Hydrothermal synthesis of In2O3 nanoparticles hybrid twins hexagonal disk ZnO heterostructures for enhanced photocatalytic activities and stability

Abstract In2O3 nanoparticles hybrid twins hexagonal disk (THD) ZnO with different ratios were fabricated by a hydrothermal method. The as-obtained ZnO/In2O3 composites are constituted by hexagonal disks ZnO with diameters of about 1 μm and In2O3 nanoparticles with sizes of about 20–50 nm. With the increase of In2O3 content in ZnO/In2O3 composites, the absorption band edges of samples shifted from UV to visible light region. Compared with pure ZnO, the ZnO/In2O3 composites show enhanced photocatalytic activities for degradation of methyl orange (MO) and 4-nitrophenol (4-NP) under solar light irradiation. Due to suitable alignment of their energy band-gap structure of the In2O3 and ZnO, the formation of type п heterostructure can enhance efficient separation of photo-generate electro-hole pairs and provides convenient carrier transfer paths

Facile synthesis of novel CoWO₄/FeWO₄ hetrocomposite with efficient visible light photocatalytic degradation and hydrogen evolution aspects

Tungstate-based nanomaterials exhibit efficient photocatalytic performance and offer several advantages owing to their electrical and superior optical features, charge transport potentials, and superb corrosion resistance. The objective of the present study is to fabricate cobalt tungstate (CoWO4), Ferric tungstate (FeWO4) and CoWO4/FeWO4 heterojunction composite photocatalysts using a hydrothermal route with various molar concentrations (2:1, 1:1, 1:2, 1:5). The model pollutant Methyl Orange (MO) and Congo Red (CR) azo dyes were degraded 98.26% and 99.61% in 150 min by the as-synthesized CoWO4/FeWO4 at a molar concentration ratio of 1:2. A feasible photodegradation mechanism is purposed and the optimum values for different parameters are also evaluated by considering two different dyes as model organic pollutants. Hydrogen production efficiency reaches up to 36 μmolg−1 h−1 under visible light over 1:2 CoWO4/FeWO4. This work may open new possibilities for the use of CoWO4/FeWO4 composite for potential applications such as the hydrothermal synthesis of composites and their photocatalytic wastewater remedy and as hydrogen evolution applications.</p

In situ polarization and dielectric property measurements of Pb(Zr0.52Ti0.48)O3 ferroelectric nanocrystals

Pb(Zr0.52Ti0.48)O3/polycarbonate (PZT/PC) composite films with different concentration of PZT ferroelectric nanocrystals are prepared. The polarization and dielectric relaxation behavior of PZT ferroelectric nanocrystals are characterized using in situ transmittance and X-ray diffraction (XRD) measurements for the first time. It’s found that 10% PZT/PC composite film has the largest orientation change and negligible dielectric relaxation after poling (the φ value of 13.8% is almost constant with time even for 168 h). Based on the XRD results, we consider that the preferential orientation of PZT nanocrystals to align in PC matrix after poling is [001] direction

Preparation and Photocatalytic Performance of Hollow Structure LiNb3O8 Photocatalysts

Abstract Hollow structure LiNb3O8 photocatalysts were prepared by a hydrothermal method assisting sintering process. The particles’ aggregation to form hollow structures with obvious cavities can be attributed to the Li element volatilization during calcination process. All the LiNb3O8 powders show high photocatalytic efficiency of degradation of methylene blue (MB), especially for the sample calcined at 700 °C (LNO700), with only 3 h to completely decompose MB. The photo-degradation of MB follows the pseudo-first-order kinetics, and the obtained first-order rate is 0.97/h. The larger degradation rate of LNO700 can be attributed to its hollow structure which provides a larger specific surface area and more active sites to degrade the MB molecules. The cycling test of photo-degradation and adsorption of MB over LNO700 powder indicates that the hollow structure of the LiNb3O8 photocatalyst is stable and the LiNb3O8 photocatalyst is an efficient photocatalyst with good reusability, confirmed by the XRD and X-ray photoelectron spectroscopy tests before and after photo-degradation of MB

Hydrothermal-Assisted Sintering Strategy Towards Porous- and Hollow-Structured LiNb3O8 Anode Material

Abstract Porous- and hollow-structured LiNb3O8 anode material was prepared by a hydrothermal-assisted sintering strategy for the first time. The phase evolution was studied, and the formation mechanism of the porous and hollow structure was proposed. The formation of the unique structure can be attributed to the local existence of liquid phase because of the volatilization of Li element. As the anode material, the initial discharge capacity is 285.1 mAhg−1 at 0.1 C, the largest discharge capacity reported so far for LiNb3O8. Even after 50 cycles, the reversible capacity can still maintain 77.6 mAhg−1 at 0.1 C, about 2.5 times of that of LiNb3O8 samples prepared by traditional solid-state methods. The significant improvement of Li storage capacity can be attributed to the special porous and hollow structure, which provides a high density of active sites and short parallel channels for fast intercalation of Li+ ions through the surface

Additional file 1: of Hydrothermal synthesis of In2O3 nanoparticles hybrid twins hexagonal disk ZnO heterostructures for enhanced photocatalytic activities and stability

Figure S1 The temporal evolution of spectral of MO photodecomposition by Zn-In-4. (DOC 571 kb