Key Takeaways & Executive Findings
- •• • The MT@MX heterojunction with stepped BIEF reduces LiPSs migration energy barriers, as evidenced by a capacity of 800 mAh g⁻¹ at a high sulfur loading of 6.4 mg cm⁻², demonstrating practical viability for high-energy-density cells. • • Long-term cycling at 0.5 C shows a capacity degradation rate of only 0.078% per cycle over 300 cycles, indicating exceptional stability critical for commercial deployment. • • The multi-interface design enhances LiPSs adsorption and catalysis, enabling uniform lithium deposition and dendrite suppression, which is essential for safe and long-life LSBs. • • The facile redox synthesis of MT@MX offers a scalable route to fabricate advanced separator catalysts, potentially reducing manufacturing costs compared to complex multi-step processes.
Abstract
Lithium-sulfur batteries (LSBs) are recognized as a leading candidate for next-generation energy storage due to their high theoretical specific capacity (1675 mAh g⁻¹). However, the shuttle effect of lithium polysulfides (LiPSs) severely limits cycle life and energy efficiency. Here, we report a multi-interface engineering strategy employing a MnO₂-TiO₂@Ti₃C₂ MXene (MT@MX) heterojunction, synthesized via a facile redox reaction between MXene and KMnO₄, to modulate bidirectional polysulfide conversion. The 2D structure with high conductivity and abundant heterogeneous interfaces facilitates fast ion/electron transfer, reduces reaction energy barriers, and enhances adsorption via d-band center effects. The stepped built-in electric field (BIEF) in MT@MX lowers the migration energy barrier of LiPSs from catalytic MXene to TiO₂ and then to adsorptive MnO₂, enabling reversible migration across multi-interfaces. Optimized heterointerfaces synergistically integrate adsorption, diffusion, and catalytic conversion, yielding excellent cycling stability even at a high sulfur loading of 6.4 mg cm⁻². This work demonstrates that constructing heterojunctions with stepped BIEF offers a feasible approach to modulate interfacial diffusion and provides a new design strategy for high-performance LSB electrocatalysts.
1. Introduction
The commercialization of lithium-sulfur batteries (LSBs) has been persistently hindered by the shuttle effect, wherein soluble lithium polysulfides (LiPSs) migrate from the cathode to the anode, causing active material loss, rapid capacity fade, and low coulombic efficiency. Conventional physical barriers and simple catalytic layers have shown limited efficacy due to insufficient adsorption and slow conversion kinetics. The challenge lies in designing a catalyst that simultaneously anchors LiPSs, accelerates their redox reactions, and facilitates uniform lithium deposition.
This work introduces a multi-interface engineering approach using a MnO₂-TiO₂@Ti₃C₂ MXene (MT@MX) heterojunction as a separator catalyst. The stepped built-in electric field (BIEF) created by the heterointerfaces is strategically designed to lower the migration energy barrier of LiPSs, promoting their directional transport and conversion. By integrating adsorptive MnO₂, catalytic TiO₂, and conductive MXene, the MT@MX architecture addresses the bottlenecks of LiPSs shuttling and sluggish kinetics, offering a promising pathway toward high-performance, practical LSBs.
Loading authentic research manuscript (Pages 1–5)...
Junliang Xu, Chuan Shi, Shunxian Yu, Tianlong Lan, Chaoyue Zhang, Xiaoxian Zhao, Zhipeng Ma, Yufei Zhao, Jinqiang Zhang, Hao Yan, Shuangqiang Chen, Qiang Li, Jianjun Song (2026). Multi-Interface Engineering Modulated Bidirectional Polysulfide Conversion for Advanced Lithium-Sulfur Batteries. SCIENCE CHINA Materials. https://doi.org/10.1007/s40843-026-4260-5
Research & Educational Purpose Only: The translations, structured abstracts, analytical annotations, and data reports provided by SinoGreenTechare 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. SinoGreenTech 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 specific role of the stepped built-in electric field (BIEF) in enhancing polysulfide conversion kinetics?
The stepped BIEF, formed by the heterojunction between MnO₂, TiO₂, and MXene, creates a gradient in electrostatic potential that lowers the migration energy barrier for lithium polysulfides (LiPSs). This facilitates directional transport from the catalytic MXene terminal to TiO₂ and then to the adsorptive MnO₂ terminal, thereby accelerating redox reactions and improving overall kinetics. The effect is quantified by a capacity of 800 mAh g⁻¹ at a high sulfur loading of 6.4 mg cm⁻², indicating efficient conversion even under demanding conditions.
How does the MT@MX modified separator compare to conventional separators in terms of long-term cycling stability?
The MT@MX modified separator demonstrates a capacity degradation rate of only 0.078% per cycle over 300 cycles at 0.5 C, which is significantly lower than typical values for conventional polypropylene separators (often >0.1% per cycle). This improvement is attributed to the synergistic adsorption-catalysis effect of the heterojunction, which suppresses the shuttle effect and maintains active material integrity, leading to enhanced cycle life.
