HAT-CN) material has been inserted in the device at the indium tin oxide (ITO)/organic interface. Since ...To increase the current density of the hole only device, 1, 4, 5, 8, 9, 11-hexaazatriphenylene-hexacarbonitrile (HAT-CN) material has been inserted in the device at the indium tin oxide (ITO)/organic interface. Since HATCN molecule can withdraw electrons, it can alter electronic properties of the electrodes and hence inserted between the organic/metal interfaces. This paper deals with the optimization of the thickness of organic-metal layers to enhance the efficiency. Also, efforts have been made to increase the current density and reduce the operating voltage of the device. The material 2, 7-bis [N, N-bis (4- methoxy-phenyl) amino]-9, 9-spirobifluorene (Meo-Spiro-TPD) is used to simulate the hole only device because it is a thermally stable hole transport material. Simulated results shows that better current density values can be achieved compared to fabricated one by optimizing the organic metal layer thickness. The best optimized layer thickness of 22 nm for Alq3, 25 nm for *CBP doped with Ir(ppy)3, 9 nm for Meo-Spiro TPD and 4 nm for HAT-CN which results in current density of 0.12 A/cm2 with a reduction in operating voltage by approximately 2 V.展开更多
In this paper,two compounds[Zn_(2)^(2+)(2,6-bis(4΄-pyridyl)-TTF)(TPA)_(2)^(2-)](1)and[Cd^(2+)(2,6(7)-bis(4΄-pyridyl)-TTF)(TPA)2-(H_(2)O)_(2)](TTF=tetrathiafulvalene,TPA=terephthalic acid)(2)were synthesized by using s...In this paper,two compounds[Zn_(2)^(2+)(2,6-bis(4΄-pyridyl)-TTF)(TPA)_(2)^(2-)](1)and[Cd^(2+)(2,6(7)-bis(4΄-pyridyl)-TTF)(TPA)2-(H_(2)O)_(2)](TTF=tetrathiafulvalene,TPA=terephthalic acid)(2)were synthesized by using solvothermal method and characterized by single-crystal X-ray.The purity of the two compounds was confirmed by their PXRD data.We also tested the photocurrent responses of these two compounds,and found they could generate photocurrent signal when exposed to light,but the photocurrent intensity of compound 2 is significantly greater than that of 1.From the crystal structure analysis,the possible reason for this phenomenon is that 2 has a more compact ligand arrangement than 1,leading to a higher carrier density and easier excitation.展开更多
基金Project supported by the National Basic Research Program of China(Grant No.2014CB643703)the National Natural Science Foundation of China(Grant Nos.11164005,11464008,and 51401060)+1 种基金the Natural Science Foundation of Guangxi Zhuang Autonomous Region,China(Grant Nos.2014GXNSFGA118001 and 2012GXNSFGA060002)the Fund from Guangxi Provincial Key Laboratory of Information Materials of Guangxi Zhuang Autonomous Region,China(Grant Nos.1210908-215-Z and 131022-Z)
文摘The detailed theoretical studies of electronic,optical,and mechanical properties of γ-Bi2Sn2O7 are carried out by using first-principle density functional theory calculations.Our calculated results indicate that γ-Bi2Sn2O7 is the p-type semiconductor with an indirect band gap of about 2.72 e V.The flat electronic bands close to the valence band maximum are mainly composed of Bi-6s and O-2p states and play a key role in determining the electrical properties of γ-Bi2Sn2O7.The calculated complex dielectric function and macroscopic optical constants including refractive index,extinction coefficient,absorption coefficients,reflectivity,and electron energy-loss function show that γ-Bi2Sn2O7 is an excellent light absorbing material.The analysis on mechanical properties shows that γ-Bi2Sn2O7 is mechanically stable and highly isotropic.
文摘A new chiral multidenate ligand (S, S)-1,7-bis(4-benzyloxazolin-2-yl-methyl)-1, 7-diaza- 12-crown-4 1 has been synthesized and used as ligand in the copper catalyzed asymmetric cyclopropanation of 1, 1-diphenylethylene.
基金Project supported by the National Natural Science Foundation of China (20505020) the Natural Science Foundation ofGuangdong Province (06300086) +2 种基金 China Postdoctoral Science Foundation (20060390202) Scientific Research Fund ofHunan Provincial Education Department (05C508) Skeleton Youth Faculty Programof Hunan Higher Educational School
文摘The assembling of a coating of time-resolved fluorescent chelator BSPDA ( abbreviated for 4, 7-bis ( sulfhydrylphenyl)-1, 10-phenanthroline-2, 9-dicarboxylic acid) onto a nano-gold layer was demonstrated. First, BSPDA was synthesized by simple procedures, and then an approach was developed to immobilize BSPDA onto the nano-gold layer deposited on a silane modified glass substrate, whereby europium ion (Ⅲ, Eu^3+ ) was captured and released owing to the interactive process of complexation and dissociation between BSPDA functionalized coating and Eu^3+ solution. The fluorescence spectra and related lifetimes were determined. Also, the BSPDA functionalized coating's specific complexation with Eu^3+ on the BSPDA assembly layer and the nonspecific adsorption of Eu^3+ on the nano-gold layer were compared. These results allowed a selective complexation of Eu^3+ by assembling a BSPDA chelating layer on the nano-gold layer; thus, a tunable time-resolved fluorescent layer was covalently attached, The results of the nanoparticle assembling and probing (or labeling) processes to specific bio-systems were very interesting and had significant implications to time-resolved-fluorescence-based detection on biosensor surfaces such as DNA chip and to arrayed light display devices.
文摘To increase the current density of the hole only device, 1, 4, 5, 8, 9, 11-hexaazatriphenylene-hexacarbonitrile (HAT-CN) material has been inserted in the device at the indium tin oxide (ITO)/organic interface. Since HATCN molecule can withdraw electrons, it can alter electronic properties of the electrodes and hence inserted between the organic/metal interfaces. This paper deals with the optimization of the thickness of organic-metal layers to enhance the efficiency. Also, efforts have been made to increase the current density and reduce the operating voltage of the device. The material 2, 7-bis [N, N-bis (4- methoxy-phenyl) amino]-9, 9-spirobifluorene (Meo-Spiro-TPD) is used to simulate the hole only device because it is a thermally stable hole transport material. Simulated results shows that better current density values can be achieved compared to fabricated one by optimizing the organic metal layer thickness. The best optimized layer thickness of 22 nm for Alq3, 25 nm for *CBP doped with Ir(ppy)3, 9 nm for Meo-Spiro TPD and 4 nm for HAT-CN which results in current density of 0.12 A/cm2 with a reduction in operating voltage by approximately 2 V.
基金the Natural Science Foundation of Zhejiang Province(LY18B020016)Ningbo Science and Technology Innovation 2025(2018B10033)。
文摘In this paper,two compounds[Zn_(2)^(2+)(2,6-bis(4΄-pyridyl)-TTF)(TPA)_(2)^(2-)](1)and[Cd^(2+)(2,6(7)-bis(4΄-pyridyl)-TTF)(TPA)2-(H_(2)O)_(2)](TTF=tetrathiafulvalene,TPA=terephthalic acid)(2)were synthesized by using solvothermal method and characterized by single-crystal X-ray.The purity of the two compounds was confirmed by their PXRD data.We also tested the photocurrent responses of these two compounds,and found they could generate photocurrent signal when exposed to light,but the photocurrent intensity of compound 2 is significantly greater than that of 1.From the crystal structure analysis,the possible reason for this phenomenon is that 2 has a more compact ligand arrangement than 1,leading to a higher carrier density and easier excitation.