Science China Materials最新文献

{"title":"DNA-directed adhesion of a sono-activatable hydrogel to oral leukoplakia lesion for cGAS-STING pathway associated-immunotherapy","authors":"Yiming Kong \u0000 (,&nbsp;),&nbsp;Yao Xu \u0000 (,&nbsp;),&nbsp;Dantong Zheng \u0000 (,&nbsp;),&nbsp;Hao Wang \u0000 (,&nbsp;),&nbsp;Yishan Li \u0000 (,&nbsp;),&nbsp;Qirong Tang \u0000 (,&nbsp;),&nbsp;Yong Hu \u0000 (,&nbsp;)","doi":"10.1007/s40843-026-4134-6","DOIUrl":"10.1007/s40843-026-4134-6","url":null,"abstract":"<div><p>Oral leukoplakia (OLK) carries a risk of malignant transformation. While adhesive hydrogels enhance drug retention in the dynamic and moist oral cavity, their inability to achieve lesion-specific adhesion or precision therapy restricts precision medicine applications. To address this, we synthesize DNA hydrogels through co-crosslinking of thiolated gelatin and thiolated oligonucleotide via disulfide bonds. During crosslinking, Mn²⁺ and chlorin e6 (Ce6) are incorporated through thiol-metal coordination and physical entrapment within the molecular network, respectively, yielding sono-activatable DNA hydrogels. To confer site-specific adhesion, low-frequency ultrasound (LFUS) is employed to anchor complementary oligonucleotide onto the lesion surface, enabling the bioadhesion of DNA hydrogels through base pairing. Under high-frequency ultrasound (HFUS), the sonosensitizer Ce6 generates substantial reactive oxygen species, triggering the mitochondrial DNA (mtDNA) release within hyperproliferative epithelial cells. Concurrent HFUS accelerates Mn²⁺ release from the hydrogel, potentiating cGAS recognition of cytosolic mtDNA and activating the cyclic GMP-AMP synthase stimulator of interferon genes (cGAS-STING) pathway. The subsequently matured dendritic cells (DCs) prime naïve T cells to differentiate into cytotoxic T lymphocytes, reversing the immunosuppressive microenvironment in OLK. Interestingly, this therapeutic modality even induces an immunological memory effect to restrain OLK recurrence and impede malignant transformation. Our study introduces the first DNA-directed hydrogel bioadhesion strategy and thus proposes unprecedented cGAS-STING pathway associated-immunotherapy against OLK.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":773,"journal":{"name":"Science China Materials","volume":"69 10","pages":"6530 - 6546"},"PeriodicalIF":7.7,"publicationDate":"2026-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149098168","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A H2O2-triggered NIR chemiluminescence nanoprobe with aggregation-induced emission properties for in vivo inflammation imaging and tumor theranostics","authors":"Junhao Huang \u0000 (,&nbsp;),&nbsp;Lin Yang \u0000 (,&nbsp;),&nbsp;Yufeng Xiao \u0000 (,&nbsp;),&nbsp;Yuxi Li \u0000 (,&nbsp;),&nbsp;Jiachang Huang \u0000 (,&nbsp;),&nbsp;Ben Zhong Tang \u0000 (,&nbsp;),&nbsp;Benzhao He \u0000 (,&nbsp;)","doi":"10.1007/s40843-026-4117-y","DOIUrl":"10.1007/s40843-026-4117-y","url":null,"abstract":"<div><p>The real-time, <i>in situ</i> imaging of hydrogen peroxide (H₂O₂), a key reactive oxygen species implicated in various diseases, remains challenging. This is primarily due to the limitations of existing probes, such as short emission wavelengths and the reliance on external excitation. To address these issues, we developed an H₂O₂-triggered near-infrared (NIR) chemiluminescence (CL) nanoprobe with aggregation-induced emission (AIE) characteristics for <i>in vivo</i> inflammation imaging and tumor theranostics. This nanoprobe, denoted as CPPO@TN NPs, was constructed by co-encapsulating a tailored AIE photosensitizer (TN) with strong NIR emission and high singlet oxygen (¹O₂) generation, a H₂O₂-responsive chemiluminescent substrate (CPPO), and soybean oil (as a retarder) within F-127 micelles. Upon encountering H₂O₂, the nanoprobe undergoes a persistent chemically initiated electron exchange luminescence (CIEEL) process that