MoS2/CNFs对电极膜厚对染料敏化太阳能电池性能影响

通过静电纺丝技术和水热法成功获得了碳纳米纤维负载二维层状硫化钼（MoS₂/CNFs）,将其作为对电极组装的染料敏化太阳能电池（DSSCs）表现出优异的电化学特性。在DSSCs制备过程中,对电极膜厚对电池性能有很大影响,所以本文重点探究了喷涂法制备的对电极膜厚对其组装的染料敏化电池光电性能影响,获得最佳对电极膜厚。实验结果表明当MoS₂/CNFs复合对电极材料膜厚为8 μm时,电池光电转换效率达到最大值7.78%。     

Ni3S4@C/CNFs对电极膜厚对染料敏化太阳能电池光伏性能的影响

采用静电纺丝技术和水热法合成了负载于碳纳米纤维表面的碳包覆Ni3S4纳米颗粒(Ni3S4@C/CNFs),利用喷涂法制备膜厚分别为2、4、6、7、8、9、10μm的Ni3S4@C/CNFs对电极。应用到染料敏化太阳能电池(DSSCs)中,探究Ni3S4@C/CNFs对电极的膜厚对于DSSCs光伏性能的影响。最终得出当Ni3S4@C/CNFs对电极膜厚为9μm时,DSSCs可以获得最高的光电转换效率(PCE)8.45%,也证明了对电极存在一个最佳膜厚,使DSSCs获得最优的光伏性能。     

ZnFe2O4/CNFs钛网基对电极膜厚对染料敏化太阳能电池性能的影响

通过静电纺丝和简单的一步水热法合成了碳纳米纤维（CNFs）负载的ZnFe₂O₄纳米颗粒（ZnFe₂O₄/CNFs）,并将其刮涂在钛网基底上作为染料敏化太阳能电池（DSSCs）的对电极进行组装测试,电池表现出优异的电化学性能。我们着重研究了不同膜厚对电极对DSSCs光电性能的影响。经过反复测试结果表明,当ZnFe₂O₄/CNFs复合电极材料膜厚为12 μm时存在最高的光电转换效率8.60%。     

氮掺杂多孔碳负载铁单原子对电极的膜厚对染料敏化太阳能电池性能的影响

利用分子笼封装前驱体而后热解的策略,制备了具有高催化活性的氮掺杂多孔碳(NPC)负载孤立的单个Fe原子(FeISAs/NPC)电催化剂,并作为对电极用于染料敏化太阳能电池(dye-sensitized solar cells,DSSCs)。通过电化学测试研究了FeISAs/NPC对电极的膜厚对DSSCs光电性能的影响。测试结果表明,Fe-ISAs/NPC对电极的膜厚为16μm时,DSSCs的光电转换效率最高(8.03%)。     

聚合物/TiO2杂化纳米纤维微孔膜的制备及其在染料敏化太阳能电池中的应用

利用静电纺丝技术,制备了不同的聚合物/TiO2杂化纳米纤维微孔膜,吸附液体电解质后形成聚合物/TiO2杂化纳米纤维微孔膜准固态电解质,应用于制备准固态染料敏化太阳能电池(DSSCs).测试了电纺聚合物纳米纤维微孔膜电解质的吸液率、孔隙率、离子电导率等参数,研究了纳米纤维微孔膜准固态电解质DSSCs的光伏性能.结果显示,TiO2的掺入可提高聚合物/TiO2杂化纳米纤维微孔膜对液态电解质的浸润扩散性能,从而提高纳米纤维微孔膜对液态电解质的吸附能力.组装的DSSCs的光电转换效率可达液态电解质的90%以上,并具有较好的长期工作稳定性.     

聚吡咯/石墨复合对电极在染料敏化太阳能电池中的应用研究

通过化学氧化法制备了聚吡咯纳米粒子, 并将其与石墨共混旋涂于ITO导电玻璃上, 作为染料敏化太阳能电池的对电极. 通过SEM观察到聚吡咯纳米粒子粒径在80～100 nm之间, 循环伏安测试表明聚吡咯电极对I₂/I^－电解质氧化还原体系具有较好的催化能力. 光伏电池的电化学交流阻抗测试结果说明掺入石墨后可有效降低聚吡咯对电极的电荷转移阻抗. 以钌染料N719为光敏剂, 聚吡咯/石墨复合电极为对电极组装成的染料敏化太阳能电池, 在AM 1.5 (100 mW•cm^－2) 的模拟太阳光照射下, 得到6.01%的光电转换效率, 达到相同条件下铂对电极性能的92%.     

