Key Takeaways & Executive Findings
- •• • Structural randomization reduces normalized higher-order diffraction energy to −3.93 dB, effectively suppressing ghost images in optical windows. • • The most randomized Cu mesh film achieves an ultra-low sheet resistance of 3.31 Ω/sq and high visible light transmittance of 88.7% at 550 nm, yielding an exceptional figure of merit (FoM=913.69). • • EMI shielding effectiveness averages 33.18 dB across the X-band (8–12 GHz), meeting robust shielding requirements for sensitive electronics. • • Imaging resolution degrades minimally from 80.6 to 71.8 lp/mm, demonstrating that randomization preserves optical quality while enhancing EMI shielding.
Abstract
This work presents a cracked template and vacuum metal evaporation strategy for fabricating structurally randomized copper (Cu) mesh films. Regulating the internal stress distribution within the coating during template cracking enables controlled fabrication of Cu mesh films with varying discrete degrees of mesh aperture area and distinct probability distributions of metal line inclination. The influence of structural parameter randomization on properties was systematically investigated, encompassing higher-order diffraction energy homogenization, optoelectronic performance, and electromagnetic interference shielding effectiveness (EMI SE). Results demonstrate that increasing structural randomization effectively suppresses higher-order diffraction energy, achieving a reduction to −3.93 dB in normalized higher-order diffraction energy. Furthermore, the Cu mesh film exhibited minimal degradation on imaging system performance, with resolution decreasing only marginally from 80.6 to 71.8 lp/mm. Simultaneously, the most randomized Cu mesh film demonstrates an ultra-low sheet resistance (3.31 Ω/sq), high visible light transmittance (88.7% at 550 nm), an exceptional figure of merit (FoM=913.69), and robust EMI SE within the X-band (average SE of 33.18 dB). These findings underscore that metal mesh films incorporating structural randomization offer an effective strategy for enhancing EMI shielding in high-performance optoelectronic imaging systems.
1. Introduction
Conventional periodic metal mesh designs suffer from concentrated higher-order diffraction energy, which induces ghost images and degrades imaging quality in transparent EMI shielding windows. While various strategies such as petal-shaped, honeycomb, and ring arrays have been explored, they often involve complex fabrication or fail to fully suppress diffraction artifacts. The bottleneck remains achieving a balance between high optical transparency, minimal imaging distortion, and effective EMI shielding.
This work introduces a cracked template and vacuum metal evaporation method to fabricate structurally randomized Cu mesh films. By controlling internal stress during template cracking, the mesh aperture areas and line inclinations are randomized, which homogenizes higher-order diffraction energy. The resulting films exhibit ultra-low sheet resistance, high transmittance, and robust EMI SE, while causing only slight degradation in imaging resolution. This approach directly addresses the trade-off between optical performance and shielding effectiveness, offering a scalable and cost-effective solution for high-performance optoelectronic systems.
Loading authentic research manuscript (Pages 1–5)...
Yongmao Guan, Liqing Yang, Chen Guo, Mingde Chen, Qinfang Chen, Pengfei Wang (2026). Controllable Structurally Randomized Cu Mesh Films for EMI-Shielded Optical Windows with Slight Imaging Quality Degradation. SCIENCE CHINA Materials. https://doi.org/10.1007/s40843-025-3901-2
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 mechanism by which structural randomization suppresses higher-order diffraction energy in Cu mesh films?
Randomizing the mesh aperture areas and line inclinations disrupts the periodic lattice that causes constructive interference at higher diffraction orders. This spreads the diffracted energy into a continuum, reducing the peak intensity of higher-order spots. The study reports a reduction to −3.93 dB in normalized higher-order diffraction energy, effectively suppressing ghost images.
How does the randomization affect the electrical and optical performance of the Cu mesh films?
The most randomized film achieves an ultra-low sheet resistance of 3.31 Ω/sq and a high visible light transmittance of 88.7% at 550 nm, resulting in an exceptional figure of merit (FoM=913.69). This indicates that randomization does not compromise conductivity or transparency, making it suitable for transparent EMI shielding applications.
What is the EMI shielding effectiveness of the randomized Cu mesh films in the X-band, and how does it compare to conventional periodic meshes?
The randomized Cu mesh films exhibit an average EMI SE of 33.18 dB across the X-band (8–12 GHz). This level of shielding is comparable to or better than conventional periodic meshes, while offering improved optical performance due to reduced diffraction artifacts.
What is the impact of structural randomization on imaging quality, as quantified by the modulation transfer function (MTF)?
The imaging resolution, measured via MTF, decreases only marginally from 80.6 to 71.8 lp/mm, indicating that the randomization causes slight degradation in imaging quality. This is a significant improvement over periodic meshes, which often cause more severe ghosting and resolution loss.
What are the scalability and cost implications of the cracked template and vacuum metal evaporation method for industrial production?
The method leverages low-cost cracked templates and standard vacuum evaporation, which are scalable to large-area substrates. The controlled stress regulation during cracking allows reproducible fabrication. While specific cost data are not provided, the process is compatible with roll-to-roll manufacturing, suggesting potential for cost-effective mass production.
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.