activates AIEgens, resulting in intense NIR chemiluminescence and sustained ¹O₂ production without the need for external irradiation. Leveraging this mechanism, CPPO@TN NPs achieved highly sensitive and specific imaging of drug-induced liver injury and peritonitis in murine models, with exceptional tissue penetration and signal-to-noise ratio. Furthermore, the nanoprobe facilitated effective self-luminescent imaging and photodynamic therapy of tumors, significantly inhibiting tumor growth in a 4T1 tumor-bearing mouse model. This platform provides an external light excitation-free theranostic strategy for H₂O₂-associated diseases.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":773,"journal":{"name":"Science China Materials","volume":"69 9","pages":"5814 - 5826"},"PeriodicalIF":7.7,"publicationDate":"2026-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148962120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Self-assembled theranostic nanoplatform-mediated calcium-overload for enhanced sonodynamic therapy","authors":"Shasha Zhao \u0000 (,&nbsp;),&nbsp;Qingyan Huang \u0000 (,&nbsp;),&nbsp;Feiyu Yu \u0000 (,&nbsp;),&nbsp;Peng Gu \u0000 (,&nbsp;),&nbsp;Xueli Ye \u0000 (,&nbsp;),&nbsp;Juan Mou \u0000 (,&nbsp;),&nbsp;Huixia Wu \u0000 (,&nbsp;)","doi":"10.1007/s40843-025-4024-1","DOIUrl":"10.1007/s40843-025-4024-1","url":null,"abstract":"<div><p>Although sonodynamic therapy (SDT) exhibits distinctive advantages in antitumor treatment, the robust antioxidant system within tumor tissues reduces the availability of the generated reactive oxygen species and limits its therapeutic efficacy. To address this challenge, we develop a pH/ultrasound-responsive theranostic nanoplatform, designated as Mn-CaCO₃@NGQDs/PAA, through the self-assembly of nitrogen-doped graphene quantum dots (NGQDs), Mn-doped CaCO₃, and polyacrylic acid (PAA). This platform synergistically combines SDT with calcium overload to enhance therapeutic outcomes. Concurrently, Mn-CaCO₃@NGQDs/PAA triggers massive production of singlet oxygen (¹O₂) when exposed to ultrasound irradiation, while the acidic microenvironment prompts sustained release of Ca²⁺ ions, inducing calcium overload. The concomitant elevated ¹O₂ level and calcium overload synergistically amplify oxidative stress within tumor cells, resulting in effective suppression of tumor growth. In addition, Mn-CaCO₃@NGQDs/PAA demonstrates dual-mode T₁/T₂-weighted magnetic resonance imaging performance, facilitating tumor localization. The integration of SDT and calcium overload maximizes therapeutic efficacy, offering a promising strategy for enhanced tumor therapy.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":773,"journal":{"name":"Science China Materials","volume":"69 9","pages":"5769 - 5778"},"PeriodicalIF":7.7,"publicationDate":"2026-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148962119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rapid reconstruction of commercial bulk niobium oxide for highly stable electrochemical uranium extraction in the presence of fluorine","authors":"Kai Hou \u0000 (,&nbsp;),&nbsp;Guo Li \u0000 (,&nbsp;),&nbsp;Xiaochuan Deng \u0000 (,&nbsp;),&nbsp;Honghao Zhang \u0000 (,&nbsp;),&nbsp;Xue Jiang \u0000 (,&nbsp;),&nbsp;Wenli Zhou \u0000 (,&nbsp;),&nbsp;Rong He \u0000 (,&nbsp;),&nbsp;Wenkun Zhu \u0000 (,&nbsp;)","doi":"10.1007/s40843-025-4185-6","DOIUrl":"10.1007/s40843-025-4185-6","url":null,"abstract":"<div><p>Electrochemical uranium extraction in fluorine-containing nuclear wastewater is important for the recovery of nuclear fuel, whereas the current electrode material faces limitations of large-scale synthesis and long-term stability, considering the practical application. Herein, the bulk monoclinic Nb₂O_5−<i>x</i> (H-Nb₂O_5−<i>x</i>) synthesized from commercial bulk material was demonstrated as a highly active and robust material for electrochemical uranium extraction in fluorine-containing nuclear wastewater. In