Search

Zinc ion batteries (ZIBs) encounter interface issues stemming from the water‐rich electrical double layer (EDL) and unstable solid‐electrolyte interphase (SEI). Herein, we propose the dynamic EDL and self‐repairing hybrid SEI for practical ZIBs via incorporating the horizontally‐oriented dual‐site additive. The rearrangement of distribution and molecular configuration of additive constructs the robust dynamic EDL under different interface charges. And, a self‐repairing organic–inorganic hybrid SEI is constructed via the electrochemical decomposition of additive. The dynamic EDL and self‐repairing SEI accelerate interfacial kinetics, regulate deposition and suppress side reactions in the both stripping and plating during long‐term cycles, which affords high reversibility for 500 h at 42.7 % depth of discharge or 50 mA ⋅ cm−1. Remarkably, Zn//NVO full cells deliver the impressive cycling stability for 10000 cycles with 100 % capacity retention at 3 A ⋅ g−1 and for over 3000 cycles even at lean electrolyte (7.5 μL ⋅ mAh−1) and high loading (15.26 mg ⋅ cm−2). Moreover, effectiveness of this strategy is further demonstrated in the low‐temperature full cell (−30 °C). [ABSTRACT FROM AUTHOR]

In situ construction of solid electrolyte interfaces (SEI) is an effective strategy to enhance the reversibility of zinc (Zn) anodes. However, in situ SEI to afford high reversibility under high current density conditions (≥20 mA cm−2) is highly desired yet extremely challenging. Herein, we propose a dual reaction strategy of spontaneous electrostatic reaction and electrochemical decomposition for the in situ construction of SEI, which is composed of organic‐rich upper layer and inorganic‐rich inner layer. Particularly, in situ SEI performs as "growth binder" at small current density and "orientation regulator" at high current density, which significantly suppresses side reactions and dendrite growth. The in situ SEI affords the record‐breaking reversibility of Zn anode under practical conditions, Zn//Zn symmetric cells can stably cycle for over 1300 h and 400 h at current densities of 50 mA cm−2 and 100 mA cm−2, respectively, showcasing an exceptional cumulative capacity of 67.5 Ah cm−2. Furthermore, the practicality of this in situ SEI is verified in Zn//PANI pouch cells with high mass loading of 25.48 mg cm−2. This work provides a universal strategy to design advanced SEI for practical Zn‐ion batteries. [ABSTRACT FROM AUTHOR]

Flexible zinc‐air batteries are leading power sources for next‐generation smart wearable electronics. However, flexible zinc‐air batteries suffer from the highly‐corrosive safety risk and limited lifespan due to the absence of reliable solid‐state electrolytes (SSEs). Herein, a single‐anion conductive SSE with high‐safety is constructed by incorporating a highly amorphous dual‐cation ionomer into a robust hybrid matrix of functional carbon nanotubes and polyacrylamide polymer. The as‐fabricated SSE obtains dual‐penetrating ionomer‐polymer networks and hierarchical ionic highways, which contribute to mechanical robustness with 1200 % stretchability, decent water uptake and retention, and superhigh ion conductivity of 245 mS ⋅ cm−1 and good Zn anode reversibility. Remarkably, the flexible solid‐state zinc‐air batteries delivers a high specific capacity of 764 mAh ⋅ g−1 and peak power density of 152 mW ⋅ cm−2 as well as sustains excellent cycling stability for 1050 cycles (350 hours). This work offers a new paradigm of OH− conductors and broadens the definition and scope of OH− conductors. [ABSTRACT FROM AUTHOR]

Porous organic polymers (POPs) with high porosity and tunable functionalities have been widely studied for use in gas separation, catalysis, energy conversion and energy storage. However, the high cost of organic monomers, and the use of toxic solvents and high temperatures during synthesis pose obstacles for large‐scale production. Herein, we report the synthesis of imine and aminal‐linked POPs using inexpensive diamine and dialdehyde monomers in green solvents. Theoretical calculations and control experiments show that using meta‐diamines is crucial for forming aminal linkages and branching porous networks from [2+2] polycondensation reactions. The method demonstrates good generality in that 6 POPs were successfully synthesized from different monomers. Additionally, we scaled up the synthesis in ethanol at room temperature, resulting in the production of POPs in sub‐kilogram quantities at a relatively low cost. Proof‐of‐concept studies demonstrate that the POPs can be used as high‐performance sorbents for CO2 separation and as porous substrates for efficient heterogeneous catalysis. This method provides an environmentally friendly and cost‐effective approach for large‐scale synthesis of various POPs. [ABSTRACT FROM AUTHOR]

