Electron Bridge Effect Induced by Iodide Catalysis for Enhancing ZnS Activation in Aqueous Zinc–Sulfur Batteries

Aqueous zinc-sulfur (Zn-S) batteries show great potential for unlocking high energy and safety aqueous batteries. Yet, the sluggish kinetic and poor redox reversibility of the sulfur conversion reaction in aqueous solution challenge the development of Zn-S batteries. Here, we fabricate a high-performance Zn-S battery using highly water-soluble ZnI2 as an effective catalyst. In situ experimental characterizations and theoretical calculations reveal that the strong interaction between I- and the ZnS nanoparticles (discharge product) leads to the atomic rearrangement of ZnS, weakening the Zn-S bonding, and thus facilitating the electrochemical oxidation reaction of ZnS to S. The aqueous Zn-S battery exhibited a high energy density of 742 Wh kg(sulfur) -1 at the power density of 210.8 W kg(sulfur) -1 and good cycling stability over 550 cycles. Our findings provide new insights about the iodide catalytic effect for cathode conversion reaction in Zn-S batteries, which is conducive to promoting the future development of high-performance aqueous batteries.

Aqueous zinc‐sulfur (Zn‐S) batteries show great potential for unlocking high energy and safety aqueous batteries. Yet, the sluggish kinetic and poor redox reversibility of the sulfur conversion reaction in aqueous solution challenge the development of Zn‐S batteries. Here, we fabricate a high‐performance Zn‐S battery using highly water‐soluble ZnI2 as an effective catalyst. In situ experimental characterizations and theoretical calculations reveal that the strong interaction between I− and the ZnS nanoparticles (discharge product) leads to the atomic rearrangement of ZnS, weakening the Zn‐S bonding, and thus facilitating the electrochemical oxidation reaction of ZnS to S. The aqueous Zn‐S battery exhibited a high energy density of 742 Wh kg(sulfur)−1 at the power density of 210.8 W kg(sulfur)−1 and good cycling stability over 550 cycles. Our findings provide new insights about the iodide catalytic effect for cathode conversion reaction in Zn‐S batteries, which is conducive to promoting the future development of high‐performance aqueous batteries.

Construction of coordination bond electron bridge boosting interfacial electron transfer to enhance bifunctional photocatalytic activity of TiO2/g-C3N4 heterojunction

The effects of different donors, acceptors and electron bridges on various properties of novel organic electro-optic materials were investigated.

Recent advancement in electrolyte optimization for rechargeable aqueous zinc–sulfur (Zn–S) batteries

Aqueous zinc–sulfur (Zn–S) batteries garner significant attention for energy torage due to high capacity, cost‐efficiency, and eco‐sustainability. However, the sluggish solid–solid conversion and poor cycling impede their further development. Herein, a dual‐functional choline iodide (CHI) redox mediator is introduced to manipulate the sulfur electrochemistry and Zn anode. For the cathode, the addition of CHI cannot only facilitate the oxidation process of ZnS by enlarging the bonding length on the ZnS surface but also form a protective layer that inhibits the side reactions involving H2S, SO42− and the decomposition of water, thereby improving its redox reversibility. Regarding the Zn anode, CHI effectively reduces nucleation overpotential, mitigates the distortion of electric and potential fields, and promotes uniform Zn deposition through electrostatic shielding. Consequently, the assembled Zn–S battery delivers a high specific capacity of 1666 mAh g−1 at 1 A g−1, an impressive rate performance of 1071 mAh g−1 at 4 A g−1, while the nucleation overpotential is significantly reduced from 31.9 to 11.5 mV. This work exemplifies an effective strategy to boost high‐performance Zn–S battery capacity, paving the way for the rational design redox mediators in sulfur electrochemistry.

Carbon bridge effects regulate TiO2–acrylate fluoroboron coatings for efficient marine antifouling

Rechargeable aqueous zinc ion batteries are enabled by the (de)intercalation chemistry, but bottlenecked by the limited energy density due to the low capacity of cathodes. In this work, carbon nanotubes supported 50 wt% sulfur (denoted as S@CNTs‐50), as a conversional cathode, is employed and a high energy density aqueous zinc–sulfur (Zn–S) battery is constructed . In the electrolyte of 1 m Zn(CH3COO)2 (pH = 6.5) with 0.05 wt% I2 additive where I2 can serve as medium of Zn2+ ions to reduce the voltage hysteresis of S@CNTs‐50 and stabilize Zn stripping/plating, S@CNTs‐50 delivers a high capacity of 1105 mAh g−1 with a flat discharge voltage of 0.5 V, realizing an energy density of 502 Wh kg−1 based on sulfur, which is one of the highest values reported in aqueous Zn‐based batteries that use mild electrolyte. Moreover, the chemical materials cost of this aqueous Zn–S battery can be lowered to be $45 kWh−1 due to the cheap raw materials, reaching to the level of pumped energy storage. Ex situ X‐ray diffraction, Raman spectra, X‐ray photoelectron spectrum, and transmission electron microscopy measurements reveal that sulfur cathode undergoes a conversion reaction between S and ZnS.

