Search

Highlights: [•] Mesoporous TiO2 was prepared using an evaporation-induced self-assembly method. [•] The obtained TiO2 had hexagonal mesostructure with highly crystalline anatase phase. [•] Mesoporous TiO2 exhibited high sunlight-driven photocatalytic activity in dye degradation. [•] The charge-dependent photocatalytic behaviour of the mesoporous TiO2 was investigated. [Copyright &y& Elsevier]

Abstract: A pyrolysis synthesis method was developed to prepare ceramic nanoparticles for the fabrication of solid oxide fuel cells. Furfuryl alcohol was used as a polymerizable solvent to dissolve metal nitrates and then polymerized into poly(furfuryl alcohol) (PFA). During the pyrolysis at 600°C, a mixture of nitrates/PFA was converted into ceramic nanoparticles/carbon networks nanocomposite, and the carbon networks act as a barrier to prevent the aggregation of newly formed nanoparticles during particle crystallization. Dispersible nanoparticles with particle sizes ranging from 40nm to 200nm were obtained after burning off carbon networks in air. As an example, Ce0.8Sm0.2O1.9 nanoparticles were synthesized to prepare solid oxide fuel cells, and the fuel cells achieved maximum power densities of 444.5, 625.5 and 684mWcm−2 at 500°C, 550°C and 600°C, respectively. Our study shows that the pyrolysis synthesis method described here is promising for the effective synthesis of high quality ceramic nanoparticles. [Copyright &y& Elsevier]

Abstract: MnAPO-5 was prepared by a microwave-assisted vapor-phase transport method at 180°C in short times. The products were characterized by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectra, UV–vis spectroscopic measurement, NH3-temperature-programmed desorption and esterification reaction. It was found that dry gels prepared with aluminum isopropoxide, phosphoric acid and manganese acetate could be transferred to MnAPO-5 in the vapors of triethylamine and water by the microwave-assisted vapor-phase transport method at 180°C for less than 30min. The crystallization time was greatly reduced by the microwave heating compared with the conventional heating. The resulting MnAPO-5 exhibited much smaller particle sizes, higher surface areas and slightly higher catalytic activity in the esterification of acetic acid and butyl alcohol than those prepared by the conventional vapor-phase transport method and hydrothermal synthesis. [Copyright &y& Elsevier]

Graphical abstract Highlights • Ti-MOFs decorated by Pt or Au NPs with sizes of 3–9 nm have been synthesized. • Pt/MIL-125-NH 2 showed highest photocatalytic activity for alcohol oxidation. • M/MIL-125-NH 2 exhibited much better photocatalytic activity than that of M/MIL-125. Abstract Metal nanoparticles (NPs) decorated MOFs for photocatalysis has drawn enormous attention in the past decade. Here, a series of M/Ti-MOFs (M = Pt and Au, Ti-MOFs = MIL-125-NH 2 and MIL-125) has been synthesized through a facile post-synthetic method and the metal NPs highly dispersed on surface of MOFs with major sizes of 3–9 nm. Light absorption edges of scaffolds are crucial in the photocatalytic oxidation of benzyl alcohol over M/MIL-125-NH 2 and M/MIL-125. The conversion of benzyl alcohol over Pt/MIL-125-NH 2 is 2.4 times and 1.9 times higher than that of pristine MIL-125-NH 2 and Au/MIL-125-NH 2 , respectively. Besides, Pt/MIL-125-NH 2 photocatalyst also exhibited good activity for Cr(VI) reduction compared to that of MIL-125-NH 2. The enhanced photocatalytic activity of Pt/MIL-125-NH 2 is contributed to the rapid transfer of photo-induced electrons and decreased recombination of electron-hole pairs, which is verified by measurements of photocurrent and Electrochemical Impedance Spectroscopy. We hope that this study will provide worthy information for designing metal/MOFs or metal/MOFs-NH 2 photocatalysts. [ABSTRACT FROM AUTHOR]

