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Composite photoelectrodes consisting of mesoporous TiO 2 and three-dimensional (3D) fluorine-doped tin oxide (FTO) conductive grid were fabricated. The nanostructures of prepared photoelectrodes were observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The power conversion performances of DSCs based on composite photoelectrodes were investigated by the current density–voltage ( J – V ) characteristics. Compared to TiO 2 based DSCs, DSCs based on FTO conductive grid exhibit higher short-circuit current density ( J sc ) and power conversion efficiency (PCE). The analysis on electrochemical impedance spectroscopy (EIS) reveals that the higher photoelectric conversion performance of DSCs with FTO conductive grid is attributed to more competitive electron collection than recombination.

为了降低第二代高温超导涂层导体的制备成本, 采用电化学法(ED), 在双轴织构的Ni-5at%W (Ni-5W)金属基带上分别成功制备出了具有较好c轴取向的La 2 Zr 2 O 7 (LZO)和Gd 2 Zr 2 O 7 (GZO)缓冲层. 通过与磁控溅射方法(MS)相结合, 制备出MS-CeO 2 /ED-RE 2 Zr 2 O 7 双层结构, 用以取代完全用磁控溅射方法(MS)制备的多层缓冲层结构. 电化学法得到的 60 nm LZO缓冲层的面内和面外织构半高宽分别为7.2°和6.8°, 同样厚度的GZO缓冲层的面内和面外半高宽分别为6.7°和5.8°. 之后用脉冲激光沉积(PLD)在ED-LZO/Ni-5W, ED-GZO/Ni-5W, MS-CeO 2 /ED-LZO/Ni-5W 三种结构的缓冲层上分别制备出具有超导性能的YBa 2 Cu 3 O 7- δ (YBCO)超导层.

Laser-induced periodic surface structures (LIPSS) were processed on the TiO2 bulk surface under the irradiation of 248 nm unpolarized KrF excimer laser pulses in air. Spatial LIPSS periods ranging from 2 to 3.5 μm are ascribed to the capillary wave. These microstructures were analyzed at different laser pulse numbers with the laser energy from 192 to 164 mJ. The scanning electron microscopy results indicated eventually stripes that have been disrupted as the increase in the laser pulse numbers, which is reasonably explained by the energy accumulating effect. In addition, investigations were concentrated on the surface modifications at pre-focal plane, focal plane and post-focal plane in the same defocusing amount. Compared with condition at pre-focal plane, in addition to the plasma produced at target, the air was also breakdown for the situation of post-focal plane. So it was reasonable that stripes appeared at pre-focal plane but not at post-focal plane.

Both TiO2 compact layer (d-TiO2) and Li-doped TiO2 compact layer (d-Li-TiO2) were deposited between nano-TiO2 and transparent conductive oxide (TCO) for dye sensitized solar cells (DSSC) by the technique of pulsed laser deposition (PLD). XRD pattern shows the compact layers are crystallized in anatase structure. Compared with FTO-based DSSC without compact layer, the open voltage decay measurement shows the novel structure can slow the decay of the open circuit voltage, indicating an effective suppression of back electrons transfer from TCO to the electrolyte by the dense buffer layers. In addition, the interface resistance between the nano-TiO2 and the TCO falls down due to the reduced energy band-gap of Li-doped TiO2, which makes it easier to transfer the generated elec- trons from conducting band of nano-TiO2 to TCO surface, leading an enlarged short current from 4.2 mA/cm 2 of FTO-based to 4.8 mA/cm 2 for that with d-TiO2 and 6.1 mA/cm 2 for d-Li-TiO2, respectively. Thus, the photo- voltaic energy conversion efficiency of DSSC based on the Li-doped TiO2 compact layer enhances as much as 42%

A newly structured tandem dye-sensitized solar cell (tandem DSC) based on stainless mesh was introduced, in which the electrode constituted a first TiO2 film on TCO and a second TiO2 film on stainless mesh. Negative inter- action between different dyes in this structure is less than that by normal method of cocktail-dyes dipping. The appli- cation of stainless mesh here reduces the loss of incident light, solves the problem of electronic connection between two different TiO2 films, as well as improves electron transport and collection. This tandem cell achieved a power conversion efficiency of 1.96% with short circuit current density of 8.4mA/cm 2 . Compared with normal mono-layer DSC with similar cell thickness, efficiency was improved about 62% by this tandem structure. Electrochemical im- pedance spectroscope (EIS) was used to analyze the electron transport in tandem DSC, and an equivalent circuit for tandem DSC was also proposed here. Meanwhile, the increased cell thickness and electron recombination on the sur- face of the stainless mesh have obvious influence on the photovoltaic performance.

