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Vanadium‐based materials are considered promising cathodes for high‐energy‐density zinc‐ion batteries (ZIBs) owing to their open skeleton structure and multielectron redox reactions. However, most vanadium‐based materials have low intrinsic conductivities and sluggish reaction kinetics, resulting in poor cycling properties. Herein, a layer‐stacked MnxV2O6+V2CTx (MVO+V2C) heterostructure cathode with high capacity and superior cyclic stability based on an electrostatic self‐assembly strategy is proposed. The abundant heterointerfaces between MVO and V2C dramatically enhanced the intrinsic conductivity of the composites. Moreover, the generation of built‐in electric fields at the layer‐stacked MVO/V2C heterointerface reduced the migration energy barrier of Zn2+, accelerated charge carrier transport, and enhanced the reaction kinetics of the cathode. In addition, the abundance of nano‐channels in the heterostructures facilitates rapid electrolyte transport in composites. Therefore, the MVO+V2C cathode showed a capacity of 389.4 mAh g−1 after 590 cycles at 0.5 A g−1 and 290.2 mAh g−1 after 6000 cycles at 5 A g−1, demonstrating its superior cycling stability. In particular, the assembled MVO+V2C batteries exhibited remarkable electrochemical performance at −20–40 °C, revealing its excellent wide‐temperature adaptability. This work offers important insights into the design of cathode materials for long‐lifespan and wide‐temperature ZIBs. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries are regarded as the promising candidates for large‐scale energy storage systems owing to low cost and high safety; however, their applications are restricted by their poor low‐temperature performance. Herein, a low‐temperature electrolyte for low‐temperature aqueous zinc‐ion batteries is designed by introducing low‐polarity diglyme into an aqueous solution of Zn(ClO4)2. The diglyme disrupts the hydrogen‐bonding network of water and lowers the freezing point of the electrolyte to −105 °C. The designed electrolyte achieves ionic conductivity up to 16.18 mS cm−1 at −45 °C. The diglyme and ClO4− reconfigure the solvated structure of Zn2+, which is more favorable for the desolvation of Zn2+ at low temperatures. In addition, the diglyme effectively suppresses the dendrites, hydrogen evolution reaction, and by‐products of the zinc anode, improving the cycle stability of the battery. At −20 °C, a Zn||Zn symmetrical cell is cycled for 5200 h at 1 mA cm−2 and 1 mA h cm−2, and a Zn||polyaniline battery achieves an ultra‐long cycle life of 10 000 times. This study sheds light on the future design of electrolytes with high ionic conductivity and easy desolvation at low temperatures for rechargeable batteries. [ABSTRACT FROM AUTHOR]

Although stem cell therapy holds promise for the treatment of spinal cord injury (SCI), its practical applications are limited by the low degree of neural differentiation. Electrical stimulation is one of the most effective ways to promote the differentiation of stem cells into neurons, but conventional wired electrical stimulation may cause secondary injuries, inflammation, pain, and infection. Here, based on the high conductivity of graphite and the electromagnetic induction effect, graphite nanosheets with neural stem cells (NSCs) are proposed as an electromagnetic cellularized patch to generate in situ wirelessly pulsed electric signals under a rotating magnetic field for regulating neuronal differentiation of NSCs to treat SCI. The strength and frequency of the induced voltage can be controlled by adjusting the rotation speed of the magnetic field. The generated pulsed electrical signals promote the differentiation of NSCs into functional mature neurons and increase the proportion of neurons from 12.5% to 33.7%. When implanted in the subarachnoid region of the injured spinal cord, the electromagnetic cellularized patch improves the behavioral performance of the hind limbs and the repair of spinal cord tissue in SCI mice. This work opens a new avenue for remote treatment of SCI and other nervous system diseases. [ABSTRACT FROM AUTHOR]

The hazard-free treatment of Cr(vi) ions is critical in modern industry. Photocatalytic reduction and detoxification are high-potential strategies. Photocatalysts with high efficiency, low cost, environmental friendliness, and easy mass products are required. In this study, we report a facile strategy using triethanolamine (TEOA) as a capping ligand to modify the surface of ZnO nanospheres. The experimental and theoretical results reveal that the presence of TEOA on the surface was beneficial for electron enrichment on Zn and hole transfer to TEOA and can photocatalytically reduce Cr(vi) by almost 100% in 5 min. The photocatalytic property of TEOA-modified ZnO could be renewed by the reabsorption of TEOA in solution. The great sedimental properties benefit photocatalyst recycling and renewal, which also provides high potential for water pollution and environmental emergency responses applications.