掺P25水热法制备纳晶多孔TiO2薄膜电极

以水热法为基础,向其溶胶中掺入适量的P25(二氧化钛粉体),来制备纳晶TiO₂胶体,以纳晶TiO₂为电子传输体组装染料敏化太阳能电池.通过XRD、SEM、UV-vis和电池的光电性能测试,来分析掺入P25对染料敏化太阳能电池性能的影响.结果表明,加入适量P25([P25]/[Ti]=0.2)后,染料敏化太阳能电池性能达到最佳值,在100 mW/cm²光照条件下,光电转换效率达到5.4%.     

浆料的制备方法对染料敏化太阳能电池性能优化影响

在TiO_2粉末中加入乙基纤维素松油醇溶液混合均匀,经研磨得到适合丝网印刷制备薄膜的TiO_2浆料,制备出TiO_2光阳极薄膜并组装成染料敏化太阳能电池(DSSCs)。采用XRD、SEM对样品形貌表征,并利用光电流密度-电压(I-V)曲线测试DSSCs的光电性能,讨论了浆料原料的配比方法、涂覆层数以及烧结方式对电池的性能影响。研究表明,由0.5 g TiO_2粉末、5%乙基纤维素松油醇溶液制备的浆料,用丝网印刷涂覆8层,通过煅烧—管式炉降至室温—煅烧的方法可制得最优质的DSSCs光阳极薄膜。     

低成本WS_2染料敏化电池对电极的低温制备

采用简单的方法,在低温条件下制作了高效的WS2对电极,并用X射线衍射仪(XRD)、显微共焦拉曼光谱仪(Raman)和扫描电子显微镜(SEM)对材料的物理特性进行了表征.WS_2对电极的电化学催化活性用循环伏安(CV)和光电流密度-电压特性(I-V)来评价.利用所制备WS_2对电极组装的染料敏化太阳能电池的光电转换效率为5.48%略低于Pt对电极(6.6%).研究表明WS_2是一种很有前景的染料敏化太阳能电池Pt对电极替代材料.     

纳米二氧化钛的水热法制备及在染料敏化太阳能电池中的应用

分别在盐酸和冰醋酸溶液中水解钛酸四正丁酯,得到前驱体,通过水热法制备锐钛矿型二氧化钛纳米晶体.以纳米二氧化钛为电子传输体组装染料敏化电池,通过XRDI、CP、DRS、TEM、SEM和电池的光电性能测试,研究制备的二氧化钛对电池光电性能的影响.结果表明,水热反应温度对染料敏化太阳能电池光电性能有较大影响,在有机酸介质中制备的二氧化钛具有较高的光电转换效率.     

Sol-gel synthesis of K3InF6 and structural characterization of K2InC10O10H6F9, K3InC12O14H4F18 and K3InC12O12F18

K₃InF₆ is synthesized by a sol-gel route starting from indium and potassium acetates dissolved in isopropanol in the stoichiometry 1:3, with trifluoroacetic acid as fluorinating agent. The crystal structures of the organic precursors were solved by X-ray diffraction methods on single crystals. Three organic compounds were isolated and identified: K₂InC₁₀O₁₀H₆F₉, K₃InC₁₂O₁₄H₄F₁₈ and K₃InC₁₂O₁₂F₁₈. The first one, deficient in potassium in comparison with the initial stoichiometry, is unstable. In its crystal structure, acetate as well as trifluoroacetate anions are coordinated to the indium atom. The two other precursors are obtained, respectively, by quick and slow evaporation of the solution. They correspond to the final organic compounds, which give K₃InF₆ by decomposition at high temperature. The crystal structure of K₃InC₁₂O₁₄H₄F₁₈ is characterized by complex anions [In(CF₃COO)₄(OH_x)₂]^(5−2x)− and isolated [CF₃COOH_2−x]^(x−1)− molecules with x=2 or 1, surrounded by K⁺ cations. The crystal structure of K₃InC₁₂O₁₂F₁₈ is only constituted by complex anions [In(CF₃COO)₆]³⁻ and K⁺ cations. For all these compounds, potassium cations ensure only the electroneutrality of the structure. IR spectra of K₂InC₁₀O₁₀H₆F₉ and K₃InC₁₂O₁₂F₁₈ were also performed at room temperature on pulverized crystals.     

