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The practical use of Zn metal anodes in aqueous zinc batteries is impeded by the growth of dendrites, anode corrosion, and hydrogen evolution reaction in aqueous electrolytes. In this study, a simple, energy‐efficient, and scalable approach is reported to mitigate these detrimental issues effectively. Using 1‐hexanethiol (HT), a hydrophobic self‐assembled mercaptan layer (SAML) with a highly ordered structure is in situ created on the surface of the Zn anode. This ultrathin interfacial structure guides uniform Zn deposition and shields the Zn anode from water and oxygen‐induced corrosion, thus effectively inhibiting dendrite formation and side reactions. Consequently, the HT‐Zn electrode showcases impressive electrochemical stability and reversibility, and the as‐assembled HT‐Zn||I2 full cell delivers increased specific capacity (from 112 to 155 mAh g−1 at 1 A g−1) and ultra‐stable cyclability (zero capacity decay during the extended 1500 cycles at 4 A g−1). To validate the effectiveness of this simple and scalable method, a large‐sized pouch cell is prepared, which can be stably operated for 1000 cycles with a capacity decay of merely 0.0098% per cycle and Coulombic efficiency exceeding 99.1%. The presented SAML strategy highlights the potential of molecular engineering in improving the performance of aqueous zinc batteries. [ABSTRACT FROM AUTHOR]

Aqueous zinc metal batteries are a viable candidate for cost-effective energy storage. However, the cycle life of the cell is adversely affected by the morphological evolution of the metal electrode surface upon prolonged cycling. Here, we investigate different electrochemical protocols to favour the formation of stable zinc metal electrode surface morphologies. By coupling electrochemical and optical microscopy measurements, we demonstrate that an initial zinc deposition on the metal electrode allows homogeneous stripping and plating processes during prolonged cycling in symmetric Zn||Zn cell. Interestingly, when an initially plated zinc metal electrode is tested in combination with a manganese dioxide-based positive electrode and a two molar zinc sulfate aqueous electrolyte solution in coin cell configuration, a specific discharge capacity of about 90 mAh g−1 can be delivered after 2000 cycles at around 5.6 mA cm−2 and 25 °C. Long-lasting zinc metal electrodes are crucial in developing commercial zinc-based batteries. Here, the authors investigate the different morphology evolution between the stripping and plating process and propose electrochemical protocols to prolong the lifespan of zinc anodes. [ABSTRACT FROM AUTHOR]

Selectivity and uniformity are the stuck issues for the NbOx–based selectors applied in memory arrays. In this letter, we experimentally demonstrated that the selector through Al-doping had significant improvement of selectivity (250%) and uniformity (from 4% to 1%). To understand the physical mechanism, the thermoelectric coupling model was employed. It was simulatively illustrated that lower OFF current and higher selectivity were induced by the increase of the Schottky barrier height and Schottky distance. Meanwhile, the ability of constraining oxygen vacancies reduced the random immigration, which contributed to a better uniformity. This study provided an effective way to improve the performance of the selectors and overcome the barrier in the application of 3D integrated memory. [ABSTRACT FROM AUTHOR]

In this article, we demonstrate a high-performance Pt/NbOx/Ru selector based on metal–insulator transition (MIT), which exhibits low leakage current (5.67 × 10 −5 A/cm2), excellent endurance (>106), and ultrahigh uniformity (<2.5%) in particular and performs great potential to achieve 3-D storage integration. Furthermore, the decrease of the threshold voltage drift and the improvement of stability can be interpreted as the formation of RuO2 layer at the interface between Ru electrode and oxide layer. The application of Ru in selector provides the industry with a choice to enhance the uniformity and stability. [ABSTRACT FROM AUTHOR]

The niobium oxide insulator–metal transition selector device is considered to be a rectifying device with great potential. However, the lack of research on the experimental parameters and the complex physical mechanism of the NbO2 device seriously affected its development. In this article, a controllable intermediate functional layer of NbOx was reported in the Pt/NbOx/TiN device subjected to different forming compliance currents (FCCs) and compliance currents (CCs). The different FCCs and CCs changed the size of the Nb2O5 and NbO2 layers within the NbOx layer, which further affected the threshold voltage. The result helped to realize the control of the NbOx functional layer, which was also of great significance for the adjustment of the experimental parameters in the preparation experiment according to the required performance. Furthermore, the I-V characteristics and switching times at different ambient temperatures were carried out, showing the specific dependency of the device on temperature. Between them, the simulated switching time of 2 ns at room temperature proved that the selector had a great application prospect in high speed and high-density storage or logic switch. Generally, the whole research helped to improve the control of the interlayer structure and the performance of the device for application in 3-D crossbar arrays, and provided a valid model to study the device. [ABSTRACT FROM AUTHOR]

In the study of resistive random access memory using GeTeOx film as the switching layer, the device performed excellent property of bipolar resistive switching (BRS), which could be gradually transformed to the complementary resistive switching (CRS) by varying SET process current compliance. The conductive filament conduction mechanism of BRS could be verified by electrical characteristics and reliable data fitting. Through increasing current compliance of the SET process, CRS could be achieved due to higher activity of oxygen vacancies originated from the intensified thermal effect. This paper was beneficial to understand the switching mechanisms of BRS and CRS and provide a method to realize interconversion. Moreover, it was also a potential and promising device to be applied in the neurosynaptic biomimetic field. [ABSTRACT FROM AUTHOR]