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For seeking high enantiopurity, the previously reported thermal asymmetric catalysis is usually carried out at low temperature sometimes with limited yield, that is, the high enantiomeric excess (ee) usually at the cost of high yield. Thus, the achieving both high stereoselectivity and yield is an enormous challenge. We report herein two metal nanoparticle (M NP)-loaded and porphyrin-containing homochiral covalent organic framework (CCOF)-based composite catalysts, and their application in the thermally-driven asymmetric one-pot Henry and A 3 -coupling reactions. All the reactions are conducted at elevated temperatures with both excellent stereoselectivity and yield which resulted from the synergy of CCOF confinement effect and M NP catalytic activation. Notably, the needed thermal energy for the asymmetric reactions herein is derived from the photothermal conversion via porphyrin-based CCOF upon irradiation with visible light. Remarkably, the CCOF confinement effect can be effectively maintained up to 100 °C for the asymmetric one-pot Henry and A 3 -coupling reactions herein.

Condensation of benzene-1,3,5-tricarbohydrazide with benzene-1,4-dicarboxaldehyde generated a new covalent organic framework, COF-ASB (1), in which the organic units are held together via hydrazone linkage to form porous frameworks. COF-ASB (1) is highly crystalline and displays good chemical and thermal stability and is permanently porous. In addition, 1 can be an ideal support to load Ru nanoparticles (Ru NPs) to generate Ru@COF-ASB (2). The obtained composite material is able to highly promote one-pot tandem synthesis of imine products from benzyl alcohols and corresponding amines under solvent-free conditions in air.

Porous PtPd NPs with reversed bimetallic structures from Pd-on-Pt to Pt-on-Pd can be one-pot prepared in aqueous solution under the modulation of [C16mim]Cl and glycine and show superior catalytic activities for AB hydrolysis to produce hydrogen.

Rational synthetic design of Sn 4 P 3 -based materials with unique morphological structure and superior sodium storage capability for sodium ion batteries (SIBs) is crucially and urgently needed. In this work, Sn 4 P 3 microspheres encapsulated in hollow carbon spheres (Sn 4 P 3 @C) are prepared by a low temperature phosphorized route using SnO 2 @C as the precursor. The XRD, XPS and TEM results show that multiple Sn 4 P 3 microspheres with a diameter of 200 nm are conformally encapsulated in a hollow carbon shell. This void volume and the elasticity of protective carbon spherical shell can efficiently mitigate volume change of active Sn 4 P 3 microspheres and form the stable solid electrolyte interface film on the surface of the carbon shell during charge/discharge process. When assembled as a negative electrode material into SIBs, the Sn 4 P 3 @C composite shows a stable specific capacity of 420 mAh g −1 after 300 cycles at a current density of 0.2 A g −1 , as well as excellent rate capabilities of 424, 310, 253, 175, 111, 78, and 50 mAh g −1 at the density of 0.2, 0.5, 1, 2, 5, 10, and 20 A g −1 , respectively. More importantly, as-prepared Sn 4 P 3 @C composite shows ultralong cycling performance (after 4000 cycles, at large current densities of 2 and 5 A g −1 , the stable capacities are 205 and 103 mAh g −1 , respectively). It is demonstrated that the Sn 4 P 3 @C composite with the unique morphological design can improve electrochemical cycling performance and rate capability of Sn 4 P 3 . Therefore, it can be expected that our Sn 4 P 3 @C composite is a promising excellent anode material for SIBs. KEYWORDS: Sn 4 P 3 microspheres, hollow carbon spheres, high-rate, anode material, sodium ion battery

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