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Rechargeable aqueous zinc-ion batteries (AZIBs), a promising energy storage device in the large-scale energy storage market, have attracted extensive attention in recent years due to their high safety, low cost, environmental friendliness, and excellent electrochemical performance. Despite the rapid development of AZIBs technology, challenges such as insufficient energy density and limited cycling life still exist, which hinders the practical application of AZIBs. Due to the critical role that cathode materials play in the electrochemical performance of AZIBs, it is necessary to summarize the progress of cathode materials for AZIBs. In this review, the Zn2+ storage mechanisms of the cathode materials are analyzed. Subsequently, the representative cathode materials are introduced, and their structures and electrochemical performances are compared. The existing problems and improvement strategies of these cathode materials are summarized in detail. Finally, the future challenges and promising prospects for cathode materials are proposed. This review will guide researchers and manufacturers, benefiting them in designing advanced AZIBs for grid-scale energy storage.

Regulating the electronic structure of Bi-based materials by alloying engineering is promising to promote the electrocatalytic activity, but it remains some challenges to be solved. In this study, a facile electrochemical co-deposition strategy is developed to synthesize the bimetallic Bi9Cu1 alloy nanosheet on carbon cloth (Bi9Cu1/CC), which represents a novel self-supporting electrode for the electrocatalytic carbon dioxide (CO2) reduction reaction (CO2RR). The Bi9Cu1/CC catalyst has achieved a remarkable catalytic performance with high Faradaic efficiencies (FE) of over 90% for formate at wide potentials from −0.7 to −1.2 V vs. reversible hydrogen electrode (RHE). Moreover, the reversible Zn-CO2 battery can be driven by Bi9Cu1/CC cathode with a largest power density of 1.4 mW·cm−2, and superior operating stability. The systematic characterizations and electrochemical results confirm that the improved catalytic active sites, the enhanced mass/charge transport and the optimal reaction kinetics of Bi nanosheet are realized for CO2RR by Cu alloying. In situ attenuated total reflection infrared (ATR-IR) result confirms the bimetallic Bi-Cu active sites prefer to follow the ⋆OCHO conversion pathway. The density functional theory (DFT) calculations suggest that the Cu alloying contributes to the increased density of states near the Fermi surface of Bi and the optimized adsorption of ⋆OCHO intermediates on the Bi sites, resulting in the excellent catalytic performance. [ABSTRACT FROM AUTHOR]

Batteries dissolving active materials in liquids possess safety and size advantages compared to solid‐based batteries, yet the intrinsic liquid properties lead to material cross‐over induced self‐discharge both during cycling and idle when the electrolytes are in contact, thus highly efficient and cost‐effective solutions to minimize cross‐over are in high demand. An ultra‐low self‐discharge aqueous|organic membraneless battery using dichloromethane (CH2Cl2) and tetrabutylammonium bromide (TBABr) added to a zinc bromide (ZnBr2) solution as the electrolyte is demonstrated. The polybromide is confined in the organic phase, and bromine (Br2) diffusion‐induced self‐discharge is minimized. At 90% state of charge (SOC), the membraneless ZnBr2|TBABr (Z|T) battery shows an open circuit voltage (OCV) drop of only 42 mV after 120 days, 152 times longer than the ZnBr2 battery, and superior to 102 previous reports from all types of liquid active material batteries. The 120‐day capacity retention of 95.5% is higher than commercial zinc‐nickel (Zn–Ni) batteries and vanadium redox flow batteries (VRFB, electrolytes stored separately) and close to lithium‐ion (Li‐ion) batteries. Z|T achieves >500 cycles (2670 h, 0.5 m electrolyte, 250 folds of membraneless ZnBr2 battery) with ≈100% Coulombic efficiency (CE). The simple and cost‐effective design of Z|T provides a conceptual inspiration to regulate material cross‐over in liquid‐based batteries to realize extended operation. [ABSTRACT FROM AUTHOR]

