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Because of the high C–H bond energy as well as the non-polar feature of CH4 molecules, oxidation of methane under mild conditions remains a challenging task for both C1 utilization and atmospheric environmental cleansing. Here we report that by using a sol–gel method SrCO3 decorated SrTiO3 nanocatalysts (SrTiO3-S) with an average particle size of ∼25 nm can be readily prepared, which surprisingly show efficient performance for photocatalytic oxidation of methane with the activity close to fourfold of P25, a benchmark photocatalyst. Further investigation revealed a synergistic effect between SrCO3 and SrTiO3 when combined together into a composite material as both of which are totally inactive for methane oxidation if used alone. Gas adsorption characterization disclosed that the SrCO3 can adsorb methane and cannot adsorb carbon dioxide, whereas the SrTiO3 will preferentially adsorb CO2 instead of CH4. Photocurrent and photoluminescence measurements indicate that SrCO3 exhibits a negligible photocurrent response relative to the SrTiO3 semiconductor under simulated solar light illumination but the formation of the SrCO3/SrTiO3 junction structure (SrTiO3-S) helps reduce surface recombination of the photogenerated electrons and holes. All these results refer to the synergistic mechanism in which the SrCO3 acts as a trapping agent to adsorb methane and weaken its C–H bond while the SrTiO3 acts as a photocatalyst to activate and oxidize methane under light illumination. The underlying photooxidation mechanism is further investigated with the aid of in situ electron paramagnetic resonance and infrared spectroscopy. [ABSTRACT FROM AUTHOR]

Iron-nickel oxide porous nanosheets were synthesized via a controlled transformation from LDH precursors, which exhibit advanced OER performance with a low overpotential of 213 mV at 10 mA cm−2, small Tafel slope (32 mV dec−1) and long-term stability, due to their high specific surface area, abundant active sites, small charge transfer resistance, and suitable adsorption energy for intermediates. [ABSTRACT FROM AUTHOR]

Photocatalytic oxidation of ethylene continues to be a challenge at the frontier of chemistry. Previous investigations have shown that BiVO4 possesses strong photo-oxidative properties which can efficiently oxidize water and decompose organics in aqueous solutions; however, its conduction band minimum is too low to utilize the photo-generated electrons. Herein we report for the first time its effects on gaseous C2H4 photo-oxidation by fabricating YxBi1−xVO4 (x = 0.00–1.00) semiconductors with a polymeric method. Phase analysis identified that there are both a region of monoclinic and tetragonal phase coexistence (0.05 ≤x≤ 0.45) and a solid solution region (0.5 ≤x≤ 1.0). UV-visible diffusive reflectance spectra and Mott–Schottky analysis revealed that the incorporation of Y3+ widened the band gap by shifting upward the conduction band minimum as well as shifting downward the valance band maximum. Remarkable C2H4 photodegradation was obtained upon the Y0.85Bi0.15VO4 photocatalyst and its superior performance is ascribed to the synergistic effect of C2H4 adsorption, active oxygen species ṖO2− utilization, and relatively large surface area. The present study will be valuable for further investigation on both BiVO4 and hydrocarbons (HC) degradation. [ABSTRACT FROM AUTHOR]

A concise palladium-catalyzed method for oxidative C–H/C–H cross-coupling between benzothiazoles and thiophenes/thiazoles has been developed. This CDC reaction is insensitive to air and moisture with high functional group tolerance. [ABSTRACT FROM AUTHOR]

Because of the high C-H bond energy as well as the non-polar feature of CH 4 molecules, oxidation of methane under mild conditions remains a challenging task for both C1 utilization and atmospheric environmental cleansing. Here we report that by using a sol-gel method SrCO 3 decorated SrTiO 3 nanocatalysts (SrTiO 3 -S) with an average particle size of ∼25 nm can be readily prepared, which surprisingly show efficient performance for photocatalytic oxidation of methane with the activity close to fourfold of P25, a benchmark photocatalyst. Further investigation revealed a synergistic effect between SrCO 3 and SrTiO 3 when combined together into a composite material as both of which are totally inactive for methane oxidation if used alone. Gas adsorption characterization disclosed that the SrCO 3 can adsorb methane and cannot adsorb carbon dioxide, whereas the SrTiO 3 will preferentially adsorb CO 2 instead of CH 4 . Photocurrent and photoluminescence measurements indicate that SrCO 3 exhibits a negligible photocurrent response relative to the SrTiO 3 semiconductor under simulated solar light illumination but the formation of the SrCO 3 /SrTiO 3 junction structure (SrTiO 3 -S) helps reduce surface recombination of the photogenerated electrons and holes. All these results refer to the synergistic mechanism in which the SrCO 3 acts as a trapping agent to adsorb methane and weaken its C-H bond while the SrTiO 3 acts as a photocatalyst to activate and oxidize methane under light illumination. The underlying photooxidation mechanism is further investigated with the aid of in situ electron paramagnetic resonance and infrared spectroscopy.

Highly dispersed PtPd alloy nanocrystals (NCs) were firstly successfully encapsulated in microporous zeolitic imidazolate framework ZIF-8 (PtPd@ZIF-8) with tunable compositions by a "bottle around ship" approach. The PtPd@ZIF-8 catalyst showed excellent synergistic photocatalytic activity in the transformation of the adsorbed ethylene into CO2 and H2O at room temperature.

A one-pot two-step synthesis of versatile indenones has been developed. This palladium(II)-catalyzed transformation involves generation and condensation of ortho-functionalized 1,2-benzils from 2-(2-arylethynylphenyl)acetonitriles using Ph2SO as the oxidant. The resulting 3-cyanoindenones can be converted to various valuable molecules.

A base-promoted, microwave-assisted one-pot tandem reaction from simple 3-(1-alkynyl)chromones with 2-halobenzylic nitriles (esters or amides) for the synthesis of novel functional polycyclic chromenones has been developed. This tandem process involves multiple reactions, such as Michael addition and double cyclizations without a transition metal catalyst.