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The most commonly used zinc foil anode for aqueous zinc‐ion batteries suffers from poor cycle stability and low zinc utilization. Zinc‐plated anodes on the host materials with high zincophilicity and stability are receiving increasing attention to alleviate these above issues. Here, the high zinc deposition activity of Cu (2 2 0) is confirmed through experimental observations and theoretical calculations and then Cu (2 2 0) substrates are prepared with the highly preferred orientation through an industrial electrolysis strategy. The prepared Cu (2 2 0) substrate can consistently modulate dense zinc growth by inducing the Zn (0 0 1) growth with the lowest surface energy and exposing high‐index zinc facets due to its exceptional grain size, high deposition activity, and homogeneous crystal orientation, which result in the high zinc plating/stripping reversibility of this Cu (2 2 0) substrate. When assembled into the Zn//MnO2 battery, the zinc‐plated Cu (2 2 0) can deliver capacity retention of 93.9% after 640 cycles at high zinc utilization (≈20%). This scalable orientation design strategy provides a new perspective for realizing dendrite‐free metal deposition with special textures. [ABSTRACT FROM AUTHOR]

The booming of aqueous zinc‐ion batteries (AZIBs) draws the researchers' attention to issues of zinc metal anodes, such as uncontrollable dendrite growth, corrosion, and volume effects. Zinc powder anode is more suitable for the industrial application of AZIBs than the widely used zinc foil anode due to its low cost, tunability and processability. However, the related solutions are rarely studied because the above issues of zinc metal anode are more serious in zinc powder anode. Herein, for the first time, we design a semi‐solid zinc slurry anode consisting of zinc powder and zincophilic tin additive dispersed in a conductive elastic rheological network. Zinc can be deposited homogeneously on the dispersed tin particles, which avoids agglomerative zinc deposition and alleviates volume change during repeated zinc stripping/plating. Moreover, the practical application of the full cell with slurry is very promising since its operating life can be easily extended by facile slurry renewal. [ABSTRACT FROM AUTHOR]

For various applications of negative temperature coefficient (NTC) thermistors, it is useful to develop a material system to achieve different room-temperature resistivities (ρ25) and temperature sensitivity (B value) by adjusting slightly the chemical composition. Here, B3+/Na+-modified NiO-based ceramics (denoted as xB/yNa-NiO, 0 ≤ x ≤ 0.04 and 0 ≤ y ≤ 0.07) were prepared for NTC thermistors. The phase component and microstructure of the ceramics were detected respectively by using X-ray diffraction and scanning electron microscope. The related electrical properties and temperature sensitivity were investigated by analyzing the resistivity-temperature characteristic and related complex impedance spectra. The results show that all the prepared ceramics have a cubic crystalline structure and present typical NTC characteristics. By changing the concentrations of B3+- and Na+-ions in the compounds, ρ25 from 47.94 Ω cm to 1.024 MΩ cm and B values from 2582 to 8019 K were achieved. The analysis of complex impedance spectra reveals that both grain effect and grain boundary effect contribute to the electrical conduction and NTC feature. The conduction mechanisms combining with band conduction and polaron hopping model are proposed for the NTC effect in xB/yNa-NiO thermistors. [ABSTRACT FROM AUTHOR]

Copper ferrite ceramics, CuFe2−xVxO4 (x = 0, 0.015, 0.03, 0.04 and 0.05), were prepared by a wet-chemical synthesis method followed by the traditional ceramic sintering process. The influence of V-ion content on phase component, ionic valence states, microstructures and electrical properties of the ceramics was investigated. The X-ray diffraction analysis shows that all the ceramics have cubic structure of spinel CuFe2O4 phase. All ceramics show the typical characteristic of negative temperature coefficient (NTC) of resistivity in the measurement temperature region between 25 and 250 °C. The temperature-sensitivity parameters of the ceramics can be adjusted from 3319 to 4920 K by changing the content of V-ions. The analysis of complex impedance revealed that both grain effect and grain-boundary effect contributed to the electrical properties of the ceramics. The possible conduction mechanism was proposed to be a thermal-activated polaron hopping conduction. [ABSTRACT FROM AUTHOR]