What are the scalability and cost implications of the MT@MX synthesis method?
The MT@MX heterojunction is fabricated via a facile redox reaction between MXene and KMnO₄, which is a simple, one-step process that can be easily scaled up. MXene precursors are commercially available, and KMnO₄ is inexpensive, making the overall synthesis cost-effective. Compared to complex multi-step catalyst preparations, this method offers a practical route for industrial production of high-performance separator coatings.
How does the MT@MX heterojunction address the issue of lithium dendrite growth?
The MXene component in MT@MX promotes uniform lithium deposition by providing a conductive and nucleophilic surface, which is verified by SEM observations. This uniform deposition suppresses dendrite formation, enhancing battery safety and cycle stability. The long-term cycling data (0.078% degradation per cycle) indirectly confirms the effectiveness of dendrite suppression, as dendrite-induced short circuits would cause abrupt capacity drops.
What is the practical significance of achieving 800 mAh g⁻¹ at a high sulfur loading of 6.4 mg cm⁻²?
High sulfur loading is essential for achieving high energy density in practical LSBs. A capacity of 800 mAh g⁻¹ at 6.4 mg cm⁻² corresponds to an areal capacity of approximately 5.1 mAh cm⁻², which exceeds the target for commercial viability (typically >4 mAh cm⁻²). This demonstrates that the MT@MX separator can enable high-energy-density cells without compromising cycling stability, making it a promising candidate for real-world applications.
Related Chinese Research & Cross-Citations
Ammonium Vanadate Cathodes in Aqueous Zinc-Ion Batteries: Design Strategies and Research Progress
Aqueous zinc-ion batteries (AZIBs) offer a compelling combination of high safety, environmental compatibility, and abundant zinc resources, positioning them as viable candidates for grid-scale energy storage. Their practical deployment, however, is constrained by cathode materials that suffer from structural degradation, sluggish Zn2+ diffusion, and inadequate electronic conductivity. Ammonium vanadates (AVOs) have emerged as high-performance cathodes owing to their layered or tunneled frameworks, which accommodate reversible Zn2+ (de)intercalation with diffusion coefficients superior to conventional vanadium oxides. This review systematically examines recent advances in AVO cathodes for AZIBs, correlating morphological variations—including nanowires, nanobelts, and microflowers—with electrochemical characteristics. The analysis establishes structure–performance relationships that govern capacity retention, rate capability, and cycling stability. Key optimization strategies are critically assessed: defect engineering to enhance electronic conductivity and active site density, interlayer spacing modulation via pre-intercalated cations or structural water to facilitate Zn2+ transport, and composite construction with conductive carbonaceous or polymeric matrices to mitigate dissolution and improve mechanical integrity. Despite these advances, challenges persist in achieving long-term cycling stability (>10,000 cycles) and high areal mass loading (>10 mg cm-2) required for commercial viability. The review concludes by outlining future research directions, including operando characterization of degradation mechanisms and scalable synthesis routes for AVO cathodes in practical AZIB configurations.
Microenvironment-responsive therapeutic platforms: Innovations for spinal cord injury repair
Spinal cord injury (SCI) remains a formidable clinical challenge due to the complex, dynamic lesion microenvironment that impedes axonal regeneration and functional recovery. This highlight examines a microenvironment-responsive therapeutic platform integrating microneedle delivery, ferroptosis modulation, and hydrogen therapy. The platform leverages the pathological hallmarks of SCI—oxidative stress, iron dyshomeostasis, and lipid peroxidation—to achieve spatiotemporally controlled cargo release. By combining microneedle arrays for minimally invasive intraparenchymal administration with hydrogen-releasing biomaterials, the system addresses the dual bottlenecks of poor drug penetration across the blood-spinal cord barrier and insufficient neutralization of reactive oxygen species. Ferroptosis inhibition is achieved through iron chelation and glutathione peroxidase 4 (GPX4) stabilization, while hydrogen gas scavenges hydroxyl radicals and peroxynitrite. This multimodal strategy attenuates secondary injury cascades, reduces glial scar formation, and promotes neural stem cell differentiation. The work is supported by the National Natural Science Foundation of China (82574518) and the Talent Cultivation Project of Paring Academicians with Young Talents in higher education institutions in Zhejiang. The authors declare no conflict of interest. This highlight underscores the translational potential of microenvironment-responsive platforms for SCI repair, emphasizing the need for rigorous preclinical validation and scalable manufacturing.
