The implementation of synthetic polymer membranes in gas separations, ranging from natural gas sweetening, hydrogen separation, helium recovery, carbon capture, oxygen/nitrogen enrichment, etc., has stimulated the vigorous development of high-performance membrane materials. However, size-sieving types of synthetic polymer membranes are frequently subject to a trade-off between permeability and selectivity, primarily due to the lack of ability to boost fractional free volume while simultaneously controlling the micropore size distribution. Herein, we review recent research progress on microporosity manipulation in high-free-volume polymeric gas separation membranes and their gas separation performance, with an emphasis on membranes with hourglass-shaped or bimodally distributed microcavities. State-of-the-art strategies to construct tailorable and hierarchically microporous structures, microporosity characterization, and microcavity architecture that govern gas separation performance are systematically summarized.

Si anode is of paramount importance for advanced energy-dense lithium-ion batteries (LIBs). However, the large volume change as well as stress generates during its lithiation-delithiation process poses a great challenge to the long-term cycling and hindering its application. Herein this work, a composite binder is prepared with a soft component, guar gum (GG), and a rigid linear polymer, anionic polyacrylamide (APAM). Rich hydroxy, carboxyl, and amide groups on the polymer chains not only enable intermolecular crosslinking to form a web-like binder, A2G1, but also realize strong chemical binding as well as physical encapsulating to Si particles. The resultant electrode shows limited thickness change of merely 9% on lithiation and almost recovers its original thickness on delithiation. It demonstrates high reversible capacity of 2104.3 mAh g⁻¹ after 100 cycles at a current density of 1800 mA g⁻¹, and in constant capacity (1000 mAh g⁻¹) test, it also shows a long life of 392 cycles. Therefore, this soft-hard combining web-like binder illustrates its great potential in the future applications.

The key to realize long-life high energy density lithium batteries is to exploit functional electrolytes capable of stabilizing both high voltage cathode and lithium anode. The emergence of localized high-concentration electrolytes (LHCEs) shows great promise for ameliorating the above-mentioned interfacial issues. In this work, a lithium difluoro(oxalate)borate (LiDFOB) based nonflammable dual-anion LHCE is designed and prepared. Dissolving in the mixture of trimethyl phosphate (TMP) /1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropylether (D₂), the continuously consumption of LiDFOB is suppressed by simply introducing lithium nitrate (LiNO₃). Meantime, as most of the TMP molecular are coordinated with Li⁺, the electrolyte does not show incompatibility issue between neither metal lithium nor graphite anode. Therefore, it demonstrates excellent capability in stabilizing the interface of Ni-rich cathode and regulating lithium deposition morphology. The Li||LiNi_0.87Co_0.08Mn_0.05O₂ (NCM87) batteries exhibit high capacity retention of more than 90% after 200 cycles even under the high cutoff voltage of 4.5 V, 1 C rate. This study offers a prospective method to develop safe electrolytes suitable for high voltage applications, thus providing higher energy densities.

Single-component anode materials can barely satisfy the growing demand for next-generation Li-ion batteries with higher capacity and cyclability. Thus developing multi-component synergistic electrodes has become a critical issue. Herein, inspired by natural corn, a ternary hierarchical self-supported array design is proposed. Based on a sequential transformation route, Si/C-modified Co₃O₄ nanowire arrays are constructed on 3D Ni foams to form a binder-free integrated electrode. Specifically, an ionic liquid-assisted electrodeposition strategy is employed to prepare discrete ultrafine Si nanoparticles on nanoscale array substrates, which follow the Volmer–Weber island growth mode. In this corn-mimetic system, kernel-like Si nanoparticles and a husk-like carbon coating layer function as enhancing and protecting units, respectively, to improve the capacity and stability of the cobalt oxide basic unit. Taking advantage of a synergistic effect, the ternary nanoarray anode achieves a significant performance enhancement compared to pristine Co₃O₄, showing a special capacity as high as ~1, 000 mAh·g⁻¹ at 100 mA·g⁻¹. By extending this corn-mimetic hierarchical array design to other basic, enhancing, and protecting units, new ideas for constructing synergistic nano-architectures for energy conversion and storage field are developed.