Structure Study of Bi2.5Na0.5Ta2O9 and Bi2.5Nam−1.5NbmO3m+3 (m=2-4) by Neutron Powder Diffraction and Electron Microscopy

The crystal structures of Bi_2.5Na_0.5Ta₂O₉ and Bi_2.5Na_m-1.5Nb_mO_3m+3 (m=3,4) have been investigated by the Rietveld analysis of their neutron powder diffraction patterns (λ=1.470 Å). These compounds belong to the Aurivillius phase family and are built up by (Bi₂O₂)²⁺ fluorite layers and (A_m-1B_mO_3m+1)^2- (m=2-4) pseudo-perovskite slabs. Bi_2.5Na_0.5Ta₂O₉ (m=2) and Bi_2.5Na_2.5Nb₄O₁₅ (m=4) crystallize in the orthorhombic space group A2₁am, Z=4, with lattice constants of a=5.4763(4), b=5.4478(4), c=24.9710 (15) and a=5.5095(5), b=5.4783(5), c=40.553(3) Å, respectively. Bi_2.5Na_1.5Nb₃O₁₂ (m=3) has been refined in the orthorhombic space group B2cb, Z=4, with the unit-cell parameters a=5.5024(7), b=5.4622(7), and c=32.735(4) Å. In comparison with its isostructural Nb analogue, the structure of Bi_2.5Na_0.5Ta₂O₉ is less distorted and bond valence sum calculations indicate that the Ta-O bonds are somewhat stronger than the Nb-O bonds. The cell parameters a and b increase with increasing m for the compounds Bi_2.5Na_m-1.5Nb_mO_3m+3 (m=2-4), causing a greater strain in the structure. Electron microscopy studies verify that the intergrowth of mixed perovskite layers, caused by stacking faults, also increases with increasing m.     

La3Ru8B6 and Y3Os8B6, new members of a homologous series R(A)nM3n−1B2n

Two new compounds, La₃Ru₈B₆ and Y₃Os₈B₆, were synthesized by arc melting the elements. Their structural characterization was carried out at room temperature on as-cast samples by using X-ray diffractometry. According to X-ray single-crystal diffraction results these borides crystallize in Fmmm space group (no. 69), Z=4, a=5.5607(1) Å, b=9.8035(3) Å, c=17.5524(4) Å, ρ=8.956 Mg/m³, μ=25.23 mm⁻¹ for La₃Ru₈B₆ and a=5.4792(2) Å, b=9.5139(4) Å, c=17.6972(8) Å, ρ=13.343 Mg/m³, μ=128.23 mm⁻¹ for Y₃Os₈B₆. The crystal structure of La₃Ru₈B₆ was confirmed from Rietveld refinement of X-ray powder diffraction data. Both La₃Ru₈B₆ and Y₃Os₈B₆ compounds are isotypic with the Ca₃Rh₈B₆ compound and their structures are built up from CeCo₃B₂-type and CeAl₂Ga₂-type structural fragments taken in ratio 2:1. They are the members of structural series R(A)_nM_3n−1B_2n with n=3 (R is the rare earth metal, A the alkaline earth metal, and M the transition metal). Structural and atomic parameters were also obtained for La_0.94Ru₃B₂ compound from Rietveld refinement (CeCo₃B₂-type structure, P6/mmm space group (no. 191), a=5.5835(9) Å, c=3.0278(6) Å).     

