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The instability of zinc metal anode caused by zinc dendrite growth and severe parasitic reactions has significantly restricted the extensive application of rechargeable aqueous zinc-ion batteries (RAZBs). Herein, based on the strategy of dynamic hard domains, we develop an ion-conductive supramolecular elastomer consisting of Zn salts and the polyurethane-urea-polypropylene glycol polymer skeleton. This elastomer combines high mechanical strength, high ionic conductivity, decent hydrophobicity, and high adhesion to stabilize the electrode–electrolyte interface. In the elastomer system, this elastomer can dynamically adapt to the volume changes of Zn anodes during repeated zinc plating/stripping processes through the reversible dissociation/reassociation of hierarchical hydrogen bonds (H-bonds) formed by the polar groups of urea and urethane moieties. Meanwhile, the coordination of Zn2+with soft polypropylene glycol (PPG) segments contributes to fast ion transport. This hydrophobic elastomer can also effectively inhibit water-induced corrosion by shielding the active Zn metal from the aqueous electrolyte. Based on the above synergies, the surface-modified anode shows excellent cycling stability above 550 h at a high current density of 5 mA cm–2and a capacity of 2.5 mAh cm–2. Moreover, the assembled Zn//MnO2full cell also displayed an enhanced electrochemical performance. This work provides inspiration for the design of solid electrolyte interphase (SEI) layers in aqueous battery chemistry to accelerate the application of RAZBs.

The heterogeneity and continuous cracking of the static solid electrolyte interphase (SEI) are one of the most critical barriers that largely limit the cycle life of lithium (Li) metal batteries. Herein, we report a fatigue-free dynamic supramolecular ion-conductive elastomeric interphase (DSIEI) for a highly efficient and dendrite-free lithium metal anode. The soft phase poly(propylene glycol) backbone with loosely Li+–O coordinating interaction was responsible for fast ion transport. Simultaneously, the supramolecular quadruple hydrogen bonds (H-bonds) in the hard phases endow the elastomeric interphase with mechanical enhancement, while gradient H-bonds can dissipate strain energy via the sequential bonding cleavage. Such a design affords superior mechanical robustness, high ionic conductivity, gradient energy dissipation, and high Li+transference number. Besides, anion enrichment in DSIEI assists in situ construction of a lithium fluoride-rich inner layer upon cycling. The resultant biomimetic bilayer structure enables the symmetric cells with superior cyclability of over 600 h at a high current density of 10 mA cm–2. Moreover, the DSIEI allows stable operation of the full cells under constrained conditions of limited lithium excess, a high-loading LiNi0.8Co0.1Mn0.1O2cathode, and a low negative/positive capacity (N/P) ratio. This work presents a powerful strategy for deigning artificial SEI and achieving high-energy-density Li metal batteries.

Aqueous zinc batteries are considered as a viable candidate for cost-effective and environmentally sustainable energy storage technology but are severely hampered by the notorious dendrite growth and parasitic reactions at the zinc anode side. Herein, we propose a bifunctional colloidal electrolyte design that utilizes upconversion nanocrystals, i.e., NaErF4@NaYF4, as a solid additive to provide the sustained release of functional metal and fluoride ions, which can effectively improve the reversibility of the Zn anode to inhibit dendrite growth and hydrogen evolution through forming an electrostatic shielding layer and in situ constructing a ZnF2-enriched protective interface. Experimental characterization and molecular dynamics simulation jointly confirm that the NaErF4@NaYF4additive could modify the Zn2+solvation environment in the vicinity of the NaErF4@NaYF4surface via the strong electrostatic coupling with Zn2+ions. As a consequence, the modified electrolyte enables stable zinc plating/stripping over 2100 h at a current density of 3 mA cm–2and a capacity of 1 mAh cm–2in symmetric cells. The assembled Zn||MnO2full cells with a modified electrolyte can operate stably for 1600 cycles at 2 A g–1. This work thereby has great potential for the exploration of multifunctional electrolyte additives toward long-lasting aqueous Zn metal batteries.

We utilize numerical simulations based on the discrete dipole approximation to study the effects of surface-stress-driven lattice contraction on the extinction spectra of silver nanowires with a square cross section of length 2 nm. The novel finding of the present work is the determination that the blue shift that is induced in the silver nanowires due to surface-stress-driven lattice contraction increases with an increase in the nanowire aspect ratio; the blue shift in the longitudinal plasmon resonance wavelength reaches 20 nm in air and 30 nm in water when the nanowire aspect ratio increases to six. Furthermore, we have delineated the lattice contraction effects on the relative contributions of the free (conduction) electrons and the ionic core (bound) electrons to the observed blue shift; specifically, due to the increasingly free electron optical response of the nanowires with increasing aspect ratio, the blue shift due to the contraction-driven increase in the free electron density is found to dominate the red shift due to the increase in the core electron density for larger nanowire aspect ratios. The results collectively indicate that surface-stress-driven lattice contraction plays an important role in blue shifting the longitudinal plasmon resonance wavelength for ultrasmall silver nanowires.

In recent years, Content‐Centric Networking (CCN) has been considered as a novel promising paradigm for the future Internet, shifting from provider‐driven end‐to‐end communication mode to interest‐driven content retrieval communication one, which greatly depends on routing technology. In spite of this, CCN routing always faces two significant issues, ie, scalability and large‐scale deployment, which restrict the increasing development of CCN but can be addressed by introducing the ideas of Software‐Defined Networking (SDN) and community (domain) division. However, the current routing proposals on the integrating with SDN, community division or their combination, still have some limitations to be improved. Therefore, in this paper, we propose a novel and intelligent CCN Routing mechanism based on SDN and Community Division (CRSCD). At first, a community division scheme based on eigenvetor centrality and label propagation is proposed to help content retrieval. Then, for each divided community, we deploy an SDN controller which consists of two tables, ie, content index and community topology to help manage the global network view. Finally, a comprehensive routing mechanism including intracommunity routing based on Ant Colony Optimization (ACO) and intercommunity routing based on interaction frequency is devised. The proposed CRSCD is implemented over Cogent topology, and the experimental results demonstrate that the introduction of SDN and community division can accelerate content retrieval greatly and has better performance than the previous work. The proposed CRSCD consists of three kernel modules, i.e., community division, SDN management, and routing decision. Among them, the first one is for dividing CCN mesh topology into some communities according to eigenvector centrality and label propagation; the second one selects a node from each community and assigns an SDN controller at this node according to node competitiveness; the last one designs a routing mechanism based on ACO with the help of CIT and CTT.