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An in situ synthesized high volume fraction WC reinforced Ni-based composite coating was fabricated on a mild steel substrate by using a high power diode laser. Three kinds of single-layer coatings of different amounts of W+C powder and Ni60 powder and a five-layer coating with different amounts of W+C and Ni60 powders in each layer were prepared. This work showed that the multilayer coating possesses the highest hardness among all coatings, and the maximum hardness of the coatings was about 3.7 times more than that of the substrate. The gradient coating technology combined with the feature that WC particles were liable to sink in the bottom of coating were employed as a new idea for preparing the composite coating free of pores and cracks.

CH3NH3PbI3 thin films were prepared on glass substrates by pulsed laser deposition. The phase structural properties of the films deposited with different pulse repetition rates were analyzed carefully. The films deposited at 8 Hz and other rates show a single phase CH3NH3PbI3 and mixed CH3NH3PbI3-PbI2 phases, respectively. The prepared CH3NH3PbI3 film possesses absorption coefficients of 104 cm−1 in the visible region and the optical band gap of 1.66 eV. The CH3NH3PbI3/n-Si heterojunction device was fabricated. The I-V characteristics of the heterojunction in the dark and under illumination exhibit good rectifying behavior and fast photoresponse. The rise and fall time of the device were measured to be 58.8 μs and 1.9 μs.

The ZnO/g-C3N4 nanocomposites were synthesized by a single-step and scalable synthesis method through calcining the mixture of zinc acetate and urea. Two-dimensional shape, porous and carbon-doped microstructure were demonstrated by the SEM, TEM, N2 adsorption and XPS. ZnO/g-C3N4 nanocomposites were used as a photocatalyst for photodegradation of MB and MO under visible light irradiation. The photocatalytic performance of the porous sheet-like carbon-doped ZnO/g-C3N4 nanocomposites was higher than those of commercial P25, ZnO and g-C3N4.

The graphene supported SnO 2 nanoparticles (SnO 2 /graphene nanocomposites) were synthesized by a facile microwave-assisted polyol reduction method. The Na-storage performance of the as-prepared SnO 2 /graphene nanocomposites was evaluated as an anode material for sodium-ion batteries (SIBs), presenting a high initial reversible capacity of ~220 mA h g −1 at a current density of 0.1 A g −1 and an acceptable rate capability. This work provides an effective approach on synthesizing the SnO 2 /graphene nanocomposites and a potential anode material for SIBs.

Inverse opal cerium dioxide (CeO 2 ) is prepared with polystyrene (PS) microsphere opal template and sol–gel method, and characterized in detail. The opal template and inverse opal CeO 2 show different colors in the light of halogen tungsten lamp and have a long-range ordered three dimensional periodic structure. Comparing with the opal template, the size of the inverse opal CeO 2 shows shrinkage. The randomly selected positions of opal and inverse opal almost have the same peak position. The true filling factor of CeO 2 is different from the theoretical value and calculated by testing the reflecting peak. The inverse opal CeO 2 can modulate light by changing the diameter of air sphere and have directional stop band gap in the visible spectrum, which is expected to be some advanced and promising applications.

The TiO 2 /Eggshell, TiO 2 /Clamshell and TiO 2 /CaCO 3 loaded composites were prepared by sol–gel method and characterized by XRD and SEM. Their photocatalytic activities were measured through the degradation of Acid Red B under solar light irradiation. The influences of TiO 2 loaded content, heat-treated temperature and time on the photocatalytic activities were reviewed. The effects of irradiation time and dye initial concentration on the photocatalytic degradation were also investigated. The results showed that the photocatalytic activity can be greatly enhanced by appropriate TiO 2 loaded content.

In this study, we demonstrate the preparation of novel hierarchically porous β-Ni(OH) 2 microspheres constructed with nanoflakes through a simple solution-phase approach, using NiCl 2 ·6H 2 O and hexamethylenetetramine (HMTA) as the starting materials without adding any additives. NiO nanoparticles with the average diameter of 10 nm were obtained by calcining the as-prepared β-Ni(OH) 2 microspheres at 500 °C under ambient pressure. On the other hand, β-Ni(OH) 2 nanoplates were prepared by substituting HMTA with NaOH as the basic source, revealing the realization of shape-controlled synthesis of β-Ni(OH) 2 nanostructures. Optical property of the NiO nanoparticles was conducted by means of UV–vis spectrum, exhibiting small blue shift compared with the bulk counterpart. The possible mechanisms for selective formation of β-Ni(OH) 2 microspheres and nanoplates were in brief discussed.

Facile pyrolytic synthesis of copper zinc thin sulfide (Cu 2 ZnSnS 4 ) thin films are first introduced into quantum dot sensitized solar cells (QDSCs) for the counter electrode. The pore size of the pyrolytic synthesis Cu 2 ZnSnS 4 thin films is from 100 nm to 300 nm, and its charge transfer resistance is 37.10 Ω. The assembled QDSCs with the pyrolytic synthesis Cu 2 ZnSnS 4 thin films give short circuit photocurrent density ( J sc ) of 13.33 mA cm −2 , open circuit voltage ( V oc ) of 0.52 V, and fill factor (FF) of 0.45, corresponding to the photoelectric conversion efficiency ( η ) of 3.14%, while the QDSCs with platinized conducting glass give J sc of 13.38 mA cm −2 , V oc of 0.51 V, and FF of 0.34, corresponding to the η of 2.32%. Because the pyrolysis procedure is a facile, low cost and vacuum-free process, and has the advantage of obtaining various porous microstructure thin films and allowing deposition over large areas, the pyrolytic synthesis Cu 2 ZnSnS 4 thin films can be a promise alternative to the noble Pt counter electrode in QDSCs.

Cu 2 ZnSnS 4 (CZTS) thin films were successfully deposited using vacuum thermal evaporation from single quaternary CZTS semiconducting material powder source, followed by annealing at 300 °C for 40 min under high purity N 2 atmosphere. X-ray diffraction (XRD) patterns indicated that as-deposited CZTS thin films transformed from amorphous state into crystalline state with kesterite structure after annealing. Energy dispersive X-ray spectroscopy (EDS) determined the compositions of the CZTS thin films were Zn-poor, Sn-rich and S-rich. Scanning electron microscope (SEM) images, ultraviolet–visible–near infrared (UV–Vis–NIR) spectra and the Hall measurements showed the annealed CZTS thin film exhibited a smooth, densely packed and homogeneous surface, a direct band gap of 1.55 eV and a p-type conductivity. The fabricated photovoltaic device obtained a conversion efficiency of 0.36%, open-circuit voltage of 493 mV, short-circuit current density of 1.76 mA·cm − 2 , and fill factor of 0.42.