Rational design and exploration of robust and low‐cost bifunctional oxygen reduction/evolution electrocatalysts are greatly desired for metal–air batteries. Herein, a novel high‐performance oxygen electrode catalyst is developed based on bimetal FeCo nanoparticles encapsulated in in situ grown nitrogen‐doped graphitic carbon nanotubes with bamboo‐like structure. The obtained catalyst exhibits a positive half‐wave potential of 0.92 V (vs the reversible hydrogen electrode, RHE) for oxygen reduction reaction, and a low operating potential of 1.73 V to achieve a 10 mA cm−2 current density for oxygen evolution reaction. The reversible oxygen electrode index is 0.81 V, surpassing that of most highly active bifunctional catalysts reported to date. By combining experimental and simulation studies, a strong synergetic coupling between FeCo alloy and N‐doped carbon nanotubes is proposed in producing a favorable local coordination environment and electronic structure, which affords the pyridinic N‐rich catalyst surface promoting the reversible oxygen reactions. Impressively, the assembled zinc–air batteries using liquid electrolytes and the all‐solid‐state batteries with the synthesized bifunctional catalyst as the air electrode demonstrate superior charging–discharging performance, long lifetime, and high flexibility, holding great potential in practical implementation of new‐generation powerful rechargeable batteries with portable or even wearable characteristic.

Colloidal crystals made of sub-micrometer monodisperse silica or polymer spheres packed in ordered arrays represent a new class of advanced materials that are useful in many areas. For example, they have been used as scaffolds for fabricating highly ordered macroporous materials [1] and as precursors for creating high-strength ceramics.[2] Because of their novel light diffraction and photonic bandgap properties, colloidal crystals are also promising elements in the fabrication of devices such as optical filters and switches, [3] chemical and biochemical sensors, [4] and photonic chips. [5] Various self-assembly techniques based on exploiting gravity sedimentation, [6] electrostatic interaction, [7] and capillary force [8] have been developed to form colloidal crystals on a solid substrate. Although some of these techniques, such as the flow-cell method [9] and vertical deposition, [10] are capable of producing large, single-crystalline domains, for the above-mentioned device applications it is usually necessary to fabricate colloidal crystal films onto substrates with specific microstructures. For this purpose, a large number of templating methods have been combined with the self-assembly of colloidal spheres. For example, Nagayama, Velev, and Yang and their co-workers have demonstrated the use of emulsion droplets as a confined geometry to fabricate free-standing, ordered colloidal sphere aggregates with various shapes, such as spheres, ellipsoids, toroids, and hollow spheres.[11] Wiltzius, Yodh, Whitesides, Ozin, and Xia and their co-workers have used the relief microstructures patterned in substrates as templates to grow colloidal crystals with controllable crystalline orientations, shapes, and sizes.[12] Electrostatic interactions, [13] external electric fields, [14] and wettability [15] have been used to direct the deposition of colloidal spheres over specific regions of planar substrates whose surfaces are pre-patterned into areas differing in charged nature, current density, or wettability. These approaches are usually limited to the formation of concrete assemblies of spheres on substrates, however, generating ordered microstructures between the colloidal crystal film and the substrate, which is important in the fabrication of optical cavities and waveguides for light in a photonic chip,has not yet been well developed. In this paper, we report a method that uses organic liquid patterns as templates to fabricate ordered voids in the colloidal crystal film±substrate system. The original templates, lateral patterns of varying wettability on a substrate, were used to direct the self-organization of an organic liquid [16] under an aqueous colloidal solution of polymer spheres, rather than the self-assembly of colloidal spheres.[15] The self-organized organic liquid patterns on the substrate were stable enough to serve as templates during the deposition process of colloidal spheres and could be removed by spontaneous evaporation after the crystallization was finished, yielding the corresponding ordered ...

Glutathione peroxidase (GPX) is one of the most crucial antioxidant enzymes in a variety of organisms. Here we described a new strategy for generating a novel GPX mimic by combination of a phage-displayed random 15-mer peptide library followed by computer-aided rational design and chemical mutation. The novel GPX mimic is a homodimer consisting of a 15-mer selenopeptide with an appropriate catalytic center, a specific binding site for substrates, and high catalytic efficiency. Its steady state kinetics was also studied, and the values of k cat /K mGSH and k cat / K mH 2 O 2 were found to be similar to that of native GPX and the highest among the existing GPX mimics. Moreover, the novel GPX mimic was confirmed to have a strong antioxidant ability to inhibit lipid peroxidation by measuring the content of malondialdehyde, cell viability, and lactate dehydrogenase activity. Importantly, the novel GPX mimic can penetrate into the cell membrane because of its small molecular size. These characteristics endue the novel mimic with potential perspective for pharmaceutical applications.

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