Key Takeaways & Executive Findings
- •• A trace electrolyte additive (sulfobutyl-grafted β-cyclodextrin) self-assembles into an interconnecting molecular interface on zinc anodes, enhancing Zn2+ transference number and homogenizing deposition sites. • The interface accelerates desolvation of hydrated Zn2+ and suppresses parasitic reactions, achieving 99.7% Coulombic efficiency and ~30-fold increase in operation lifetime. • Zinc-ion hybrid supercapacitors with the modified anodes deliver 20,000-cycle stability and improved rate capability, bridging high energy and power densities. • This scalable interface engineering strategy offers a promising route to ultrastable, fast-kinetics zinc anodes for next-generation aqueous energy storage.
Abstract
Zinc-ion hybrid supercapacitors (ZHSs) are promising energy storage systems integrating high energy density and high-power density, whereas they are plagued by the poor electrochemical stability and inferior kinetics of zinc anodes. Herein, we report an electrolyte additive-assembled interconnecting molecules–zinc anode interface, realizing highly stable and fast-kinetics zinc anodes for ZHSs. The sulfobutyl groups-grafted β-cyclodextrin (SC) supramolecules as a trace additive in ZnSO4 electrolytes not only adsorb on zinc anodes but also self-assemble into an interconnecting molecule interface benefiting from the mutual attraction between the electron-rich sulfobutyl group and the electron-poor cavity of the adjacent SC supramolecule. The interconnecting molecules–zinc anode interface provides abundant anion-trapping cavities and zincophilic groups to enhance Zn2+ transference number and homogenize Zn2+ deposition sites, and meanwhile, it accelerates the desolvation of hydrated Zn2+ to improve zinc deposition kinetics and inhibit active water molecules from inducing parasitic reactions at the zinc deposition interface, making zinc anodes present superior reversibility with 99.7% Coulombic efficiency, ~30 times increase in operation lifetime and an outstanding cumulative capacity at large current densities. ZHSs with 20,000-cycle life and optimized rate capability are thereby achieved. This work provides an inspiring strategy for designing zinc anode interfaces to promote the development of ZHSs.
1. Introduction
The urgent problems of energy shortage and environmental pollution are driving new technologies in the field of energy storage. Aqueous zinc-ion hybrid supercapacitors (ZHSs) theoretically combine the advantages of batteries and supercapacitors, presenting the potential to realize extreme safety, high energy density, fast charge/discharge rate and ultralong lifespan [1, 2]. Therefore, zinc-based ZHSs have been regarded as a competitive candidate for next-generation energy storage systems. Although applying zinc metal anodes with a large theoretical capacity (820 mAh g−1 and 5855 Ah L−1) and low redox potential (-0.763 V vs. standard hydrogen electrode) is conducive to improving the energy density of ZHSs [3, 4], the electrochemical instability and sluggish kinetics make zinc anodes hard to match capacitive cathodes (e.g., porous carbon) with ultralong cycle life and fast charge storage/release ability in ZHSs.
To be specific, the thermodynamically favorable form of zinc ions in aqueous zinc-salt electrolytes is hydrated ions, such as [Zn(H2O)n]2+ (n = 5–6) in aqueous 2 M ZnSO4 solution which is a widely used electrolyte for ZHSs. The desolvation of hydrated zinc ions at the electrolyte–zinc anode interface has to overcome a high energy barrier, thus limiting the electrochemical kinetics of zinc anodes [5, 6], and meanwhile, the free water molecules desolvated from the solvation shell of the hydrated zinc ions not only corrode metallic zinc anodes to generate electrically insulated zinc hydroxides but also are easily reduced to hydrogen gas [7–9]. The hydrogen evolution and corrosion reactions disrupt both the electric field and ion field of the zinc deposition interface, causing inhomogeneous zinc deposition and finial zinc dendrites [10, 11]. In addition, zinc electrodeposition starts with the generation of scattered zinc nuclei at the zinc deposition interface, while the newly formed zinc nucleus with a large curvature radius and high surface energy creates the “tip effect” and spontaneously attracts zinc ions to laterally diffuse to deposit on them [12, 13], which is also an important factor inducing the formation of dendrites. As a result, the dendrite growth, parasitic reaction and high desolvation energy barrier issues result in inferior electrochemical stability and sluggish kinetics of zinc anodes, making it impossible to realize ultralong-life and high-rate ZHSs.
To solve the above-mentioned dendrite growth and parasitic reaction issues of zinc anodes, considerable efforts have been dedicated to manipulating electrolyte solvation structure and regulating zinc deposition interface chemistry.
Loading authentic research manuscript (Pages 1–5)...
Yang Li, Xu Li, Xinya Peng, Xinyu Yang, Feiyu Kang, Liubing Dong (2025). Electrolyte Additive-Assembled Interconnecting Molecules–Zinc Anode Interface for Zinc-Ion Hybrid Supercapacitors. Nano-Micro Letters. https://doi.org/10.1007/s40820-025-01794-1
Research & Educational Purpose Only:The translations, structured abstracts, analytical annotations, and data reports provided by SinoTechIntel are intended exclusively for academic research, internal corporate R&D, and educational benchmarking. They do not constitute formal engineering, chemical safety, legal, or professional advice.
