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The development of solar-driven organic synthesis processes as an alternative to conventional thermo-catalytic technologies is of great research significance in academia and industry. Herein, we looked into the photoinduced Baeyer−Villiger oxidation of cyclohexanone based on the Mukaiyama method for the first time. We fabricated a crystalline polyoxometalate-based metal−organic framework photocatalyst, CR-SiW 12 , which represents the first example of trinuclear ruthenium clusters involved in the construction of polyoxometalate-based metal−organic frameworks. The cyclohexanone was efficiently converted to ε-caprolactone under visible light (>400 nm) irradiation with CR-SiW 12 as the catalyst, with a reaction turnover number and turnover frequency recorded as 941 and 274.5 h −1 , respectively, and the apparent quantum yield at 465 nm was measured to be 8.4%. Moreover, CR-SiW 12 exhibited high structural stability and reaction reusability where reaction yield remained high at 91.3% after five consecutive reaction cycles. This work offers a promising strategy for accomplishing Baeyer−Villiger oxidation reactions under green conditions.

The development of visible-light-responsive, environmentally friendly, and reusable photocatalysts for organic oxidation reactions is of vital significance. Herein, four polyoxometalate-based metal−organic frameworks (POMOFs) were synthesized and systematically characterized by assembling the paddlewheel complex Rh 2 (OAc) 4 and various polyoxometalates (POMs). Single-crystal X-ray diffraction analysis revealed that the four POMOFs were isomorphic and possessed rare structural features among the POMOFs, with POMs as nodes and Rh 2 (OAc) 4 as linkers. As expected, the activities of the four POMOFs for the photocatalytic oxidative coupling of benzylamine were better than that of Rh 2 (OAc) 4 or POMs individually, which was ascribed to the synergistic effect between them, and the intrinsic reasons for the difference in the activity were explained via electrochemical measurements. In particular, the product imine yield reached 96.1% with NaRh-SiW 12 as the catalyst and a turnover number and a turnover frequency of 480.5 and 120.5 h −1 , respectively, while the product yield remained as high as 92% after three repetitions, evidencing its high stability. Moreover, the higher activities of the four POMOFs for the selective epoxidation of various alkenes reaffirm the synergistic effect between Rh 2 (OAc) 4 and POMs.

A high-voltage LiNi0.5Mn1.5O4 (LNMO) cathode was modified by Li2ZrO3 (LZO), a fast ion conductor with a unique core–shell crystalline-amorphous structure. The electrochemical results indicated a greatly improved capacity retention for LNMO-1LZO compared to LNMO. Moreover, the rate performance (100 mAh·g−1) of LNMO-1LZO at a high current density of 10 C was superior to those of pristine LNMO and other modified samples. The enhanced electrochemical performance was ascribed to the generation of dual-phase island-shaped LZO with an interior crystalline phase, which accelerated Li+ diffusion, and an exterior amorphous shell, which enhanced interfacial compatibility and stability without influencing the intrinsic spinel structure of bulk LNMO. Thus, modification with this hybrid material has the remarkable synergetic effect of enhancing interfacial Li+ diffusion and stabilizing the interfacial structure during cycling.

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