Composition-induced phase transition in Ca14Zn6−xGa10+xO35+x/2 (x=0.0 and 0.5)

Novel complex oxides Ca₁₄Zn₆Ga₁₀O₃₅ and Ca₁₄Zn_5.5Ga_10.5O_35.25 were prepared in air at 1200 °C, 72 h. Refinements of their crystal structures using X-ray powder diffraction data showed that Ca₁₄Zn₆Ga₁₀O₃₅ is ordered (S.G. F23, =0.0458, R_p=0.0485, R_wp=0.0659, χ²=1.88) and Ca₁₄Zn_5.5Ga_10.5O_35.25 disordered (S.G. F432, =0.0346, R_p=0.0601, R_wp=0.0794, χ²=2.82) variants of the crystal structure of Ca₁₄Zn₆Al₁₀O₃₅. In the crystal structure of Ca₁₄Zn₆Ga₁₀O₃₅, there are large empty voids, which could be partially occupied by additional oxygen atoms upon substitution of Zn²⁺ by Ga³⁺ as in Ca₁₄Zn_5.5Ga_10.5O_35.25. These oxygen atoms are introduced into the crystal structure of Ca₁₄Zn_5.5Ga_10.5O_35.25 only as a part of four tetrahedra (Zn, Ga)O₄ groups sharing common vertex. This creates a situation where even a minor change in the chemical composition leads to considerable anion and cation disordering resulting in a change of space group from F23 (no. 196) to F432 (no. 209).     

Li2O-TiO2-SiO2-P2O5和Li2O-TiO2-Al2O3-P2O5体系锂离子固体电解质的制备及性能研究

一些具有NASICON型网格结构的固体电解质具有高的电导率和好的稳定性,NASICON的意思是Na Super Ionic Conductor[1]。当NaZr2(PO4)3中P5 被Si4 部分取代时便可以得到具有NASICON结构的Na1 xZr2SixP3-xO12体系,其具有高的钠离子电导率。然而有相同结构的Li1 xZr2SixP3-xO12体系的离子电导率却很低,这是因为Li 半径太小,而NASICON三维网格结构的离子通道太大,两者不匹配而使电导率下降[2]。但当LiZr2(PO4)3中Zr4 被离子半径小些的Ti4 取代,所得LiTi2(PO4)3的通道就与Li 半径相匹配,适合于锂离子的迁移,从而使其电导率…     

The crystal chemistry of Bi6TP2O15+x, T=Fe, Ni, Zn: Isomorphism and polymorphism, structural relationship to Bi6TiP2O16

The crystal structures of compounds with nominal compositions Bi₆FeP₂O_15+x (I), Bi₆NiP₂O_15+x (II) and Bi₆ZnP₂O_15+x (III) were determined from single-crystal X-ray diffraction data. They are monoclinic, space group I2, Z=2. The lattice parameters for (I) are a=11.2644(7), b=5.4380(3), c=11.1440(5) Å, β=96.154(4)°; for (II) a=11.259(7), b=5.461(4), c=11.109(7) Å, β=96.65(1)°; for (III) a=19.7271(5), b=5.4376(2), c=16.9730(6) Å, β=131.932(1)°. Least squares refinements on F² converged for (I) to R1=0.0554, wR₂=0.1408; for (II) R₁=0.0647, wR₂=0.1697; for (III) R₁=0.0385, wR₂=0.1023. The crystals are complexly twinned by 2-fold rotation about , by inversion and by mirror reflection. The structures consist of edge-sharing articulations of OBi₄ tetrahedra forming layers in the a-c plane that then continue by edge-sharing parallel to the b-axis. The three-dimensional networks are bridged by Fe and Ni octahedra in (I) and (II) and by Zn trigonal bipyramids in (III) as well as by oxygen atoms of the PO₄ moieties. Bi also randomly occupies the octahedral sites. Oxygen vacancies exist in the structures of the three compounds due to required charge balances and they occur in the octahedral coordination polyhedron of the transition metal. In compound (III), no positional disorder in atomic sites is present. The Bi-O coordination polyhedra are trigonal prisms with one, two or three faces capped. Magnetic susceptibility data for compound (I) were obtained between 4.2 and 350 K. Between 4.2 and 250 K it is paramagnetic, μ_eff=6.1 μ_B; a magnetic transition occurs above 250 K.     