Three dimensional (3D) framework structure is one of the most effective ways to achieve uniform zinc deposition and thus inhibit the Zn dendrites growth in working Zn metallic anode. A major challenge facing for the most commonly used 3D zincophilic hosts is that the zincophilic layer tends to peel off during repeatedly cycling, making it less stable. Herein, for the first time, a hetero-superlattice Zn/ZnLi (HS-Zn/ZnLi) anode containing periodic arrangements of metallic Zn phase and zincophilic ZnLi phase at the nanoscale, is well designed and fabricated via electrochemical lithiation method. Based on binding energy and stripping energy calculation, and the operando optical observation of plating/stripping behaviors, the zincophilic ZnLi sites with a strong Zn adsorption ability in the interior of the 3D ZnLi framework structure can effectively guide uniform Zn nucleation and dendrite-free zinc deposition, which significantly improves the cycling stability of the HS-Zn/ZnLi alloy (over 2800 h without a short-circuit at 2 mA cm -2 ). More importantly, this strategy can be extended to HS-Zn/ZnNa and HS-Zn/ZnK anodes that are similar to the HS-Zn/ZnLi microstructure, also displaying significantly enhanced cycling performances in AZIBs. This study can provide a novel strategy to develop the dendrite-free metal anodes with stable cycling performance., (© 2024 Wiley-VCH GmbH.)

Aqueous zinc-ion battery is regarded as one of the promising devices for large-scale energy storage systems owing to its high safety, cost-effectiveness, and competitive electrochemical properties. However, the dendrite growth on zinc metal anodes dramatically hinders its further practical applications, and the internal mechanism of dendrite evolution is still unclear. The introduction of a protective layer on the anode interface is an effective method to avoid zinc dendrite growth. Herein, a two-dimensional (2D) atomic surface diffusion mechanism is proposed to reveal the evolution of zinc deposition from tiny protrusion to dendrite under uneven electric and ionic fields. Further, the conductive copper nitride (CN) protective layer is constructed on the zinc metal anode by a facile and scalable magnetron sputtering approach. Their protective layer possesses a high zinc affinity and high diffusion barrier for zinc atom migration, leading to spacious nucleation, and uniform zinc deposition, thus significantly boosting the electrochemical stability. For the first time, the role of the restricted 2D atomic surface diffusion mechanism in inhibiting the formation of zinc tiny protrusion that induces uneven electric and ionic fields is revealed. This work can provide a novel insight for future research on dendrite-free zinc metal anodes by interfacial modification., (© 2021 Wiley-VCH GmbH.)

Objective To construct the recombinant eukaryotic expression vector of human mitochondrial transcription termination factor 2 (MTERF2) gene and determine the cellular localization by overexpressing MTERF2 in human Caski cervical cancer cells. Methods The coding sequence of MTERF2 was amplified by reverse transcription-PCR using the total RNA extracted from human cervical cancer Caski cells, and then was inserted into p3×FLAG-CMV-14 vector. After being verified by PCR and DNA sequencing, the positive recombinant plasmid was transiently transfected into Caski cells. Western blotting and immunofluorescence technique were performed to analyze the expression and distribution of human MTERF2 proteinat 24, 32 and 48 hours after transfection. Results Sequence analysis showed that the correct target gene (1158 bp) was inserted into the vector at the expected position. The target protein band was detected at M r 44 000 as we had predicted in the transfected cells while not in the negative control group, which indicated MTERF2 expression vector could be successfully transfected and expressed in Caski cells. The p3×FLAG-MTERF2 protein was highly expressed and displayed a mitochondrial distribution at 24 hours post-transfection in Caski cells. Conclusion We successfully constructed the eukaryotic expression plasmid p3×FLAG-CMV-MTERF2 and expressed p3×FLAG tagged MTERF2 effectively in the mitochondria of Caski cells.