Recently, aqueous zinc-ion batteries with conversion mechanisms have received wide attention in energy storage systems on account of excellent specific capacity, high power density, and energy density. Unfortunately, some characteristics of cathode material, zinc anode, and electrolyte still limit the development of aqueous zinc-ion batteries possessing conversion mechanism. Consequently, this paper provides a detailed summary of the development for numerous aqueous zinc-based batteries: zinc-sulfur (Zn-S) batteries, zinc-selenium (Zn-Se) batteries, zinc-tellurium (Zn-Te) batteries, zinc-iodine (Zn-I2) batteries, and zinc-bromine (Zn-Br2) batteries. Meanwhile, the reaction conversion mechanism of zinc-based batteries with conversion mechanism and the research progress in the investigation of composite cathode, zinc anode materials, and selection of electrolytes are systematically introduced. Finally, this review comprehensively describes the prospects and outlook of aqueous zinc-ion batteries with conversion mechanism, aiming to promote the rapid development of aqueous zinc-based batteries.

Dual electron reservoirs: Synergistic photocatalytic degradation of antibiotics by oxygen vacancy-rich BiOBr nanoflowers and magnetic carbon nanotubes

Substituting natural seawater (NS) for deionized water significantly reduces the electrolyte manufacturing cost of aqueous zinc (Zn) ion batteries, but it also poses severe corrosion challenges to the Zn metal anode, given the presence of the Cl − /H 2 O‐rich Zn‐electrolyte interface. Here, a NS electrolyte featuring NS solvent and the host–guest complex additive is designed. The 2‐mercaptobenzothiazole (MBT) guest shows sustained‐release behavior from the cyclodextrin host dominated by its aqueous solubility in the NS electrolyte. Crucially, Cl − ions facilitate a compact MBT shield at the interface via bridging effects, creating a Cl − /H 2 O‐poor microenvironment that suppresses corrosion and extends Zn anode cycle life. Thus, the Zn anode achieves an extended cycling life of 400 h in the Zn||Zn symmetric cell even under a practical depth of discharge of 42.7%. The Zn||NaV 3 O 8 ·1.5H 2 O full cell with a low negative/positive capacity ratio of 1.92 exhibits 99% capacity retention at 0.5 A g −1 after 600 cycles, and the Ah‐level pouch cell with an initial discharge capacity of 1.21 Ah maintains stable cycling for 50 cycles.

Substituting natural seawater (NS) for deionized water significantly reduces the electrolyte manufacturing cost of aqueous zinc (Zn) ion batteries, but it also poses severe corrosion challenges to the Zn metal anode, given the presence of the Cl-/H2O-rich Zn-electrolyte interface. Here, a NS electrolyte featuring NS solvent and the host-guest complex additive is designed. The 2-mercaptobenzothiazole (MBT) guest shows sustained-release behavior from the cyclodextrin host dominated by its aqueous solubility in the NS electrolyte. Crucially, Cl- ions facilitate a compact MBT shield at the interface via bridging effects, creating a Cl-/H2O-poor microenvironment that suppresses corrosion and extends Zn anode cycle life. Thus, the Zn anode achieves an extended cycling life of 400h in the Zn||Zn symmetric cell even under a practical depth of discharge of 42.7%. The Zn||NaV3O8·1.5H2O full cell with a low negative/positive capacity ratio of 1.92 exhibits 99% capacity retention at 0.5 A g-1 after 600 cycles, and the Ah-level pouch cell with an initial discharge capacity of 1.21 Ah maintains stable cycling for 50 cycles.

Using wide-band-gap BiOCl to greatly enhance the photocarriers separation of AgI via in-situ Ag bridge: Interfacial electron transfer route, density functional theory calculation and mechanism study

Minireview on Aqueous Zinc–Sulfur Batteries: Recent Advances and Future Perspectives

Improving the electrical conductivity of sulfur cathode while ensuring its high affinity to catalyst holds the key to facilitate the reaction kinetics of aqueous zinc–sulfur batteries. Herein, the sulfur redox in aqueous electrolyte is accelerated by introducing selenium–sulfur bonds into the sulfur structure to build an internal electron transport path. The Se with less electronegativity can act as an electron donor to accelerate the binding between S and Zn2+. Meanwhile, the bonded Se in the electron‐poor state endows the modified sulfur cathode with a strong affinity to the I3− catalyst, which further facilitates the conversion efficiency. Thus, the internal electron donor assisted sulfur cathode delivers excellent electrochemical performance in terms of high reversible capacity (1490 mAh g−1 at 0.5 A g−1), competitive rate performance (1010 mAh g−1 at 4 A g−1), as well as outstanding cycle stability (735 mAh g−1 at 4 A g−1 after 500 cycles).