Zn_（0.8）Cd_（0.2）O thin films prepared using the spin-coating method were investigated. X-ray diffraction, scanning electron microscopy, and UV-Vis spectrophotometry were employed to illustrate the effects of the p...Zn_（0.8）Cd_（0.2）O thin films prepared using the spin-coating method were investigated. X-ray diffraction, scanning electron microscopy, and UV-Vis spectrophotometry were employed to illustrate the effects of the pre-heating temperature on the crystalline structure, surface morphology and transmission spectra of Zn_（0.8）Cd_（0.2）O thin films. When the thin films were pre-heated at 150 ℃, polycrystalline Zn O thin films were obtained. When the thin films were pre-heated at temperatures of 200 ℃ or higher, preferential growth of Zn O nanocrystals along the c-axis was observed. Transmission spectra showed that thin films with high transmission in the visible light range were prepared and effective bandgap energies of these thin films decreased from 3.19 e V to 3.08 e V when the pre-heating temperature increased from 150 ℃ to 300 ℃.展开更多
We present structural,magnetic and optical characteristics of Zn_（1-x）TM_xTe（TM = Mn,Fe,Co,Ni and x = 6.25%）,calculated through Wien2 k code,by using full potential linearized augmented plane wave（FP-LAPW） techn...We present structural,magnetic and optical characteristics of Zn_（1-x）TM_xTe（TM = Mn,Fe,Co,Ni and x = 6.25%）,calculated through Wien2 k code,by using full potential linearized augmented plane wave（FP-LAPW） technique.The optimization of the crystal structures have been done to compare the ferromagnetic（FM） and antiferromagnetic（AFM） ground state energies,to elucidate the ferromagnetic phase stability,which further has been verified through the formation and cohesive energies.Moreover,the estimated Curie temperatures T_c have demonstrated above room temperature ferromagnetism（RTFM） in Zn_（1-x）TM_xTe（TM =Mn,Fe,Co,Ni and x= 6.25%）.The calculated electronic properties have depicted that Mn- and Co-doped ZnTe behave as ferromagnetic semiconductors,while half-metallic ferromagnetic behaviors are observed in Fe- and Ni-doped ZnTe.The presence of ferromagnetism is also demonstrated to be due to both the p-d and s-d hybridizations between the host lattice cations and TM impurities.The calculated band gaps and static real dielectric constants have been observed to vary according to Penn＇s model.The evaluated band gaps lie in near visible and ultraviolet regions,which make these materials suitable for various important device applications in optoelectronic and spintronic.展开更多
By the additional reaction of binuclear compounds (Me4N)2M2S4 (TDT)2 (M = Mo, W; H2TDT= H2CH3GH3S2) with mononuclear cuprous complex, two new M-Cu-S clusters Mo2 Cu2 S4 (TDT)2-(PPh3)2CH3CH2OH (1) and W2Cu2S4 (TDT)2 (P...By the additional reaction of binuclear compounds (Me4N)2M2S4 (TDT)2 (M = Mo, W; H2TDT= H2CH3GH3S2) with mononuclear cuprous complex, two new M-Cu-S clusters Mo2 Cu2 S4 (TDT)2-(PPh3)2CH3CH2OH (1) and W2Cu2S4 (TDT)2 (PPh3 )2 · 0. 5CH3 CH2 OH·0. 5H2O (2) have been prepared and characterized by IR, UV-Vis, 31P NMR spectroscopy, cyclic voltammetry and single crystal X-ray structure analysis. Both compounds crystallize in space group P 21/ n with lattice parameters a = 1.0956(3), b = 2. 2072(3), c =2.4340(3) nm, β=100.36(2)°, V= 5.790(3) nm3 and Z = 4 for 1 and a = 1.0965(9), b = 2.2135(3), c = 2.4317(4) nm, β = 99. 63(8)°, V = 5.819(8) nm3 and Z = 4 for 2. Both molecular structures contain a cubane-like cluster core [M2Cu2S4] (M= Mo, W) and their skeletons are almost the same except for M atoms. The syntheses, structures and spectrum characterizations of these two clusters are discussed. The third-order nonlinear optical (NLO) property of the two clusters was studied by the technique of forward degenerate four-wave mixing (DFWM) for the first time and these clusters exhibited relatively large nonlinear optical coefficients.展开更多