Dual-Site Adsorption over Phosphorus-Doped Copper Oxide for Efficient CO2 Electroreduction to Ethylene
Electroreduction of CO2 to ethylene offers a promising route for renewable electricity storage, yet achieving high ethylene selectivity at industrial current densities remains challenging due to the large energy barrier for C–C coupling. Here, we report a “MOF-assisted in situ doping” strategy to introduce the oxophilic nonmetal phosphorus (P) into the copper oxide (CuO) lattice, constructing a localized Cu–P dual-site adsorption configuration for the key *OCCHO intermediate. The optimized catalyst delivers an impressive Faradaic efficiency of 64.6% for ethylene with a partial current density of 646 mA cm-2. Comprehensive structural characterizations demonstrate that P mainly occupies Cu sites, generating abundant lattice defects and oxygen vacancies. In situ synchrotron infrared spectroscopy and theoretical calculations reveal that P doping modulates the electronic structure of Cu, optimizes the binding energies of *CO and *CHO, and stabilizes *OCCHO via P–O/Cu–C dual-site adsorption, thereby significantly lowering the asymmetric C-C coupling energy barrier to 0.74 eV. This work highlights a dual-site microenvironment regulation strategy for CO2-to-ethylene electroreduction.
Hydrophilic Single-Atom Interface Unlocks Low-Potential CO Removal on Pt in PEMFCs
Proton exchange membrane fuel cells (PEMFCs) fed with reformate hydrogen suffer severe anode poisoning by trace CO, necessitating high CO electrooxidation potentials that degrade performance and durability. This work introduces a Pt@CrSA-N-C anode catalyst featuring a hydrophilic Cr single-atom interface that simultaneously weakens CO adsorption on Pt via electronic regulation and promotes water activation, thereby lowering the CO oxidation onset potential to approximately 0.13 V vs. RHE. The onset potential was determined by two independent methods: the first potential at which the background-corrected current exceeds 0 mA cm-2 during CO oxidation reaction tests in a three-electrode system, and the potential at which the forward scan current exceeds the N2 background current in CO-stripping voltammetry. The catalyst achieves a maximum power density under 100 ppm CO that surpasses reported advanced catalysts, as compiled in Table S5. Structural, spectroscopic, and electrochemical characterizations collectively establish a coherent rationale for the hydrophilic single-atom interface strategy. This approach addresses the longstanding trade-off between CO tolerance and Pt utilization, offering a viable route for low-potential CO removal in practical PEMFC anodes.
An Ionoelastomer-Based Bioinspired Wearable Electronics with Tele-Perception and Tactile Sensation for Machine Learning-Assisted Rehabilitation Management
Comprehensive assessment of rehabilitation efficiency is essential for designing appropriate training programs for better musculoskeletal functional recovery. Existing contact-receptor-dependent rehabilitation assessment systems mostly focus on assessing the restoration of muscle function by evaluating grip strength or joint flexion angle; however, parameters reflecting neuromuscular synergistic function are always overlooked. Herein, we develop an ionoelastomer-based soft artificial electroreceptor (SAER) that integrates tele-perception and tactile sensation to track the rehabilitation process, collecting signals related to approaching speed and grip strength sequentially. The SAER uses polyurethane ionoelastomer incorporated with quasi-solid conductive salt as the electric field receptor, and is integrated on a rehabilitation-training ball after assembly to establish an untethered detection device; this enables the remote capture of hand approaching parameter within a 9 cm range, followed by the quantification of grip strength when contacting and grasping. Furthermore, a data-driven assessment system is established by integrating machine learning, which accurately classifies rehabilitation efficiency into six levels; it supports for rehabilitation evaluation and training programs adjustment. Overall, the SAER-based rehabilitation management system establishes a paradigm that synergistically evaluating parameters corresponding to neuromuscular functional restoration and holds strong potential for home-based active rehabilitation for minimizing dependence on frequent clinical supervision.
Microwave-Absorbing Materials with Strong Environmental Adaptability for Corrosion Protection, Anti-Icing, and Thermal Management
Microwave-absorbing materials (MAMs) deployed on naval vessels, aerospace vehicles, and critical electronic systems face coupled electromagnetic, marine salt-spray corrosion, and extreme-temperature loads that legacy single-function absorbers cannot withstand. This review consolidates progress on three environmentally adaptive MAM classes: corrosion-protective, anti-icing, and thermal-management absorbers. The electromagnetic loss and impedance-matching fundamentals are first established, then the synergistic mechanisms, design strategies, and characterization protocols for each class are examined against representative material systems and their measured performance. The analysis identifies a shared design logic—multiscale hierarchical architecture, interfacial polarization engineering, and multifunctional phase integration—while distinguishing the divergent protection mechanisms: barrier and passivation effects for corrosion, surface-energy and latent-heat regulation for anti-icing, and phonon–electron transport decoupling for thermal management. Persistent bottlenecks include the trade-off between impedance matching and protective-layer density, the absence of standardized coupled-field test protocols, and the scarcity of long-term salt-spray and thermal-cycling durability data. Future directions are delineated: intelligent self-adaptive absorbers, multiphysics-coupled simulation frameworks, and environmentally benign multifunctional integration. The review provides a theoretical and technical basis for the design, construction, and engineering scale-up of next-generation high-performance absorbers for aerospace, electronic, and marine equipment.