Key Takeaways & Executive Findings
- •• • Optimal Tb3+ single-doping concentration in LBSO is 37%, but co-doping with 20% Gd3+ raises it to 50%, directly demonstrating suppression of concentration quenching and enabling higher activator loading for increased luminescence yield. • • The LBSO:20%Gd3+,50%Tb3+ sample achieves 542 nm emission intensity 2.22 times that of the 37%Tb3+ single-doped sample, indicating a substantial enhancement in photoluminescence output critical for scintillator sensitivity. • • Scintillation efficiency of the optimized glass is 38% relative to BGO, and X-ray imaging resolution exceeds 20 lp mm−1, positioning it as a competitive candidate for high-resolution X-ray detection applications. • • Gd3+-Tb3+ energy transfer efficiency reaches up to 80%, confirming efficient sensitization; combined with cluster dispersion, this dual mechanism provides a design strategy for enhancing luminescence in rare-earth-doped glasses.
Abstract
Gd3+-sensitized Tb3+-based glasses are high light-yield scintillators. Energy transfer sensitization between Gd3+ and Tb3+ is well-recognized. Gd3+ ions are also found to typically modulate the interionic distances of Tb3+ ions; however, the mechanism why this effect enhances the latter’s photoluminescence still remains unclear. This work focuses on Gd3+, Tb3+ co-doped La2O3-B2O3-SiO2 (LBSO), first demonstrating Tb3+ clusters via spectroscopy. LBSO’s optimal Tb3+ single-doping concentration is 37%, rising to 50% with 20% Gd3+. The LBSO:20%Gd3+,50%Tb3+ sample exhibits a 542 nm emission intensity 2.22 times that of the 37%Tb3+ single-doped sample, 38% scintillation efficiency (vs. BGO), and >20 lp mm−1 X-ray resolution. The introduction of Gd3+ increases the interionic distance between Tb3+ ions within the clusters, thereby suppressing the concentration quenching effect and enhancing the fluorescence emission. We propose this mechanism as “cluster-dispersion sensitization effect”. This effect was further confirmed in other glass systems (LBSO:Lu3+, Tb3+, LBSO:Y3+, Tb3+, Bi-based:Lu3+, Tb3+, etc.). Spectroscopic analysis shows Gd3+-Tb3+ energy transfer efficiency up to 80%. In conclusion, Gd3+ synergistically enhances Tb3+ fluorescence via both effects. These findings not only fully elucidate the sensitization mechanism of Gd3+ ions in Gd3+, Tb3+ co-doped scintillating glasses but also provide new insights for researching the manipulation of activator ion clusters in luminescent materials. In search for novel scintillators, cluster-dispersion sensitization effect may greatly improve their spatial resolution via intrinsic architectures design in glasses, ceramics, thin films, and nanoparticles.
1. Introduction
Scintillation materials converting high-energy radiation into visible photons underpin advances in high-energy physics, non-destructive testing, and nuclear medicine. Glass scintillators offer superior preparation efficiency and composition tunability, yet their performance is often limited by activator concentration quenching. Tb3+-doped glasses emit green light near 540 nm under X-ray excitation, but the millisecond-scale 4f-4f transition lifetime restricts them to slow detection scenarios. To boost luminescence, Gd3+ is conventionally added as a sensitizer, exploiting spectral overlap between Gd3+ emission (312 nm) and Tb3+ absorption (302–317 nm). However, the role of Gd3+ in modulating Tb3+ spatial distribution and its impact on concentration quenching has remained unresolved.
This study addresses that gap by systematically investigating Gd3+, Tb3+ co-doped La2O3-B2O3-SiO2 (LBSO) glasses. Through spectroscopic evidence, we demonstrate that Gd3+ disperses Tb3+ clusters, increasing interionic distances and suppressing concentration quenching—a mechanism termed 'cluster-dispersion sensitization effect.' This effect, combined with efficient energy transfer (up to 80%), enables a 2.22-fold enhancement in emission intensity and a 38% scintillation efficiency relative to BGO, with X-ray resolution exceeding 20 lp mm−1. These findings provide a new design principle for high-performance scintillating glasses and other luminescent materials.
Loading authentic research manuscript (Pages 1–5)...
Fazheng Huang, Zhenli Lin, Qingyi Liu, Dongfeng Xue, Yan Yu, Ying Ding, Lingyun Li (2026). Gd3+ Synergistic Sensitization in Tb3+-Doped LBSO Glasses: Influence of Cluster Dispersion and Energy Transfer on Luminescence and X-ray Detection. SCIENCE CHINA Materials. https://doi.org/10.1007/s40843-025-4025-y
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 behind the enhanced Tb3+ luminescence when co-doping with Gd3+?
Gd3+ ions increase the interionic distance between Tb3+ ions within clusters, suppressing concentration quenching. Additionally, Gd3+ acts as a sensitizer via energy transfer (efficiency up to 80%) to Tb3+. This dual effect is termed 'cluster-dispersion sensitization effect.'
How does the optimized glass composition compare to standard scintillators like BGO?
The optimized LBSO:20%Gd3+,50%Tb3+ glass exhibits a scintillation efficiency of 38% relative to BGO, and an X-ray imaging resolution exceeding 20 lp mm−1, making it a promising candidate for high-resolution X-ray detection.
What are the optimal doping concentrations for Tb3+ and Gd3+ in LBSO glasses?
The optimal Tb3+ single-doping concentration is 37%, but with 20% Gd3+ co-doping, the Tb3+ concentration can be increased to 50% without concentration quenching, leading to enhanced emission.
Is the cluster-dispersion effect observed in other glass systems?
Yes, the effect was confirmed in other systems such as LBSO:Lu3+, Tb3+, LBSO:Y3+, Tb3+, and Bi-based:Lu3+, Tb3+, indicating its generality in rare-earth-doped glasses.
What is the energy transfer efficiency between Gd3+ and Tb3+ in this system?
Spectroscopic analysis shows the Gd3+-Tb3+ energy transfer efficiency is up to 80%, which significantly contributes to the enhanced Tb3+ luminescence.
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.