Reaction of [PPh_4][(η 5-C_5Me_5)WS_3] with CuI,CuBr and bis^(diphenylphosphino)methane (dppm) (molar ratio=1∶2∶1∶1) in MeCN gave rise to [PPh_4][(η 5-C_5Me_5)WS_3(CuBr)(CuI)_2-(μ-dppm)] (1) in high yield. Com...Reaction of [PPh_4][(η 5-C_5Me_5)WS_3] with CuI,CuBr and bis^(diphenylphosphino)methane (dppm) (molar ratio=1∶2∶1∶1) in MeCN gave rise to [PPh_4][(η 5-C_5Me_5)WS_3(CuBr)(CuI)_2-(μ-dppm)] (1) in high yield. Compound 1 crystallizes in the monoclinic,space group P2_1/n with lattice parameters:a=1.2906(4) nm, b=1.5006(8) nm,c=3.1484(6) nm,β= 92.12(2)°,V=6.093(3) nm 3,Z=4. The structure of the anion of 1 contains an incomplete WS_3Cu_3 cubane-like core in which two CuI units are bridged by a dppm ligand. The W—Cu distances vary in the range of 0.2644(1)—0.2793(1) nm. The optical limiting (OL) properties of 1 in MeCN were measured with the laser pulse-width of 12-ns at 532 nm,and the nanosecond OL effect may be due to the reverse saturable absorption (RSA) related to the excited triplet states.展开更多
The structural, electronic, and optical absorption properties of TiO2 nanotube （TiO2NT） with Cun clusters （n =1-4） adsorbed on its surface have been investigated based on density functional theory calculations. Th...The structural, electronic, and optical absorption properties of TiO2 nanotube （TiO2NT） with Cun clusters （n =1-4） adsorbed on its surface have been investigated based on density functional theory calculations. The TiO2NT is constructed by rolling up a （101） sheet of anatase TiO2 around the [ 1-01 ] direction; the ground states of Cun/TiOzNT systems are determined by analyzing the average adsorption energies. Calculation results show that odd-even oscillations occur for the average adsorption energy, the Cu-O bond length, and the amount of transferred electrons, with the increase in Cu. cluster size; and the Cun/TiO2NTs with odd n＇s demonstrate stronger interaction between the Cu. cluster and the TiO2NT. Also, the impurity states introduced by the Cun cluster to the band gap of TiOzNT cause an obvious redshift of the optical absorption spectrum toward the visible light region, especially for the even n cases.展开更多
利用射频磁控溅射法在玻璃衬底上制备SnS薄膜,用X射线衍射(XRD)、能谱仪(EDS)、原子力显微镜(AFM)、场发射扫描电镜(FE-SEM)和紫外-可见-近红外分光光度计(UV-Vis-NIR)分别对所制备的薄膜晶体结构、组分、表面形貌、厚度、反射率和透过...利用射频磁控溅射法在玻璃衬底上制备SnS薄膜,用X射线衍射(XRD)、能谱仪(EDS)、原子力显微镜(AFM)、场发射扫描电镜(FE-SEM)和紫外-可见-近红外分光光度计(UV-Vis-NIR)分别对所制备的薄膜晶体结构、组分、表面形貌、厚度、反射率和透过率进行表征分析。研究结果表明:薄膜厚度的增加有利于改善薄膜的结晶质量和组分配比,晶粒尺寸和颗粒尺寸随着厚度的增加而变大。样品的折射率在1 500~2 500nm波长范围内随着薄膜厚度的增加而增大。样品在可见光区域吸收强烈,吸收系数达105cm-1量级。禁带宽度在薄膜厚度增加到1 042 nm时为1.57 e V,接近于太阳电池材料的的最佳光学带隙(1.5 e V)。展开更多
The title cluster compound [WS4Cu3Br(bipy)2] has been synthesized by the reaction of (NH4)2, CuBr and 2,2′ bipy in DMF solution. Single crystal X ray diffraction data show that the compound has a nest shaped structur...The title cluster compound [WS4Cu3Br(bipy)2] has been synthesized by the reaction of (NH4)2, CuBr and 2,2′ bipy in DMF solution. Single crystal X ray diffraction data show that the compound has a nest shaped structure. Nonlinear optical properties (NLO) of the cluster were investigated by a Z scan technique with a pulsed laser at 532nm. The cluster exhibits the strong NLO absorption and a self defocusing effect (effective non linear absorption coefficient, α2eff=7.3×10-11mW-1; effective non linear refractive index, n2eff=3.9×10-11esu) when measured in a 6.0×10-4mol·dm-3 DMF solution. CCDC: 200397.展开更多