Synthesis and structural characterization of Al7C3N3-homeotypic aluminum silicon oxycarbonitride, (Al7−xSix)(OyCzN6−y−z) (x∼1.2, y∼1.0 and z∼3.5)

A new aluminum silicon oxycarbonitride, (Al_5.8Si_1.2)(O_1.0C_3.5N_1.5), has been synthesized and characterized by X-ray powder diffraction (XRPD), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX) and electron energy loss spectroscopy (EELS). The title compound is hexagonal with space group P6₃/mmc and unit-cell dimensions a=0.322508(4) nm, c=3.17193(4) nm and V=0.285717(6) nm³. The atom ratios of Al:Si and those of O:C:N were, respectively, determined by EDX and EELS. The initial structural model was successfully derived from the XRPD data by the direct methods and further refined by the Rietveld method. The crystal is most probably composed of four types of domains with nearly the same fraction, each of which is isotypic to Al₇C₃N₃ with space group P6₃mc. The existence of another new oxycarbonitride (Al_6.6Si_1.4)(O_0.7C_4.3N_2.0), which must be homeotypic to Al₈C₃N₄, has been also demonstrated by XRPD and TEM.     

A new 2212-type stair like structure: Bi14Sr21Fe12O61, m=5 member of the generic [Bi2Sr3Fe2O9]m[Bi4Sr6Fe2O16] family

A new oxide, Bi₁₄Sr₂₁Fe₁₂O_61, with a layered structure derived from the 2212 modulated type structure Bi₂Sr₃Fe₂O₉, was isolated. It crystallizes in the I2 space group, with the following parameters: a=16.58(3) Å, b=5.496(1) Å, c=35.27(2) Å and β=90.62°. The single crystal X-ray structure determination, coupled with electron microscopy, shows that this ferrite is the m=5 member of the [Bi₂Sr₃Fe₂O₉]_m[Bi₄Sr₆Fe₂O₁₆] collapsed family. This new collapsed structure can be described as slices of 2212 structure of five bismuth polyhedra thick along , shifted with respect to each other and interconnected by means of [Bi₄Sr₆Fe₂O₁₆] slices. The latter are the place of numerous defects like iron or strontium for bismuth substitution; they can be correlated to intergrowth defects with other members of the family.     

Non-centrosymmetric Ba3Ti3O6(BO3)2

The compound previously reported as Ba₂Ti₂B₂O₉ has been reformulated as Ba₃Ti₃B₂O₁₂, or Ba₃Ti₃O₆(BO₃)₂, a new barium titanium oxoborate. Small single crystals have been recovered from a melt with a composition of BaTiO₃:BaTiB₂O₆ (molar ratio) cooled between 1100°C and 850°C. The crystal structure has been determined by X-ray diffraction: hexagonal system, non-centrosymmetric space group, a=8.7377(11) Å, c=3.9147(8) Å, Z=1, wR(F²)=0.039 for 504 unique reflections. Ba₃Ti₃O₆(BO₃)₂ is isostructural with K₃Ta₃O₆(BO₃)₂. Preliminary measurements of nonlinear optical properties on microcrystalline samples show that the second harmonic generation efficiency of Ba₃Ti₃O₆(BO₃)₂ is equal to 95% of that of LiNbO₃.     

一维纳米Co_3O_4,Ag/Co_3O_4及CuO/Co_3O_4的合成与电催化性能(英文)

采用水热合成法制备了Co3O4及复合Ag/Co3O4、CuO/Co3O4一维纳米产品。用XRD,FE-SEM和TEM手段对产品进行了表征。采用循环伏安法研究了合成产品修饰的玻碳电极在碱性溶液中对对硝基苯酚的电催化还原性能。与裸玻碳电极相比,1mmol·L-1的对硝基苯酚在用Co3O4、特别是CuO/Co3O4修饰的玻碳电极上还原的峰电流明显增大,用Ag/Co3O4(Ag/Co原子比分别为1∶5和2∶5)修饰的玻碳电极催化还原对硝基苯酚时,尽管还原峰电流增大不是太大,但其峰电位明显降低(分别降低0.265和0.371V)。