A facile and binder-free method is developed for the in-situ and horizontal growth of ultrathin mesoporous Co 3 O 4 layers on the surface of carbon fibers in the carbon cloth (ultrathin Co 3 O 4 /CC) as high-performance air electrode for the flexible Zn-air battery. In particular, the ultrathin Co 3 O 4 layers have a maximum contact area on the conductive support, facilitating the rapid electron transport and preventing the aggregation of ultrathin layers. The ultrathin feature of Co 3 O 4 layers is characterized by the transmission electron microscopy, Raman spectra and X-ray absorption fine structure spectroscopy. Benefiting from the high utilization degree of active materials and rapid charge transport, the mass activity for oxygen reduction and evolution reactions of the ultrathin Co 3 O 4 /CC electrode is more than 10 times higher than that of the carbon cloth loaded with commercial Co 3 O 4 nanoparticles. Compared to the commercial Co 3 O 4 /CC electrode, the flexible Znair battery using ultrathin Co 3 O 4 /CC electrode exhibits excellent rechargeable performance and high mechanical stability. Furthermore, the flexible Zn-air battery was integrated with a flexible display This article is protected by copyright. All rights reserved.3unit. The whole integrated device can operate without obvious performance degradation under serious deformation and even during the cutting process, which makes it highly promising for wearable and roll-up optoelectronics.

Directly harvesting solar energy for battery charging represents an ultimate solution toward low-cost, green, efficient and sustainable electrochemical energy storage. Here, we design a sunlight promotion strategy into rechargeable zinc–air battery with significantly reduced charging potential below the theoretical cell voltage of zinc–air batteries. The sunlight-promoted zinc–air battery using BiVO4 or α-Fe2O3 air photoelectrode achieves a record-low charge potential of ~1.20 and ~1.43 V, respectively, under illumination, which is lowered by ~0.5–0.8 V compared to the typical charge voltage of ~2 V in conventional zinc–air battery. The band structure and photoelectrochemical stability of photoelectrodes are found to be key factors determining the charging performance of sunlight-promoted zinc–air batteries. The introduction of photoelectrode as an air electrode opens a facile way for developing integrated single-unit zinc–air batteries that can efficiently use solar energy to overcome the high charging overpotential of conventional zinc–air batteries.

Chiral nanoporous metal-organic frameworks are constructed by using dicarboxyl-functionalized chiral Ni(salen) and Co(salen) ligands. The Co(salen)-based framework is shown to be an efficient and recyclable heterogeneous catalyst for hydrolytic kinetic resolution (HKR) of racemic epoxides with up to 99.5% ee. The MOF structure brings Co(salen) units into a highly dense arrangement and close proximity that enhances bimetallic cooperative interactions, leading to improved catalytic activity and enantioselectivity in HKR compared with its homogeneous analogues, especially at low catalyst/substrate ratios.

Two-dimensional (2D) materials with highly ordered in-plane nanopores are crucial for numerous applications, but their rational synthesis and local structural characterization remain two grand challenges. We illustrate here that singlecrystalline ultrathin 2D MOF nanosheets (MONs) with intrinsic porosity can be prepared by exfoliating layered metal−organic frameworks (MOFs), whose layers are stabilized by sterically bulky groups. As a result, three three-dimensional (3D) isostructural lanthanide MOFs possessing porous layer structures are constructed by coordinating metal ions with an angular dicarboxylate linker derived from chiral 1,1′-biphenyl phosphoric acid with pendant mesityl groups. The Eu-MOF is readily ultrasonic exfoliated into single-crystalline nanosheets with a thickness of ca. 6.0 nm (2 layers) and a lateral size of 1.5 × 3.0 μm 2 . The detailed structural information, i.e., the pore channels and individual organic and inorganic building units in the framework, is clearly visualized by a low-dose high-resolution transmission electron microscopy (HRTEM) technique. Benefiting from their ultrathin feature, the nanosheets are well embedded into the polymer matrix to form free-standing mixed-matrix membranes. In both the solution and membrane phase, the fluorescence of the MONs can be effectively quenched by a total of 17 chiral terpenes and terpenoids through supramolecular interactions with uncoordinated chiral phosphoric acids, leading to a chiral optical sensor for detecting vapor enantiomers, which is among the most challenging molecular recognition tasks.

The design and development of robust and porous supported catalysts with high activity and selectivity is extremely significant but very challenging for eco-friendly synthesis of fine chemicals and pharmaceuticals. We report here the design and synthesis of highly stable chiral Zr­(IV)-based MOFs with different topologies to support Ir complexes and demonstrate their network structures-dependent asymmetric catalytic performance. Guided by the modulated synthesis and isoreticular expansion strategy, five chiral Zr-MOFs with a flu or ith topology are constructed from enantiopure 1,1′-biphenol-derived tetracarboxylate linkers and Zr6, Zr9, or Zr12 clusters. The obtained MOFs all show high chemical stability in boiling water, strongly acidic, and weakly basic aqueous solutions. The two flu MOFs featuring the dihydroxyl groups of biphenol in open and large cages, after sequential postsynthetic modification with P­(NMe2)3 and [Ir­(COD)­Cl]2, can be highly efficient and recyclable heterogeneous catalysts for hydrogenation of α-dehydroamino acid esters with up to 98% ee, whereas the three ith MOFs featuring the dihydroxyl groups in small cages cannot be installed with P­(NMe2)3 to support the Ir complex. Incorporation of Ir-phosphorus catalysts into Zr-MOFs leads to great enhancement of their chemical stability, durability, and even stereoselectivity. This work therefore not only advances Zr-MOFs as stable supports for labile metal catalysts for heterogeneous asymmetric catalysis but also provides a new insight into how highly active chiral centers can result due to the framework topology.

Pt-Decorated highly porous flower-like Ni particles with nanopores and well-dispersed small Pt grains on petals show high activity for ammonia electro-oxidation.

Chiral porous metal-metallosalan frameworks are constructed from an unsymmetrical chiral pyridinecarboxylate ligand derived from Ti(salan) and are shown to be heterogeneous catalysts for asymmetric oxidation of thioethers to sulfoxides.

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