Since the initial discovery of Ti3C2 a decade ago, there has been a significant surge of interest in 2D MXenes and MXene‐based composites. This can be attributed to the remarkable intrinsic properties exhibited by MXenes, including metallic conductivity, abundant functional groups, unique layered microstructure, and the ability to control interlayer spacing. These properties contribute to the exceptional electrical and mechanical performance of MXenes, rendering them highly suitable for implementation as candidate materials in flexible and wearable energy storage devices. Recently, a substantial number of novel research has been dedicated to exploring MXene‐based flexible materials with diverse functionalities and specifically designed structures, aiming to enhance the efficiency of energy storage systems. In this review, a comprehensive overview of the synthesis and fabrication strategies employed in the development of these diverse MXene‐based materials is provided. Furthermore, an in‐depth analysis of the energy storage applications exhibited by these innovative flexible materials, encompassing supercapacitors, Li‐ion batteries, Li–S batteries, and other potential avenues, is conducted. In addition to presenting the current state of the field, the challenges encountered in the implementation of MXene‐based flexible materials are also highlighted and insights are provided into future research directions and prospects. [ABSTRACT FROM AUTHOR]

Versatile cotton fabrics can be used in a variety of special environments and offer unparalleled advantages in textile products. In this work, bio-based phytic acid (PA), octadecylamine (ODA) and TiO2 (NPs) were used as raw materials to prepare multifunctional cotton fabrics with excellent flame retardant (LOI = 48.5%), hydrophobic (WCA = 152°), UV-blocking (UPF = 2000) and antibacterial (BR = 100%) properties through a facile and scalable dip coating and spraying process. Firstly, the phytic acid was grafted onto the surface of cotton fabric by esterification reaction between its phosphoric acid group and the hydroxyl group of cellulose molecules. Then ODA reacted with the residual phosphoric acid group of phytic acid to form an ODA layer, for further immobilizing TiO2 (NPs) particles on the surface of cotton fabric. The resulting cotton fabric possessed excellent flame resistance (LOI > 36.2%), hydrophobicity (WCA > 138°), UV-blocking (UPF = 2000) and antibacterial abilities (BR > 96.0%) even after 20 washing cycles. Moreover, this modification process did not sacrifice the desired cotton properties, including water vapor permeability, flexibility and tensile strength. This work proposed a simple and scalable pad-dry curing method to construct stable and multifunctional cotton textiles, which have broadened application prospects in many fields. [ABSTRACT FROM AUTHOR]

Styrene has been widely used as a reactive diluent for a variety of commercial unsaturated polyester resins (UPRs), but suffered from high volatility. In this work, we developed a bio‐based reactive diluent, 4‐vinylguaiacol glycidyl ether (DE4VG), via an epoxidation of 4‐vinylguaiacol (4VG). Excellent miscibility and high reactivity of DE4VG were demonstrated by a series of copolymerization tests with an unsaturated polyester prepolymer (named PMSD) synthesized from maleic anhydride, 1,3‐dihydroxypropane and succinic acid. While, significant advantages in terms of viscosity and volatility were confirmed. Additionally, DE4VG provides both vinyl and epoxide groups and the epoxide groups were cured using 4,4‐diamino diphenylmethane (DDM) to participate the network formation of the cured PMSD/DE4VG/TBPB/DDM resin, resulting in high glass transition temperature (Tg, 195°C), residual carbon (45.5%), tensile strength (41.75 MPa), and the elongation at break (4.5%), which were all significantly surpassed the cured PMSD/St/TBPB, PMSD/St/TBPB/DDM, PMSD/DE4VG/TBPB resin. This work provided a successful demonstration to replace styrene with a bio‐based reactive diluent in UPR preparation, not only overcame the high volatility of styrene, but also enhanced material performances of the cured resin. [ABSTRACT FROM AUTHOR]

Integration of hydrophobic and antibacterial functionalities into polyester‐cotton blended (PTCO) textiles has attracted more attention but remains a challenge. Here, a Janus fabric with antibacterial effect, hydrophobicity, and enhanced moisture‐permeability is fabricated using a “mist polymerization” approach. The PET fibers in the PTCO fabric are amino‐functionalized through ammonolysis reactions of PET molecules with HDA, and mist treatments of poly lauryl methacrylate (PLMA) and poly(DMC‐co‐MA) (PDM) are applied on the two side surfaces of the PTCO‐HDA fabric, respectively. The resulting Janus fabric exhibits an antibacterial rate of 99.9% against both E. coli and S. aureus, along with a hydrophobic property on its single side (PTCO‐HDA@PLMA). Additionally, the establishment of a surface‐free energy gradient across the fabric confers superior moisture‐permeability to the Janus fabric, offering advantages in preserving textile comfort. Moreover, this approach does not significantly compromise the original fabric properties, such as mechanical strength, moisture permeability, and fabric softness. The proposed method offers a straightforward and scalable strategy for textile finishing, demonstrating great potential in expanding the application scope of PTCO fabrics, and it may hold a pivotal role in diverse applications, notably encompassing home textiles, wound dressings, and high‐performance sportswear. [ABSTRACT FROM AUTHOR]

