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The scaffold layer plays an important role in transporting electrons and preventing carrier recombination in mesoporous perovskite solar cells (PSCs), so the engineering of the interface between the scaffold layer and the light absorption layer has attracted widespread concern. In this work, vertically grown TiO2 nanorods (NRs) as scaffold layers are fabricated and further treated with TiCl4 aqueous solution. It can be found that a thin brookite TiO2 nanoparticle (NP) layer is formed by the chemical bath deposition (CBD) method on the surface of every rutile NR with a low annealing temperature (150 °C), which is beneficial for the infiltration and growth of perovskite. The PSC based on the TiO2 NR/brookite NP structure shows the best power conversion of 15.2%, which is 56.37% higher than that of the PSC based on bare NRs (9.72%). This complex structure presents an improved pore filling fraction and better carrier transport capability with less trap-assisted carrier recombination. In addition, low-annealing-temperature-formed brookite NPs possess a more suitable edge potential for electrons to transport from the perovskite layer to the electron collection layer when compared with high-annealing-temperature-formed anatase NPs. The brookite phase TiO2 fabricated at a low temperature presents great potential for flexible PSCs.

Nanomaterials play an important role in metal matrix composites (MMC). In this study, 3.0 wt.%, 6.0 wt.%, and 9.0 wt.% nano-AlN-particles-reinforced AA6061 (nano-AlN/AA6061) composites were successfully prepared by pressure infiltration technique and then hot extruded (HE) at 500 °C. The microstructural characterization of the composites after HE show that the grain structure of the Al matrix is significantly refined, varying from 2 to 20 μm down to 1 to 3 μm. Nano-AlN particles in the composites are agglomerated around the matrix, and the distribution of nano-AlN is improved after HE. The interface between AA6061 and nano-AlN is clean and smooth, without interface reaction products. The 3.0 wt.% nano-AlN/AA6061 composite shows an uppermost yield and supreme tensile strength of 333 MPa and 445 MPa, respectively. The results show that the deformation procedure of the composite is beneficial to the further dispersion of nano-AlN particles and improves the strength of nano-AlN/AA6061 composite. At the same time, the strengthening mechanism active in the composites was discussed.

In the present work, the properties of graphene-nanoplates/aluminum (GNPs/Al) composites with a heterogeneous matrix design were investigated. The advantage of the heterogeneous matrix was investigated by the finite element method. Then, 0.6 wt.% (GNPs/6061Al)/2024Al (heterogeneous matrix) and 0.6 wt.% GNPs/6061Al composites were prepared by ball milling, pressure infiltration technology, and hot extrusion. The aggregation of GNPs was eliminated and the interlayer slide of GNPs was observed. Mechanical property test results show that the mechanical properties of the heterogeneous matrix composite are better than that of a homogeneous matrix composite, including strength, elastic modulus, and plasticity. It is assumed that the heterogeneous matrix design enhances the non-uniform stress field during the deformation treatment. This improves the dispersion of GNPs, grain refinement, and produces the few-layer graphene (FLG), thus enhancing the strengthening effect of GNPs. Meanwhile, heterogeneous matrix design is thought to introduce more hardening mechanisms to increase the plasticity of materials and improve the intrinsic trade-off of strength and toughness.

Herein, a novel actinomorphic flower-like ZnO/Au/CdS nanorods ternary composite photocatalyst is prepared to extend the light-responsive range, reduce the photogenerated charge carriers recombination, and ultimately improve the water splitting performance. Flower-like ZnO nanorods are synthesized by a chemical bath method and the CdS nanoparticles are sensitized by successive ionic layer adsorption and reaction method. Then the Au nanoparticles as co-catalysts are introduced by the photodeposition method to modify the interface of ZnO/CdS for reducing the photogenerated electron recombination rate and further improving the performance of water splitting. Detailed characterizations and measurements are employed to analyse the crystallinity, morphology, composition, and optical properties of the flower-like ZnO/Au/CdS nanorods samples. As a result, the flower-like ZnO/Au/CdS nanorod samples present significantly enhanced water splitting performance with a high gas evolution rate of 502.2 μmol/g/h, which is about 22.5 and 1.5 times higher than that of the pure ZnO sample and ZnO/CdS sample. The results demonstrate that the flower-like ZnO/Au/CdS nanorods ternary composite materials have great application potential in photocatalytic water splitting for the hydrogen evolution field.

In a charge-coupled device (CCD)-based fast steering mirror (FSM) tracking control system, high control bandwidth is the most effective way to enhance the closed-loop performance. However, the control system usually suffers a great deal from mechanical resonances and time delays induced by the low sampling rate of CCDs. To meet the requirements of high precision and load restriction, fiber-optic gyroscopes (FOGs) are usually used in traditional FSM tracking control systems. In recent years, the MEMS accelerometer and gyroscope are becoming smaller and lighter and their performance have improved gradually, so that they can be used in a fast steering mirror (FSM) to realize the stabilization of the line-of-sight (LOS) of the control system. Therefore, a tentative approach to implement a CCD-based FSM tracking control system, which uses MEMS accelerometers and gyroscopes as feedback components and contains an acceleration loop, a velocity loop and a position loop, is proposed. The disturbance suppression of the proposed method is the product of the error attenuation of the acceleration loop, the velocity loop and the position loop. Extensive experimental results show that the MEMS accelerometers and gyroscopes can act the similar role as the FOG with lower cost for stabilizing the LOS of the FSM tracking control system.