DNA is a true polymer that stores the genetic information of an organism. With its amazing biological and polymeric characteristics, DNA has been regarded as a universal building block for the construction of diverse materials for real‐world applications. Through various approaches including ligation, polymerization, chemical crosslinking, and physical crosslinking, both pure and hybrid DNA gels have been developed as generic materials. This Review discusses recent advances in the construction of DNA‐based networks without considering any of DNA′s genetic properties. In addition, we highlight the biomedical and non‐biomedical applications of DNA as generic materials. Owing to the superb molecular recognition, self‐assembly, and responsiveness of DNA, a mushrooming number of DNA materials with various properties have been developed for general utilization. [ABSTRACT FROM AUTHOR]

Lithium‐sulfur (Li‐S) batteries are regarded as a promising next‐generation system for advanced energy storage owing to a high theoretical energy density of 2600 Wh kg−1. However, the practical implementation of Li‐S batteries has been thwarted by the detrimental shuttling behavior of polysulfides, and the sluggish kinetics in electrochemical processes. Herein, a novel single atom (SA) catalyst with oversaturated Fe‐N5 coordination structure (Fe‐N5‐C) is precisely synthesized by an absorption–pyrolysis strategy and introduced as an effective sulfur host material. The experimental characterizations and theoretical calculations reveal synergism between atomically dispersed Fe‐N5 active sites and the unique carbon support. The results exhibit that the sulfur composite cathode built on the Fe‐N5‐C can not only adsorb polysulfides via chemical interaction, but also boost the redox reaction kinetics, thus mitigating the shuttle effect. Meanwhile, the robust three‐dimensional nitrogen doped carbon nanofiber with large surface area, and high porosity enables strong physical confinement and fast electron/ion transfer process. Attributed to such unique features, Li‐S batteries with S/Fe‐N5‐C composite cathode realize outstanding cyclability and rate capability, as well as high areal capacities under raised sulfur loading, which demonstrates great potential in developing advanced Li‐S batteries. [ABSTRACT FROM AUTHOR]

Efficient coupling solar energy conversion and N2 fixation by photocatalysis has been shown promising potentials. However, the unsatisfied yield rate of NH3 curbs its forward application. Defective typical perovskite, BaTiO3, shows remarkable activity under an applied magnetic field for photocatalytic N2 fixation with an NH3 yield rate exceeding 1.93 mg L−1 h−1. Through steered surface spin states and oxygen vacancies, the electromagnetic synergistic effect between the internal electric field and an external magnetic field is stimulated. X‐ray absorption spectroscopy and density functional theory calculations reveal the regulation of electronic and magnetic properties through manipulation of oxygen vacancies and inducement of Lorentz force and spin selectivity effect. The electromagnetic effect suppresses the recombination of photoexcited carriers in semiconducting nanomaterials, which acts synergistically to promote N2 adsorption and activation while facilitating fast charge separation under UV‐vis irradiation. [ABSTRACT FROM AUTHOR]

Soft organisms such as earthworms can access confined, narrow spaces, inspiring scientists to fabricate soft robots for in vivo manipulation of cells or tissues and minimally invasive surgery. We report a super‐soft and super‐elastic magnetic DNA hydrogel‐based soft robot (DNA robot), which presents a shape‐adaptive property and enables magnetically driven navigational locomotion in confined and unstructured space. The DNA hydrogel is designed with a combinational dynamic and permanent crosslinking network through chain entanglement and DNA hybridization, resulting in shear‐thinning and cyclic strain properties. DNA robot completes a series of complex magnetically driven navigational locomotion such as passing through narrow channels and pipes, entering grooves and itinerating in a maze by adapting and recovering its shape. DNA robot successfully works as a vehicle to deliver cells in confined space by virtue of the 3D porous networked structure and great biocompatibility. [ABSTRACT FROM AUTHOR]

The multiparametric nature of nanoparticle self-assembly makes it challenging to circumvent the instabilities that lead to aggregation and achieve crystallization under extreme conditions. By using non-base-pairing DNA as a model ligand instead of the typical base-pairing design for programmability, long-range 2D DNA-gold nanoparticle crystals can be obtained at extremely high salt concentrations and in a divalent salt environment. The interparticle spacings in these 2D nanoparticle crystals can be engineered and further tuned based on an empirical model incorporating the parameters of ligand length and ionic strength. [ABSTRACT FROM AUTHOR]