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Eutectic electrolytes show potential beyond conventional low‐concentration electrolytes (LCEs) in zinc (Zn)‐ion capacitors (ZICs) yet suffer from high viscosity and sluggish kinetics. Herein, we originally propose a universal theory of intrinsically decoupling to address these issues, producing a novel electrolyte termed "quasi‐eutectic" electrolyte (quasi‐EE). Joint experimental and theoretical analyses confirm its unique solution coordination structure doped with near‐LCE domains. This enables the quasi‐EE well inherit the advanced properties at deep‐eutectic states while provide facilitated kinetics as well as lower energy barriers via a vehicle/hopping‐hybridized charge transfer mechanism. Consequently, a homogeneous electroplating pattern with much enhanced Sand's time is achieved on the Zn surface, followed by a twofold prolonged service‐life with drastically reduced concentration polarization. More encouragingly, the quasi‐EE also delivers increased capacitance output in ZICs, which is elevated by 12.4 %–144.6 % compared to that before decoupling. Furthermore, the pouch cell with a cathodic mass loading of 36.6 mg cm−2 maintains competitive cycling performances over 600 cycles, far exceeding other Zn‐based counterparts. This work offers fresh insights into eutectic decoupling and beyond. [ABSTRACT FROM AUTHOR]

Unstable Zn interface with serious detrimental parasitic side‐reactions and uncontrollable Zn dendrites severely plagues the practical application of aqueous zinc‐ion batteries. The interface stability was closely related to the electrolyte configuration and Zn2+ depositional behavior. In this work, a unique Zn‐ion anchoring strategy is originally proposed to manipulate the coordination structure of solvated Zn‐ions and guide the Zn‐ion depositional behavior. Specifically, the amphoteric charged ion additives (denoted as DM), which act as zinc‐ion anchors, can tightly absorb on the Zn surface to guide the uniform zinc‐ion distribution by using its positively charged −NR4+ groups. While the negatively charged −SO3− groups of DM on the other hand, reduces the active water molecules within solvation sheaths of Zn‐ions. Benefiting from the special synergistic effect, Zn metal exhibits highly ordered and compact (002) Zn deposition and negligible side‐reactions. As a result, the advanced Zn||Zn symmetric cell delivers extraordinarily 7000 hours long lifespan (0.25 mA cm−2, 0.25 mAh cm−2). Additionally, based on this strategy, the NH4V4O10||Zn pouch‐cell with low negative/positive capacity ratio (N/P ratio=2.98) maintains 80.4 % capacity retention for 180 cycles. A more practical 4 cm*4 cm sized pouch‐cell could be steadily cycled in a high output capacity of 37.0 mAh over 50 cycles. [ABSTRACT FROM AUTHOR]

Dendritic growth and severe side reactions remain challenging problems for advancing aqueous zinc‐ion batteries. Those critical issues are closely related to the interfacial chemistry, solvation structure, and transportation kinetics of zinc ions. Herein, a regulated ion‐conductive electrode–electrolyte interface (PVA‐Zn(CF3SO3)2‐Si3N4, denoted as PZS) on Zn metal has been in situ constructed, which simultaneously solves the above‐mentioned issues. PZS can effectively accelerate ion transportation and extrude interfacial water, thus endowing dendrite‐free Zn deposition and eliminating side reactions. Benefiting from these features, the PZS‐Zn exhibits stable and reversible Zn stripping/plating with an ultralong cycling life of 3800 h, and an ultrahigh Coulombi efficiency of 99.8%. The full cell paired with the NH4V4O10 cathode runs stably over 1000 cycles at 5 A g−1 with near 100% capacity retention and is demonstrated to cycle up to 200 times along with 71.94% capacity retention in a practical cathode‐anode coupling configuration pouch cell. With this interfacial design, the assembled zinc batteries display excellent cycling stability, paving a practical way for aqueous Zn‐storage systems. [ABSTRACT FROM AUTHOR]

Sodium sulfide has been widely used as a bismuth depressant in the flotation separation of molybdenum–bismuth sulfide ores. However, the selective depression mechanism of sodium sulfide on bismuthinite remained unclear. In this study, the effect of sodium sulfide on the flotation performance of molybdenite and bismuthinite was systemically investigated through micro-flotation tests, bench-scale flotation tests, Fourier transform infrared (FTIR) measurements, adsorption experiments, and X-ray photoelectron spectroscopy (XPS) analyses. Micro-flotation tests indicated that sodium sulfide had excellent depressing effect on the bismuthinite in alkaline condition. The recovery of bismuthinite dramatically decreased from 86.7% to 16.5% with the concentration of sodium sulfide increased to 1 × 10−3 mol/L. By contrast, the depressing effect of sodium sulfide on the flotation of molybdenite was weak. The flotation recovery of molybdenite remained above 60% in the whole pH range tested. Surface analysis using FTIR and XPS analysis revealed that the surface of bismuthinite was covered by hydrophilic sulfide ions after treatment with sodium sulfide, which not only decreased its surface hydrophobicity but also prevented the subsequent adsorption of collector xanthate. While the surface of molybdenite was slightly affected and remained hydrophobic as indicated by high flotation recoveries. Bench-scale flotation tests confirmed that sodium sulfide could be used as an efficient depressant for flotation separation of molybdenite from bismuthinite. The work presented here not only provides a new perspective on the inhibition mechanism of sodium sulfide but also gives a theoretical support for the industrial application of sodium sulfide. [ABSTRACT FROM AUTHOR]

Unstable Zn interface with serious detrimental parasitic side-reactions and uncontrollable Zn dendrites severely plagues the practical application of aqueous zinc-ion batteries. The interface stability was closely related to the electrolyte configuration and Zn 2+ depositional behavior. In this work, a unique Zn-ion anchoring strategy is originally proposed to manipulate the coordination structure of solvated Zn-ions and guide the Zn-ion depositional behavior. Specifically, the amphoteric charged ion additives (denoted as DM), which act as zinc-ion anchors, can tightly absorb on the Zn surface to guide the uniform zinc-ion distribution by using its positively charged -NR 4 + groups. While the negatively charged -SO 3 - groups of DM on the other hand, reduces the active water molecules within solvation sheaths of Zn-ions. Benefiting from the special synergistic effect, Zn metal exhibits highly ordered and compact (002) Zn deposition and negligible side-reactions. As a result, the advanced Zn||Zn symmetric cell delivers extraordinarily 7000 hours long lifespan (0.25 mA cm -2 , 0.25 mAh cm -2 ). Additionally, based on this strategy, the NH 4 V 4 O 10 ||Zn pouch-cell with low negative/positive capacity ratio (N/P ratio=2.98) maintains 80.4 % capacity retention for 180 cycles. A more practical 4 cm*4 cm sized pouch-cell could be steadily cycled in a high output capacity of 37.0 mAh over 50 cycles., (© 2024 Wiley-VCH GmbH.)