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Abstract: Bismuth titanates (BTs) can be fabricated by electrospinning combined with calcination at different temperatures. BiOCl/Bi2Ti2O7 nanorod heterostructures were obtained at 500 °C. They possess excellent photocatalytic efficiency and stability for tetracycline hydrochloride (TC‐HCl) degradation under simulated solar light. The excellent catalytic activity is predominantly attributed to the heterostructure between BiOCl and Bi2Ti2O7, which accelerates the separation of photogenerated carriers while the narrow band gap of Bi2Ti2O7 enhances solar energy utilization. On the basis of energy band engineering, scavenger tests, and LC‐HRMS analysis, a possible degradation pathway of TC‐HCl and photocatalytic mechanism were proposed. Our work can predict a facile route for achieving high photocatalytic performance of Bi2Ti2O7‐based materials in the application of TC‐HCl degradation. [ABSTRACT FROM AUTHOR]

Ag/AgCl composite as an alternative visible-light photocatalyst has attracted extensive interests; however, the high charge carrier recombination rate and short-term photocatalytic durability limit their practical application. In the present work, TiO 2 hollow nanofibers (ELTiO 2 ) grafted Ag/AgCl is fabricated via electrospinning-precipitation method. Compared with Ag/AgCl and Ag/AgCl-SGTiO 2 (sol-gel synthetized TiO 2 ), 2.89 and 1.59-fold enhancement in the photodegradation rate toward MO is observed over Ag/AgCl-ELTiO 2 under visible light irradiation. The enhancement of photocatalytic activity is mainly attributed to the higher content of the exposed AgCl {1 1 1} facet, which is beneficial for the separation of photogenerated carriers and accounts for more active sites. Moreover, Ag/AgCl-ELTiO 2 shows better photostability than bare Ag/AgCl. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: A series of electrospun LaCoO3 perovskites derived from CoX2 (X = CH3COO–, NO3–) were prepared and investigated for total propane oxidation. It is shown that pure rhombohedral perovskite LaCoO3 from Co(CH3COO)2 can be obtained at a relatively low temperature, 400 °C, benefitting from the complexation effect of CH3COO–. On the other hand, CH3COO– can accelerate the complete decomposition of polymer. The low‐temperature process can protect LaCoO3 nanoparticles from growing up. As a result, Co(CH3COO)2‐derived catalysts exhibit better propane oxidation activity than the ones suffered the same thermal treatment by using Co(NO3)2. XPS and H2‐TPR analysis provide that there is subtle change in Co3+/Co2+ on bulk/surface of Co(CH3COO)2‐derived catalysts prepared at different temperatures, giving rise to similar propane oxidation activities. Moreover, the result of cyclic stability test over 400 °C obtained catalyst shows little deactivation, demonstrating a good thermal stability. Our study can provide a feasible route for energy‐saving synthesis of LaCoO3 catalyst applied in the catalytic oxidation of volatile organic compounds (VOCs). [ABSTRACT FROM AUTHOR]

[Display omitted] • Co species are active sites for C 3 H 8 oxidation despite Pt loading. • Coaxial electrospinning anchors Pt on both surface and bulk phase. • Coaxial electrospun Pt/LaCoO 3 gives the best C 3 H 8 oxidation activity. • Surface Pt favors Co3+ → Co2+ while bulk Pt accelerates Co2+ → Co0+. • Redox property and lattice oxygen mobility are crucial. The effect of location sites of platinum (Pt) nanoparticles on LaCoO 3 support for complete catalytic oxidation of propane (C 3 H 8) was investigated. Pt nanoparticles were anchored on the surface, bulk and surface/bulk of LaCoO 3 by using three different loading methods: incipient-wetness impregnation, single-needle electrospinning and coaxial electrospinning, respectively, followed by a simple 300 °C H 2 reduction process. The obtained catalysts were systematically characterized. It turns out that one step synthesis of coaxial electrospun Pt/LaCoO 3 nanotubes with both surface and bulk Pt species exhibits a relatively more efficient catalytic activity, where surface Pt favors the reduction of Co3+ to Co2+ and bulk Pt accelerates that of Co2+ to Co0. Meanwhile, Co species are active sites for C 3 H 8 oxidation despite Pt loading, but the enhanced redox property and oxygen mobility upon Pt loading are crucial for the Mars-van Krevelen mechanism obeyed total C 3 H 8 oxidation. Additionally, good thermal stability is found over coaxial electrospun Pt/LaCoO 3 , removing propane at a temperature of 450 °C over 48 h without a significant decrease in propane conversion. The addition of water vapor has a little inhibition effect on the catalytic activity under the reaction condition. Such route of Pt anchoring will provide an effective means for designing highly efficient perovskite based catalysts with low precious loadings for total oxidation reaction. [ABSTRACT FROM AUTHOR]

A one-dimensional (1D) core-shell of Co-Ce oxide has been prepared by multifluidic coaxial electrospinning method and evaluated for the total oxidation of propane (C 3 H 8). Activity and morphological characterizations show that the CeO 2 @Co 3 O 4 nanofiber catalyst, of which the core is CeO 2 and the shell is Co 3 O 4 , exhibits excellent oxidation activity. The exposed Co 3 O 4 grown on the outside of the fibers can rapidly react with C 3 H 8 while CeO 2 with high oxygen storage capacity in the inside is conductive to the enhanced oxidation rate. Besides, the continuous grain boundary provides a fast mass transfer channel for lattice oxygen, and rich oxygen vacancies favor the mobility of active oxygen species. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTs) confirms that the CeO 2 @Co 3 O 4 catalyst have a faster rate of C 3 H 8 adsorption and better oxidation activity with respect to the counterpart using a single-needle electrospinning method. Moreover, the CeO 2 @Co 3 O 4 catalyst displays excellent thermal stability, and strong resistance against 5 vol% H 2 O and 5 vol% CO 2 at both 300 and 400 °C. Our strategy can give some new insights into morphological engineering to promote active oxygen mobility via the construction of one-dimensional core-shell of metal oxides for catalytic oxidation of VOCs. ga1 • CeO 2 @Co 3 O 4 nanofibers were prepared by multifluidic coaxial electrospinning. • Co 3 O 4 shell rapidly reacts with C 3 H 8 while CeO 2 core enhances oxygen migration. • Continuous grain boundary provides a fast mass transfer channel for lattice oxygen. • Abundant oxygen vacancies favor the mobility of active lattice oxygen. • Superior oxidation activity, thermal stability and H 2 O/CO 2 resistance were obtained. [ABSTRACT FROM AUTHOR]