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The intrinsic properties of nanoscale active materials are always excellent for energy storage devices. However, the accompanying problems of ion/electron transport limitation and active materials shedding of the whole electrodes, especially for high‐loaded electrode composed of nanoparticles with high specific surface area, bring down their comprehensive performance for practical applications. Here, this problem is solved with the as proposed “phase inversion” method, which allows fabrication of tricontinuous structured electrodes via a simple, convenient, low cost, and scalable process. During this process, the binder networks, electron paths, and ion channels can be separately interconnected, which simultaneously achieves excellent binding strength and ion/electron conductivity. This is verified by constructing electrodes with sulfur/carbon (S/C) and Li3V2(PO4)3/C (LVP/C) nanoparticles, separately delivering 869 mA h g−1 at 1 C in Li–S batteries and 100 mA h g−1 at 30 C in Li–LVP batteries, increasing by 26% and 66% compared with the traditional directly drying ones. Electrodes with 7 mg cm−2 sulfur and 11 mg cm−2 LVP can also be easily coated on aluminum foil, with excellent cycling stability. Phase inversion, as a universal method to achieve high‐performance energy storage devices, might open a new area in the development of nanoparticle‐based active materials.

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Herein, Co3O4 nanoparticles/nitrogen-doped carbon (Co3O4/NPC) composites with different structures were prepared via a facile method. Structure control was achieved by the rational morphology design of ZIF-67 precursors, which were then pyrolyzed in air to obtain Co3O4/NPC composites. When applied as catalysts for the oxygen evolution reaction (OER), the M-Co3O4/NPC composites derived from the flower-like ZIF-67 showed superior catalytic activities than those derived from the rhombic dodecahedron and hollow spherical ZIF-67. The former M-Co3O4/NPC composite displayed a small over-potential of 0.3 V, low onset potential of 1.41 V, small Tafel slope of 83 mV dec−1, and a desirable stability. (94.7% OER activity was retained after 10 h.) The excellent performance of the flower-like M-Co3O4/NPC composite in the OER was attributed to its favorable structure. Electronic supplementary materialThe online version of this article (10.1007/s40820-017-0170-4) contains supplementary material, which is available to authorized users.

Aqueous-phase hydrogenation of lactic acid (2-hydroxypropanoic acid) and propionic (propanoic) acid over 5 wt % Ru/C catalyst was performed in a three-phase stirred batch reactor. Kinetic data were collected for reactions at 343−423 K, 3.4−10.3 MPa hydrogen pressure, and 0.05−5 M acid feed concentrations. Adsorption and reaction of individual acids, acid mixtures, and combinations of acids with their alcohol products were investigated to characterize relative hydrogenation rates of the two acids and the extent to which the presence of one species influences the reactivity of another. Mass transfer analysis showed that acid conversion rates were not limited by mass transport resistances over the reaction conditions studied. A two-site Langmuir−Hinshelwood (L−H) kinetic model with a single set of rate and adsorption constants fits the conversion kinetics of both individual and mixed acid hydrogenations. Competitive adsorption of acids and their alcohol products strongly affects hydrogenation rates.

the fact that "the higher unsaturation, the larger merits". These unique properties contribute to the improved electrochemical performance of commercial NCM811/graphite pouch cells up to around 300 cycles with more than 85% capacity retention at 60 °C, along with the LCO cells reaching ≈90% capacity retention over 350 cycles. We hope these findings can provide guidelines for designing functional electrolyte additives for better aggressive battery chemistries.

Flexible solid-state zinc–air batteries (ZABs) with low cost, excellent safety, and high energy density has been considered as one of ideal power sources for portable and wearable electronic devices, while their practical applications are still hindered by the kinetically sluggish cathodic oxygen reduction and oxygen evolution reactions (ORR/OER). Herein, a Janus-structured flexible free-standing bifunctional oxygen electrocatalyst, with OER-active O, N co-coordinated Ni single atoms and ORR-active Co3O4@Co1–x S nanosheet arrays being separately integrated at the inner and outer walls of flexible hollow carbon nanofibers (Ni-SAs/HCNFs/Co-NAs), is reported. Benefiting from the sophisticated topological structure and atomic-level-designed chemical compositions, Ni-SAs/HCNFs/Co-NAs exhibits outstanding bifunctional catalytic activity with the ΔE index of 0.65 V, representing the current state-of-the-art flexible free-standing bifunctional ORR/OER electrocatalyst. Impressively, the Ni-SAs/HCNFs/Co-NAs-based liquid ZAB show a high open-circuit potential (1.45 V), high capacity (808 mAh g–1 Zn), and extremely long life (over 200 h at 10 mA cm–2), and the assembled flexible all-solid-state ZABs have excellent cycle stability (over 80 h). This work provides an efficient strategy for developing high-performance bifunctional ORR/OER electrocatalysts for commercial applications.

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