基金Funded by the National Natural Science Foundation of China(No.51461135004)the Doctoral Fund of Ministry of Education Priority Development Project(No.20130143130002)+1 种基金the Key Technology Innovation Project of Hubei Province(2013AAA005)the Scientific Leadership training Program of Hubei Province
文摘Zn_（0.8）Cd_（0.2）O thin films prepared using the spin-coating method were investigated. X-ray diffraction, scanning electron microscopy, and UV-Vis spectrophotometry were employed to illustrate the effects of the pre-heating temperature on the crystalline structure, surface morphology and transmission spectra of Zn_（0.8）Cd_（0.2）O thin films. When the thin films were pre-heated at 150 ℃, polycrystalline Zn O thin films were obtained. When the thin films were pre-heated at temperatures of 200 ℃ or higher, preferential growth of Zn O nanocrystals along the c-axis was observed. Transmission spectra showed that thin films with high transmission in the visible light range were prepared and effective bandgap energies of these thin films decreased from 3.19 e V to 3.08 e V when the pre-heating temperature increased from 150 ℃ to 300 ℃.
基金the University of the Punjab, Lahore for financial support through faculty research grant program
文摘We present structural,magnetic and optical characteristics of Zn_（1-x）TM_xTe（TM = Mn,Fe,Co,Ni and x = 6.25%）,calculated through Wien2 k code,by using full potential linearized augmented plane wave（FP-LAPW） technique.The optimization of the crystal structures have been done to compare the ferromagnetic（FM） and antiferromagnetic（AFM） ground state energies,to elucidate the ferromagnetic phase stability,which further has been verified through the formation and cohesive energies.Moreover,the estimated Curie temperatures T_c have demonstrated above room temperature ferromagnetism（RTFM） in Zn_（1-x）TM_xTe（TM =Mn,Fe,Co,Ni and x= 6.25%）.The calculated electronic properties have depicted that Mn- and Co-doped ZnTe behave as ferromagnetic semiconductors,while half-metallic ferromagnetic behaviors are observed in Fe- and Ni-doped ZnTe.The presence of ferromagnetism is also demonstrated to be due to both the p-d and s-d hybridizations between the host lattice cations and TM impurities.The calculated band gaps and static real dielectric constants have been observed to vary according to Penn＇s model.The evaluated band gaps lie in near visible and ultraviolet regions,which make these materials suitable for various important device applications in optoelectronic and spintronic.
基金Project (No.29733090 and 29673046) supported by the National Natural Science Foundation of Chinathe Natural Science Foundation of Fujian Province,the Foundation of State Key Laboratory of Structural Chemistry.
文摘By the additional reaction of binuclear compounds (Me4N)2M2S4 (TDT)2 (M = Mo, W; H2TDT= H2CH3GH3S2) with mononuclear cuprous complex, two new M-Cu-S clusters Mo2 Cu2 S4 (TDT)2-(PPh3)2CH3CH2OH (1) and W2Cu2S4 (TDT)2 (PPh3 )2 · 0. 5CH3 CH2 OH·0. 5H2O (2) have been prepared and characterized by IR, UV-Vis, 31P NMR spectroscopy, cyclic voltammetry and single crystal X-ray structure analysis. Both compounds crystallize in space group P 21/ n with lattice parameters a = 1.0956(3), b = 2. 2072(3), c =2.4340(3) nm, β=100.36(2)°, V= 5.790(3) nm3 and Z = 4 for 1 and a = 1.0965(9), b = 2.2135(3), c = 2.4317(4) nm, β = 99. 63(8)°, V = 5.819(8) nm3 and Z = 4 for 2. Both molecular structures contain a cubane-like cluster core [M2Cu2S4] (M= Mo, W) and their skeletons are almost the same except for M atoms. The syntheses, structures and spectrum characterizations of these two clusters are discussed. The third-order nonlinear optical (NLO) property of the two clusters was studied by the technique of forward degenerate four-wave mixing (DFWM) for the first time and these clusters exhibited relatively large nonlinear optical coefficients.