Sodalite/NaTaO 3 composite was prepared by a one-pot hydrothermal synthesis method. Sodalite and NaTaO 3 grow interpenetrated, and the resulting composites have similar morphology as the pure sodalite. The sodalite/NaTaO 3 composite has a lower band gap of 3.35 eV due to the heterogeneous doping effect, and exhibits an enhanced photodegradation of methyl orange under UV irradiation as compared to the pure NaTaO 3 . A slight structure distortion is found for NaTaO 3 after removing sodalite by acid washing the sodalite/NaTaO 3 composite, and such result further confirms the co-growth of the two crystals. This one-pot hydrothermal method opens up new avenues for the preparation of photocatalytic composites. [ABSTRACT FROM AUTHOR]

• Cd x Zn 1-x S/ZnO nanocomposites were readily fabricated via a facile one-pot method. • The Cd/Zn molar ratios were tuned by altering the amounts of Na 2 S and Na 2 S 2 O 3. • Cd x Zn 1-x S/ZnO showed glorious performance on photocatalytic reduction of Cr(VI). • Cd 0.68 Zn 0.32 S/ZnO nanoparticles have tiny diameters of about 5−8 nm. Cd x Zn 1-x S/ZnO nanohybrids were fabricated by using mixed Na 2 S and Na 2 S 2 O 3 as the sulfur source via a facile one-pot synthesis. Cd x Zn 1-x S/ZnO with x = 0.54, 0.58, 0.62, 0.68 and 0.75 was successfully tuned by altering the molar ratio of Na 2 S and Na 2 S 2 O 3. Sole sulfur source Na 2 S or Na 2 S 2 O 3 could only generate Cd 0.5 Zn 0.5 S or CdS/ZnO, respectively. The in-situ co-growth of Cd x Zn 1-x S and ZnO makes them combine penetratingly in Cd x Zn 1-x S/ZnO nanohybrids, giving them a highly intimate contact. The natural matched band-edge positions and highly intimate contacts between Cd x Zn 1-x S and ZnO are conductive to charge separation and transfer. Benefiting from the structural and compositional merits, the optimized Cd x Zn 1-x S/ZnO nanohybrid with sizes of about 5−8 nm exhibited outstanding performance for Cr(VI) reduction under visible-light illumination. The newly designed one-pot synthetic strategy in this work may provide a brand-new pathway in developing high-efficiency multi-component photocatalysts for practical use. [ABSTRACT FROM AUTHOR]

• TiO 2 /ZnIn 2 S 4 nanocomposites were constructed by a facile one-pot synthesis. • The unique embedded structure of TiO 2 /ZnIn 2 S 4 was constructed. • TiO 2 /ZnIn 2 S 4 displays an excellent photocatalytic activity of Cr(VI) reduction. • The survival time and migration rate of photo-generated electrons were enhanced. Various TiO 2 /ZnIn 2 S 4 composites with an embedded structure have been developed by a facile one-pot synthesis. The activities of all samples were estimated by photocatalytic reduction of Cr(VI) under visible light (λ>420 nm). Results showed that the electrostatic interaction and self-assembly effect make TiO 2 nanoparticles inserting into ZnIn 2 S 4 nanosheets. The resulting TiO 2 /ZnIn 2 S 4 composites show much better photocatalytic performance for Cr(VI) reduction than that of pristine TiO 2 and ZnIn 2 S 4. Especially, the photocatalytic efficiency of T/ZIS-0.3 (TiO 2 loading of 30 wt%) is approximate 3 times as high as that of pristine ZnIn 2 S 4 (TiO 2 exhibited almost no activity). The embedded structure of TiO 2 /ZnIn 2 S 4 offers apparent increase of specific surface area, visible-light absorption and electrons transfer efficiency, which are responsible for the boosted photocatalytic activity. This work would inspire researchers to construct high-efficiency semiconductor composites for photocatalytic environmental governance. [ABSTRACT FROM AUTHOR]