TiO2 is a wide band gap semiconductor with important applications in photovoltaic cells. Vertically aligned Tit2 nanorod arrays （NRs） are grown on the fluorine-doped tin oxide （FTO） substrates by a multicycle hydr...TiO2 is a wide band gap semiconductor with important applications in photovoltaic cells. Vertically aligned Tit2 nanorod arrays （NRs） are grown on the fluorine-doped tin oxide （FTO） substrates by a multicycle hydrothermal synthesis process. The samples are characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, high-resolution transmission electron microscopy （HRTEM）, and selected-area electron diffraction （SAED）. It is found that dye-sensitized solar cells （DSSCs） assembled by the as-prepared Tit2 single-crystal NRs exhibit different trends under the condition of different nucleation and growth concentrations. Optimum cell performance is obtained with high nucleation concentration and low growth cycle concentration. The efficiency enhancement is mainly attributed to the improved specific surface area of the nanorod.展开更多
A new compound,[Co（dien）2]（dienH3）（H3O）7[P2Mo5O23]2·14H2O, has been hydrothermallly synthesized by using Na2MoO4,CoCl2, H3PO4 and dien, and structurally characterized by elemental analysis, X-ray powder dif...A new compound,[Co（dien）2]（dienH3）（H3O）7[P2Mo5O23]2·14H2O, has been hydrothermallly synthesized by using Na2MoO4,CoCl2, H3PO4 and dien, and structurally characterized by elemental analysis, X-ray powder diffraction analysis, SEM, IR and TG analysis. The results show that the compound is composed of a polyanion [P2Mo5O23]2^12, complex [Co（dien）2]^2＋ cation, protonated [dienH3]^3＋ , and forteen crystallization water molecule.展开更多
Cobalt-doped ZnO powder samples were prepared by sol-gel and hydrothermal method combined.The prepared powder samples were characterized by X-ray diffraction（XRD）,scanning electron microscopy（SEM）,electron paramag...Cobalt-doped ZnO powder samples were prepared by sol-gel and hydrothermal method combined.The prepared powder samples were characterized by X-ray diffraction（XRD）,scanning electron microscopy（SEM）,electron paramagnetic resonance（EPR） and vibrating sample magnetometry（VSM）.XRD patterns show that all the samples have a single pure phase with wurtzite structure suggesting that Co2＋ occupied Zn2＋ sites in the ZnO crystal lattice.SEM images show that crystal grains of cobalt-doped ZnO are hexagonal cone or spheroidal.EPR pattern shows that all of the samples possess oxygen vacancy.Measurement of magnetism indicates that all the samples exhibit room temperature ferromagnetism（RTFM） embedded in a dominant diamagnetic or paramagnetic signal.The dominant signal turns from diamagnetic to paramagnetic with the increase of Co concentration.The magnetic behavior can attribute to defects and Co doping.展开更多
基金Project supported by the Fundamental Research Funds for the Central Universities,China(Grant No.2013XK07)
文摘TiO2 is a wide band gap semiconductor with important applications in photovoltaic cells. Vertically aligned Tit2 nanorod arrays （NRs） are grown on the fluorine-doped tin oxide （FTO） substrates by a multicycle hydrothermal synthesis process. The samples are characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, high-resolution transmission electron microscopy （HRTEM）, and selected-area electron diffraction （SAED）. It is found that dye-sensitized solar cells （DSSCs） assembled by the as-prepared Tit2 single-crystal NRs exhibit different trends under the condition of different nucleation and growth concentrations. Optimum cell performance is obtained with high nucleation concentration and low growth cycle concentration. The efficiency enhancement is mainly attributed to the improved specific surface area of the nanorod.
基金Funded by the Natural Science Foundation of Hubei Province (No. 2003ABA085) Key Laboratory for Silicate Materials Science and Engineering (Wuhan University of Technology), Ministry of Education (No.2003-SJSJJ-15)
文摘A new compound,[Co（dien）2]（dienH3）（H3O）7[P2Mo5O23]2·14H2O, has been hydrothermallly synthesized by using Na2MoO4,CoCl2, H3PO4 and dien, and structurally characterized by elemental analysis, X-ray powder diffraction analysis, SEM, IR and TG analysis. The results show that the compound is composed of a polyanion [P2Mo5O23]2^12, complex [Co（dien）2]^2＋ cation, protonated [dienH3]^3＋ , and forteen crystallization water molecule.
基金Project supported by the 46th Institute of China Electronics Technology Group Corporation(No.0231182346)
文摘Cobalt-doped ZnO powder samples were prepared by sol-gel and hydrothermal method combined.The prepared powder samples were characterized by X-ray diffraction（XRD）,scanning electron microscopy（SEM）,electron paramagnetic resonance（EPR） and vibrating sample magnetometry（VSM）.XRD patterns show that all the samples have a single pure phase with wurtzite structure suggesting that Co2＋ occupied Zn2＋ sites in the ZnO crystal lattice.SEM images show that crystal grains of cobalt-doped ZnO are hexagonal cone or spheroidal.EPR pattern shows that all of the samples possess oxygen vacancy.Measurement of magnetism indicates that all the samples exhibit room temperature ferromagnetism（RTFM） embedded in a dominant diamagnetic or paramagnetic signal.The dominant signal turns from diamagnetic to paramagnetic with the increase of Co concentration.The magnetic behavior can attribute to defects and Co doping.