Copyright & Intellectual Property Notice: Original copyright of the underlying source articles and experimental data remains with the respective authors, institutions, and original publishing journals. SinoTechIntel claims intellectual property only over its proprietary translations, analytical syntheses, and AEO structured enhancements in accordance with international fair use and academic citation principles.
Frequently Asked Questions
What is the main challenge addressed in this paper?
The paper addresses the poor electrochemical stability and sluggish kinetics of zinc anodes in zinc-ion hybrid supercapacitors, which limit their cycle life and rate capability.
How does the electrolyte additive improve zinc anode performance?
The sulfobutyl-grafted β-cyclodextrin additive self-assembles into an interconnecting molecular interface on the zinc anode, which enhances Zn2+ transference, homogenizes deposition, accelerates desolvation, and suppresses parasitic reactions.
What are the key performance metrics achieved?
The modified zinc anodes achieve 99.7% Coulombic efficiency, ~30 times longer operation lifetime, and the ZHSs deliver 20,000-cycle stability with improved rate capability.
What is the significance of this work for energy storage?
This work provides a scalable interface engineering strategy to achieve ultrastable and fast-kinetics zinc anodes, advancing the practical application of zinc-ion hybrid supercapacitors for high-energy and high-power storage.
What is the role of β-cyclodextrin in the electrolyte?
β-cyclodextrin grafted with sulfobutyl groups acts as a trace additive that adsorbs on the zinc anode and self-assembles into an interconnecting molecular network, creating anion-trapping cavities and zincophilic sites that regulate zinc deposition.
Related Technical Papers & Translations
Direct Repair of the Crystal Structure and Coating Surface of Spent LiFePO4 Materials Enables Superfast Li-Ion Migration
The rapid accumulation of spent LiFePO4 (LFP) cathodes from retired lithium-ion batteries necessitates the development of effective and environmental-friendly recycling strategies. In this context, direct regeneration has emerged as a promising approach for reclaiming LFP cathode materials, offering a streamlined pathway to restore their electrochemical functionality. We report an integrated regeneration protocol that simultaneously repairs the degraded crystal structure and reconstructs the damaged carbon coating in spent LFP. The regenerated cathode material had superfast lithium-ion diffusion kinetics and a stable cathode–electrolyte interface, giving a remarkable rate capability with specific capacities of 122 mAh g−1 at 5C and 106 mAh g−1 at 10C (1C = 170 mA g−1). It also maintained capacities of 110.7 mAh g−1 (5C) and 84.1 mAh g−1 (10C) after 400 cycles. It could be used in harsh environments and could be stably cycled at subzero temperatures (−10 and −20 °C) and in solid-state electrolyte batteries. Life cycle assessment combined with economic evaluation using the EverBatt model reveals that this direct regeneration approach has high economic and environmental benefits.
Oxide Semiconductor for Advanced Memory Architectures: Atomic Layer Deposition, Key Requirement and Challenges
Oxide semiconductors (OSs), introduced by the Hosono group in the early 2000s, have evolved from display backplane materials to promising candidates for advanced memory and logic devices. The exceptionally low leakage current of OSs and compatibility with three-dimensional (3D) architectures have recently sparked renewed interest in their use in semiconductor applications. This review begins by exploring the unique material properties of OSs, which fundamentally originate from their distinct electronic band structure. Subsequently, we focus on atomic layer deposition (ALD), a core technique for growing excellent OS films, covering both basic and advanced processes compatible with 3D scaling. The basic surface reaction mechanisms—adsorption and reaction—and their roles in film growth are introduced. Furthermore, material design strategies, such as cation selection, crystallinity control, anion doping, and heterostructure engineering, are discussed. We also highlight challenges in memory applications, including contact resistance, hydrogen instability, and lack of p-type materials, and discuss the feasibility of ALD-grown OSs as potential solutions. Lastly, we provide an outlook on the role of ALD-grown OSs in memory technologies. This review bridges material fundamentals and device-level requirements, offering a comprehensive perspective on the potential of ALD-driven OSs for next-generation semiconductor memory devices.
Laser powder bed fusion of biodegradable Zn-4Cu alloy: Processing, microstructure and properties
Zn's natural degradability and biocompatibility make it a promising candidate for implants, however, its mechanical properties remain insufficient for bone applications. In this study, the performance of Zn was enhanced by developing Zn-Cu alloys via laser powder bed fusion (LPBF). Optimal LPBF parameters for forming stable tracks were achieved by adjusting laser power and scanning speed. Under optimized conditions of 100 W and 100 mm/s, high-density (99.58%) Zn-Cu alloys with improved hardness (68.2HV) and yield strength (160 MPa) were achieved. These improvements are attributed to solid solution strengthening, segregation strengthening, and grain refinement. The Zn-Cu alloys also demonstrated favorable degradation behavior, with a rate of 0.16 mm/year. This degradation is primarily driven by micro-galvanic corrosion between the CuZn5 phase and Zn matrix, along with refined grains and increased grain boundary density. This work demonstrates a viable strategy for fabricating Zn-based implants with enhanced structural integrity and mechanical performance via LPBF.