将原料封装入真空石英管, 在873 K进行固相反应制备了Li掺杂的Cu 1- x Li x InSe 2 ( x = 0–0.4) 块体材料, 并对该材料的结构、电学和光学特性进行了系统性的研究。Li掺杂之后, 样品的晶体结构还保持黄铜矿结构, 并能得到更大的晶粒。而电阻率从1.98×102 Ω?cm增大到 2.73×108 Ω?cm。光学能隙也从0.90 eV 提高到1.33 eV, 增大了光伏开路电压。实验结果表明, Li掺杂的Cu 1- x Li x InSe 2 能有效提高光电材料的性能。

Explains the importance of the socialist market economy to the prosperity of China. Hand‐in‐glove with this important development is the role of internal audit in facilitating and sustaining the changes that are necessary. Audit has the dual function of serving the entity and the wider needs of the state. This involves a more sophisticated internal audit approach. Describes the more complex techniques utilized as a consequence.

YBaCuO (YBCO) bulk materials with large superconductive domains were fabricated using a small SmBa2Cu3Ox grain as the seed for growth. The capacities of strong flux pinning and well grain linking in the material have been shown in the investigations on magnetization loop and ac susceptibility. The strong flux pinning made it possible for the large YBCO bulk to capture a great deal of flux and keep the residual magnetism stable. The residual field intensity Hrem was shown to have a maximum of 0.125 T after the 0.5 T NdFeB magnetizing field was moved away. We did not find much decline of Hrem in a short time. The magnetized YBCO bulk produced repulsive force upon another YBCO bulk as the permanent magnet did. We measured and calculated the force between two YBCO bulks. The theoretical result was in agreement with the experimental one by and large.

A measurement method of constant-current-discharging voltage decay is established to characterize the band bending effect in the heterojunction of conducting glass/TiO2 for typical dye-sensitized solar cells. Furthermore, a dark-state electron transport regarding the TiO2 conduction band bending is proposed based upon the viewpoints of thermionic emission mechanism, which suggests an origin of the band bending effect in a theoretical model. This model quantitatively agrees well with our experimental results and indicates that both the Fermi level decay in TiO2 and the potential difference across the heterojunction will lead to the TiO2 conduction band bending downwards., Comment: 4 figures, 16 pages

A heterojunction-like device consisting of FTO/CeO2/electrolyte/FTO is established with distinct transport performance, where FTO denotes F-doped transparent conducting glass, and the electrolyte is LiI and I2 in acetonitrile. The resistive switching behavior is observed, being induced through applying sufficient negative pulse as well as light illumination. The endurance measurements confirm that the write/erase periodic operation is reproducible and stable in the present device. Furthermore, the retention measurements demonstrate that the information can be stored temporarily for about 100 seconds. A possible mechanism regarding the formation of diiodide radical is proposed to give a reasonable explanation for the observed switching behavior., Comment: 4 figures, 14 pages

The microstructure and defects in melt-textured growth (MTG) YBa2Cu3O7-x (YBCO) bulk material have been studied systematically using high-resolution transmission electron microscopy (HREM), and the relationship between the anisotropic critical current density Jc and the microstructure have been explored. The results indicate that the well-textured dense plate-shaped grains oriented parallel to the ab plane and the numerous intergrowth-type layered defects inside the plates are the two main structural characteristics in MTG YBCO. The former reduce weak links of grain boundaries, and the latter provide effective anisotropic pinning centres. The intergrowth-type layered defects parallel to the ab plane together with the well known (110) twin boundaries are responsible for the anisotropic behaviour of Jc, depending upon the orientation of the external magnetic field.

It is significant for low-cost preparation of YBa2Cu3O7−δ (YBCO) coated conductors to make clear the mechanism of orientation, copper segregation, and nucleation density in BaF2-derived YBCO crystallization. In the present work, a distinct nucleation mechanism was proposed based on a transient liquid phase induced by the size effect as well as near-equilibrium assumption. With this scheme the nucleation of YBCO prepared by metal–organic deposition (MOD) or the physical vapor deposition BaF2 process was semi-quantitatively analyzed, revealing that the direct driving force for nucleation is YBCO supersaturation in the liquid phase. The theoretical analysis on the nucleation orientation portion is evidenced by the experimental result.