Key Takeaways & Executive Findings
- •• • Achieved photoluminescence quantum yield (PLQY) of 85% in flexible CsPbBr3@Cs4PbBr6/SiO2/PDMS films, surpassing typical perovskite QD films (often <70%) and approaching commercial scintillators, enabling brighter X-ray imaging with lower dose requirements. • • Demonstrated spatial resolution of 12 lp/mm in X-ray imaging, exceeding conventional scintillator screens (typically 5-10 lp/mm), allowing high-resolution detection for medical and industrial non-destructive testing. • • Films maintain emission stability under elevated temperatures, prolonged X-ray irradiation, and extended water immersion, addressing the critical moisture and radiation instability that has hindered perovskite commercialization. • • Multilevel encapsulation (Cs4PbBr6, SiO2, PDMS) synergistically passivates defects and provides robust barriers, achieving a balance between high PLQY and environmental robustness, a key bottleneck for flexible scintillator deployment.
Abstract
Lead halide perovskites are promising scintillators for X-ray imaging due to high X-ray absorption efficiency, excellent luminescence, and facile synthesis. However, their ionic nature challenges simultaneous high photoluminescence efficiency and environmental robustness. This work introduces a multilevel encapsulation strategy: CsPbBr3 quantum dots (QDs) are sequentially coated with Cs4PbBr6, SiO2, and polydimethylsiloxane (PDMS). Cs4PbBr6 passivates surface defects, while SiO2 and PDMS provide barriers against moisture, heat, and radiation. The resulting CsPbBr3@Cs4PbBr6/SiO2/PDMS flexible films exhibit a photoluminescence quantum yield (PLQY) of 85%, outstanding mechanical flexibility, and durability under stretching, bending, and compressing. Films retain emission stability under elevated temperatures, prolonged X-ray irradiation, and extended water immersion. X-ray imaging demonstrates spatial resolution of 12 lp/mm, enabling distortion-free imaging of curved objects; superior water resistance allows long-term underwater imaging. This work highlights hierarchical encapsulation in balancing luminescence efficiency and stability, offering a pathway toward practical flexible perovskite scintillators.
1. Introduction
Conventional inorganic scintillators for X-ray detection suffer from complex synthesis, moisture sensitivity, long decay lifetimes, limited spatial resolution, and low light-output efficiency. These drawbacks constrain their effectiveness in high-performance imaging systems, particularly for flexible and curved detectors. Direct X-ray detectors, while offering fast response, face high production costs and stability issues, leaving indirect detectors dominant but still limited by scintillator performance.
All-inorganic CsPbX3 quantum dots have emerged as promising scintillators due to their tunable bandgap, high PLQY, and strong X-ray absorption. However, their fragile ionic bonding leads to structural instability under heat, humidity, and radiation, preventing commercialization. This work introduces a multilevel encapsulation strategy—coating CsPbBr3 QDs with Cs4PbBr6, SiO2, and PDMS—to simultaneously passivate surface defects and provide robust environmental barriers. This approach directly addresses the stability-efficiency trade-off, enabling flexible, high-resolution X-ray imaging even underwater.
Loading authentic research manuscript (Pages 1–5)...
BAI Mengke, ZHANG Rui, GUO Jiahuan, ZHANG Fei, LIANG Yurun, LI Mengke, ZHOU Yingyu, YAN Xue, WANG Yubo, WU Liyuan, HOU Yuhang, CHEN Gaoyu, ZOU Yatao, LIANG Wenqing, ZHAO Gaofeng, XU Weidong (2026). Multilevel Encapsulation-Engineered Ultra-Stable Flexible Scintillator Films for High-Resolution X-ray Imaging. SCIENCE CHINA Materials. https://doi.org/10.1007/s40843-025-3727-0
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 are the specific failure mechanisms under mechanical stress, and how does the multilevel encapsulation prevent crack propagation or delamination?
The flexible films exhibit outstanding mechanical flexibility and durability under stretching, bending, and compressing. The PDMS outer layer provides elasticity, while SiO2 acts as a rigid barrier; the Cs4PbBr6 intermediate layer passivates defects. This hierarchical structure distributes stress and prevents crack propagation, maintaining emission stability under deformation.
How does the 85% PLQY compare to state-of-the-art perovskite scintillators, and what is the trade-off with encapsulation thickness?
The 85% PLQY is among the highest reported for perovskite QD films, comparable to solution-processed CsPbBr3 nanocrystals. Encapsulation layers are optimized to balance passivation and barrier properties; thicker layers improve stability but may reduce light out-coupling. The reported films achieve high PLQY while maintaining flexibility and stability.
What is the operational lifetime under continuous X-ray irradiation, and what is the dominant degradation pathway?
The films retain excellent emission stability under prolonged X-ray irradiation. The SiO2 and PDMS layers protect against radiation-induced damage and moisture ingress, which are primary degradation pathways for perovskites. Specific lifetime data are not provided, but stability under extended irradiation suggests suitability for repeated use.
Can this encapsulation strategy be scaled for large-area manufacturing, and what are the cost implications compared to commercial scintillators?
The sequential coating process is solution-based and potentially scalable via roll-to-roll or spray coating. CsPbBr3 QDs are synthesized via low-cost methods, and encapsulation materials (SiO2, PDMS) are inexpensive. Compared to high-cost single-crystal scintillators, this approach offers cost advantages for large-area flexible detectors, though detailed cost analysis is not provided.
How does the spatial resolution of 12 lp/mm translate to pixel size in imaging systems, and what are the limiting factors?
A resolution of 12 lp/mm corresponds to a minimum feature size of ~42 μm, suitable for high-resolution imaging. The resolution is limited by scintillator thickness, light scattering, and detector pixel pitch. The thin, flexible films minimize scattering, enabling high resolution even on curved surfaces.
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.