The article titled "An Ultra-Low Self-Discharge Aqueous|Organic Membraneless Battery with Minimized Br2 Cross-Over" discusses the design of a membraneless battery that has a low self-discharge rate. The researchers have developed a method to minimize the diffusion of polybromide species, which reduces self-discharge. This biphasic battery has the potential to provide large-scale energy storage with high safety and low cost. The article is authored by Xiang Liu, Yi Zhang, Yutong Wu, and their colleagues. [Extracted from the article]

With the rapid development of flexible displays and wearable electronics, there are a substantial demand for colorless transparent polyimide (CPI) films with different properties. Traditional trial‐and‐error experimental methods are time‐consuming and costly, and density functional theory based prediction of HOMO‐LUMO gap energy also takes time and is prone to varying degrees of error. Inspired by machine learning (ML) applications in molecular and materials science, this paper proposed a data‐driven ML strategy to study the correlation between microscopic molecular mechanisms and macroscopic optical properties. Based on varying degrees of impact of various molecular features on the cutoff wavelength (λcutoff), the ML algorithm is first used to quickly and accurately predict the λcutoff of CPI. Several new CPI films are then designed and prepared based on the key molecular features, and the predicted values of their λcutoff are effectively verified within the experimental error range. The interpretability provided by the model allows to establish correlations between the nine key descriptors identified and their physicochemical meanings. The contributions are also analyzed to the transparency of polyimide films, thereby giving insight into the molecular mechanisms underlying transparency modulation for CPIs. [ABSTRACT FROM AUTHOR]

Circularly polarized luminescence (CPL) materials are highly demanded due to their great potential in optoelectronic and chiroptical elements. However, the preparation of CPL films with high luminescence dissymmetry factors (glum) remains a formidable task, which impedes their practical application in film‐based devices. Herein, a facile strategy to prepare solid CPL film with a high glum through exogenous chiral induction and amplification of liquid crystal polymers is proposed. Amplification and reversion of the CPL appear when the films are annealed at the chiral nematic liquid crystalline temperature and the maximal glum up to 0.30 due to the enhancement of selective reflection. Thermal annealing treatment at different liquid crystalline states facilitates the formation of the chiral liquid phase and adjusts the circularly polarized emission. This work not only provides a straightforward and versatile platform to construct organic films capable of exhibiting strong circularly polarized emission but also is helpful in understanding the exact mechanism for the liquid crystal enhancement of CPL performance. [ABSTRACT FROM AUTHOR]

Batteries dissolving active materials in liquids possess safety and size advantages compared to solid-based batteries, yet the intrinsic liquid properties lead to material cross-over induced self-discharge both during cycling and idle when the electrolytes are in contact, thus highly efficient and cost-effective solutions to minimize cross-over are in high demand. An ultra-low self-discharge aqueous|organic membraneless battery using dichloromethane (CH 2 Cl 2 ) and tetrabutylammonium bromide (TBABr) added to a zinc bromide (ZnBr 2 ) solution as the electrolyte is demonstrated. The polybromide is confined in the organic phase, and bromine (Br 2 ) diffusion-induced self-discharge is minimized. At 90% state of charge (SOC), the membraneless ZnBr 2 |TBABr (Z|T) battery shows an open circuit voltage (OCV) drop of only 42 mV after 120 days, 152 times longer than the ZnBr 2  battery, and superior to 102 previous reports from all types of liquid active material batteries. The 120-day capacity retention of 95.5% is higher than commercial zinc-nickel (Zn-Ni) batteries and vanadium redox flow batteries (VRFB, electrolytes stored separately) and close to lithium-ion (Li-ion) batteries. Z|T achieves >500 cycles (2670 h, 0.5 m electrolyte, 250 folds of membraneless ZnBr 2  battery) with ≈100% Coulombic efficiency (CE). The simple and cost-effective design of Z|T provides a conceptual inspiration to regulate material cross-over in liquid-based batteries to realize extended operation., (© 2024 The Authors. Advanced Science published by Wiley-VCH GmbH.)