Descriptors play a crucial role in electrocatalysis as they can provide valuable insights into the electrochemical performance of energy conversion and storage processes. They allow for the understanding of different catalytic activities and enable the prediction of better catalysts without relying on the time-consuming trial-and-error approaches. Hence, this comprehensive review focuses on highlighting the significant advancements in commonly used descriptors for critical electrocatalytic reactions. First, the fundamental reaction processes and key intermediates involved in several electrocatalytic reactions are summarized. Subsequently, three types of descriptors are classified and introduced based on different reactions and catalysts. These include d-band center descriptors, readily accessible intrinsic property descriptors, and spin-related descriptors, all of which contribute to a profound understanding of catalytic behavior. Furthermore, multi-type descriptors that collectively determine the catalytic performance are also summarized. Finally, we discuss the future of descriptors, envisioning their potential to integrate multiple factors, broaden application scopes, and synergize with artificial intelligence for more efficient catalyst design and discovery. [ABSTRACT FROM AUTHOR]

Orbital degree of freedom plays a crucial role in governing the physical and chemical properties of solid materials, and it is widely investigated in the fields of physics, material science, and chemistry. Typically, orbital‐energy‐related scenarios, such as d‐band center or electron occupancy, have been discussed in the catalytic materials, since they can control the surface‐adsorbate bonding strength to modulate the catalytic activity. However, the impact of orbital morphology, that is the "posture" of orbitals on catalysts' surfaces, has never been studied. Here the importance of 3d‐orbital morphology on the activity of oxygen reduction reaction (ORR) in a strongly correlated oxide α‐Ti2O3 is highlighted. Superior ORR performance is observed in α‐Ti2O3 (Ti3+:3d1) than that of the anatase and rutile TiO2 (Ti4+:3d0), with higher Faradaic efficiency (87.3%) and H2O2 selectivity (93.2%). More importantly, a novel orbital‐morphology‐based mechanism is developed and the orbital morphology dominates the catalytic activity by determining the surface‐adsorbates d–p orbital hybridization via orbitals' overlap, resulting in a crystal‐plane‐dependent ORR activity in α‐Ti2O3. The work reveals the strong interplay between the orbital morphology, d–p hybridization, and ORR activity, which broadens the fundamental understanding of catalysts from a new view of the orbital degree of freedom. [ABSTRACT FROM AUTHOR]

Lithium metal‐graphene host composite is a promising anode material for high‐energy‐density Li battery owing to its three‐dimensional structure, micro‐level controllable thickness and ultrahigh specific capacity. However, we discover that the hydroxyl/carboxyl functional groups in the reduced graphene oxide (rGO) host are likely to be reduced into lithium carbonate composition in the solid‐electrolyte interphase (SEI), which resulted in severe lithium dendrite growth that deteriorate its electrochemical performances. Here, we develop a magnesium anchoring strategy that selectively bond the Mg ion with the hydroxyl/carboxyl groups in rGO host, generating an electrolyte‐derived lithium fluoride‐dominant SEI instead of oxygen groups‐derived, lithium carbonate‐dominant SEI. By anchoring 0.60% of Mg in the rGO host using a facile compositing‐pyrolysis approach, Li dendrite growth in anode can be significantly suppressed, and the cycling stability of Li metal full cells can be prolonged by 200%. These findings give new insight into the mechanism of SEI formation in Li metal anode, and provide a new design strategy for restraining the reduced reaction of hydroxyl/carboxyl groups in graphene to stabilize the composite anode of lithium metal battery. [ABSTRACT FROM AUTHOR]