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A significant role of MOFs as heterogeneous photocatalysts in enabling organic transformations. • Light harvesting Ru-polypyridyl complexes were incorporated into a semiconductor-like metal-organic framework (MIL-125). • Disclosing photoinduced electron transfer among photocatalysis. • The prepared Ru(bpy) 3 @MIL-125 exhibited good recyclability during reaction. Visible-light-driven selective photocatalytic organic synthesis has recently become a topic of great interest due to its environmental friendliness and sustainability. It is demanding for photocatalysis to utilize the wider range of light, such as visible light, and its performance is often plagued by the sluggish separation of photogenerated charge carriers. An approach is now reported to address these issues by incorporating light harvesting RuII-polypyridyl complexes into a semiconductor-type metal-organic framework (MIL-125). Delightedly, the obtained Ru(bpy) 3 @MIL-125 photocatalyst presents a remarkably stable and high photoactivity toward the selective oxidative coupling of amines under ambient air with visible light irradiation (λ > 440 nm). The mechanistic investigation unveiled that both effectively photoexcited electrons transfer from [Ru(bpy) 3 ]Cl 2 to MIL-125 and the interaction of C H bonds with superoxide radical (O 2 ·−) play a critical role in photo-catalyzing selective aerobic oxidative coupling of amines. This work highlights a significant role of MOFs as heterogeneous photocatalysts in photocatalytic organic transformations. [ABSTRACT FROM AUTHOR]

This study demonstrated a dye-sensitized TiO 2 -polyoxometalate system (denoted TiO 2 -(PW 12 -TH) 8 , where PW 12 = PW 12 O 40 3− and TH = thionine) for selective oxidation of alcohols under visible light. The results showed that various substituted alcohols were transformed into their corresponding aldehydes with high selectivity. Due to more efficient electrons transfer, large surface area, and enhanced visible light absorption, the photocatalytic activity of TiO 2 -(PW 12 -TH) 8 was superior to any other dye-sensitized system reported to date. The response in the photocurrent-time curves over several on/off cycles of intermittent irradiation showed good reproducibility. The photocurrent response of TiO 2 -(PW 12 -TH) 8 was much higher than that of TiO 2 /TH (physical mixture of TiO 2 and TH), SiO 2 -(PW 12 -TH) 8 or P25-(PW 12 -TH) 8 (P25 = Degussa P25), attributed to the more efficient transfer and longer lifetime of photoexcited electrons. This photocatalytic process confirmed that efficient electron transfer during photocatalytic oxidation plays a vital role in determining the reaction conversion and obtaining good selectivity. Electron paramagnetic resonance (EPR) spectra and radical scavenging experiments proved that superoxide radicals and electrons were the main reactive species in the proposed system, the absence of hydroxyl radicals and holes is demonstrated to be the key of high reaction selectivity. [ABSTRACT FROM AUTHOR]

• Multilayered wrinkled C 3 N 4 nanosheets is obtained via thermal-control synthesis. • The catalyst displays excellent selectivity, recycling stability, long-term durability, notable generality. • Cocatalysis of O 2 − and 1O 2 results in the unprecedented activity in sulfide oxidation. • The electron photoexcitation is valid under the competitive formation of charge carriers and excitons. Incorporating visible light into sulfide oxidation is an emerging desirable strategy to produce versatile sulfoxides. We introduce the design and synthesis of multilayered wrinkled C 3 N 4 nanosheets and demonstrate their unprecedented sulfide oxidation activity. Due to the wrinkled surfaces with a large S BET (208.6 m2g−1), wrinkled C 3 N 4 nanosheets exhibit a sensitive optical response, facilitating the electron photoexcition. Layer structure confinement enables robust e−-h+ interactions and valid photoexcited excitons formation, allowing rapid 1O 2 reactive species production. Integrating the sensitive optical response with robust e−-h+ interactions, photoexcited electrons and excitons are jointly produced, giving large yields of ⋅O 2 − and 1O 2 reactive species that are conductive to O 2 − and 1O 2 cocatalysis with an activity that is up to 33-fold that of bulk C 3 N 4. In the cocatalysis mechanism, both O 2 − and 1O 2 , can produce peroxysulfoxide intermediates, resulting in target sulfoxides. This is the first report on sulfide oxidation via O 2 − and 1O 2 cocatalysis and a promising study on catalyst exploitation for high-efficiency and high-selectivity production process. [ABSTRACT FROM AUTHOR]

The rational design and preparation of low-cost and visible-light-active catalysts for photodegradation of methylene blue (MB) have been regarded as an efficient way for the utilization of solar energy to address the environmental issues. Herein, in this work, a novel MoS 2 /CdS/Bi 2 MoO 6 ternary Z-scheme heterojunction to be applied in pollutant photodegradation is fabricated via hydrothermal method. Under visible light illumination, the as-prepared 2.4% MoS 2 /CdS/Bi 2 MoO 6 -2.0 composites display desirable photocatalytic activity with removal efficiency of 96.0% towards MB and the total organic carbon removal rate of 73.5% within 120 ​min. The apparent reaction rate constant of 2.4% MoS 2 /CdS/Bi 2 MoO 6 -2.0 (0.0256 min−1) is approximately 16 and 5.2 times higher than those of pure Bi 2 MoO 6 (0.0016 min−1) and CdS (0.0049 min−1), respectively. Meanwhile, the as-prepared ternary photocatalyst possess favorable universality. Combined with a series of characterization results, the enhanced photocatalytic activity of 2.4% MoS 2 /CdS/Bi 2 MoO 6 -2.0 is mainly attributed to the successful formation of the ternary Z-scheme photocatalysts, which could boost the separating/transferring efficiency and reduction/oxidation ability of charge carriers. In addition, the cycling experiments demonstrate that 2.4% MoS 2 /CdS/Bi 2 MoO 6 -2.0 possesses favorable stability and recoverability. Overall, this work put forward a simple strategy for synthesizing visible-light-active ternary Z-scheme photocatalytic materials. MoS 2 /CdS/Bi 2 MoO 6 ternary Z-scheme heterojunction has been successfully prepared via hydrothermal method, which exhibit the greatest photocatalytic activity with 96.0% of MB removal efficiency under visible light illumination. [Display omitted] • Preparation of MoS 2 /CdS/Bi 2 MoO 6 Z-scheme heterojunctions via a hydrothermalmethod • MoS 2 /CdS/Bi 2 MoO 6 heterojunctions inhibit the recombination of photogenerated carries. • MoS 2 /CdS/Bi 2 MoO 6 exhibits high photocataltic degradation efficiency. [ABSTRACT FROM AUTHOR]