基金ProjectsupportedbytheNationalNaturalScienceFoundationofChina (No .2 0 2 710 3 6) ,theNaturalScienceFoundationoftheEducationCommitteeofJiangsuProvince (No .0 2KJB15 0 0 0 1) ,StateKeyLabofCoordinationChemistryofNanjingUniversity ,andtheScientificResearchF
文摘Reaction of [PPh_4][(η 5-C_5Me_5)WS_3] with CuI,CuBr and bis^(diphenylphosphino)methane (dppm) (molar ratio=1∶2∶1∶1) in MeCN gave rise to [PPh_4][(η 5-C_5Me_5)WS_3(CuBr)(CuI)_2-(μ-dppm)] (1) in high yield. Compound 1 crystallizes in the monoclinic,space group P2_1/n with lattice parameters:a=1.2906(4) nm, b=1.5006(8) nm,c=3.1484(6) nm,β= 92.12(2)°,V=6.093(3) nm 3,Z=4. The structure of the anion of 1 contains an incomplete WS_3Cu_3 cubane-like core in which two CuI units are bridged by a dppm ligand. The W—Cu distances vary in the range of 0.2644(1)—0.2793(1) nm. The optical limiting (OL) properties of 1 in MeCN were measured with the laser pulse-width of 12-ns at 532 nm,and the nanosecond OL effect may be due to the reverse saturable absorption (RSA) related to the excited triplet states.
基金supported by the National Natural Science Foundation of China(Grant No.11104199)the Natural Science Foundation of Shanxi Province,China(Grant No.2012011021-3)
文摘The structural, electronic, and optical absorption properties of TiO2 nanotube （TiO2NT） with Cun clusters （n =1-4） adsorbed on its surface have been investigated based on density functional theory calculations. The TiO2NT is constructed by rolling up a （101） sheet of anatase TiO2 around the [ 1-01 ] direction; the ground states of Cun/TiOzNT systems are determined by analyzing the average adsorption energies. Calculation results show that odd-even oscillations occur for the average adsorption energy, the Cu-O bond length, and the amount of transferred electrons, with the increase in Cu. cluster size; and the Cun/TiO2NTs with odd n＇s demonstrate stronger interaction between the Cu. cluster and the TiO2NT. Also, the impurity states introduced by the Cun cluster to the band gap of TiOzNT cause an obvious redshift of the optical absorption spectrum toward the visible light region, especially for the even n cases.
文摘利用射频磁控溅射法在玻璃衬底上制备SnS薄膜,用X射线衍射(XRD)、能谱仪(EDS)、原子力显微镜(AFM)、场发射扫描电镜(FE-SEM)和紫外-可见-近红外分光光度计(UV-Vis-NIR)分别对所制备的薄膜晶体结构、组分、表面形貌、厚度、反射率和透过率进行表征分析。研究结果表明:薄膜厚度的增加有利于改善薄膜的结晶质量和组分配比,晶粒尺寸和颗粒尺寸随着厚度的增加而变大。样品的折射率在1 500~2 500nm波长范围内随着薄膜厚度的增加而增大。样品在可见光区域吸收强烈,吸收系数达105cm-1量级。禁带宽度在薄膜厚度增加到1 042 nm时为1.57 e V,接近于太阳电池材料的的最佳光学带隙(1.5 e V)。
文摘The title cluster compound [WS4Cu3Br(bipy)2] has been synthesized by the reaction of (NH4)2, CuBr and 2,2′ bipy in DMF solution. Single crystal X ray diffraction data show that the compound has a nest shaped structure. Nonlinear optical properties (NLO) of the cluster were investigated by a Z scan technique with a pulsed laser at 532nm. The cluster exhibits the strong NLO absorption and a self defocusing effect (effective non linear absorption coefficient, α2eff=7.3×10-11mW-1; effective non linear refractive index, n2eff=3.9×10-11esu) when measured in a 6.0×10-4mol·dm-3 DMF solution. CCDC: 200397.