H-Nb₂O_5−<i>x</i>, the intrinsic active pairs of the low-valent Nb⁴⁺ and the compact oxygen structure can strongly bind with the dominant uranyl fluoride. Accordingly, the H-Nb₂O_5−<i>x</i> exhibited a remarkable uranium efficiency of 99.1% in 30 g L⁻¹ of fluorine. More importantly, in the experiment of 10-L of real nuclear wastewater, the bulk H-Nb₂O_5−<i>x</i> materials exhibited a 40-day stability for electrochemical uranium extraction. After the extraction, the concentration of uranium decreased from 1372.3 to 0.93 mg L⁻¹. Our work provides a robust bulk material for long-term industrial application of electrochemical uranium extraction.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":773,"journal":{"name":"Science China Materials","volume":"69 9","pages":"5720 - 5727"},"PeriodicalIF":7.7,"publicationDate":"2026-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148962130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of Biotin-DFYIGSRGD hydrogel in the construction of an islet culture platform","authors":"Sifan Ai \u0000 (,&nbsp;),&nbsp;Yue Wang \u0000 (,&nbsp;),&nbsp;Lei Du \u0000 (,&nbsp;),&nbsp;Lei Liu \u0000 (,&nbsp;),&nbsp;Zhimou Yang \u0000 (,&nbsp;),&nbsp;Gang Hu \u0000 (,&nbsp;)","doi":"10.1007/s40843-026-4071-3","DOIUrl":"10.1007/s40843-026-4071-3","url":null,"abstract":"<div><p>The low survival rate and compromised functionality of β cells present significant obstacles in islet transplantation for diabetes management. Recent studies indicate that the sensitivity of β cells to their microenvironment may be a contributing factor for these. In this study, Biotin-^DFYIGSRGD hydrogel (Supragel) was employed to replicate the microenvironment of mouse β cells (MIN6 cells) and human islets, for enhancing cell viability, functionality, and structural integrity. Compared with conventional two-dimensional cell culture methods utilizing cell plates, in the present method, MIN6 cells could adhere to the gel and self-organize into cell spheroids, which resulted in increased synthesis of insulin and glucagon in MIN6 cells. Furthermore, the hydrogel effectively preserved the integrity of human islets and extended their <i>in vitro</i> culture period. This improvement may be attributed to the optimal hardness of the gel, which facilitated cell adhesion and promoted vascularization. Additionally, the gel exhibited sustained <i>in vivo</i> retention over 120 days, undergoing gradual degradation without eliciting significant inflammatory responses. These properties establish it as a promising encapsulation material for pancreatic islet cells or organoids, supporting long-term cell survival, function, and integration with host tissues. The study highlights the potential of Biotin-^DFYIGSRGD hydrogel as an islet culture platform for diabetes treatment.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":773,"journal":{"name":"Science China Materials","volume":"69 9","pages":"5839 - 5847"},"PeriodicalIF":7.7,"publicationDate":"2026-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148962090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Giant optical anisotropy in the edge surfaces of layered crystals: unveiled by direct measurements of out-of-plane optical constants","authors":"Jiao Dong \u0000 (,&nbsp;),&nbsp;Xinhui Hao \u0000 (,&nbsp;),&nbsp;Yimeng Shi \u0000 (,&nbsp;),&nbsp;Dahuai Zheng \u0000 (,&nbsp;),&nbsp;Wei Xin \u0000 (,&nbsp;),&nbsp;Jian-Guo Tian \u0000 (,&nbsp;),&nbsp;Xiao-Qing Yan \u0000 (,&nbsp;)","doi":"10.1007/s40843-026-4149-1","DOIUrl":"10.1007/s40843-026-4149-1","url":null,"abstract":"<div><p>Large optical anisotropy is of paramount importance for efficient light manipulation in optoelectronic devices. Van der Waals layered materials, exhibiting large structural contrast between in-plane and out-of-plane directions, are inherently anisotropic in 3D space. The measurements of their optical constants were limited to the 2D planes. Here, the reflectance spectra of layered MoS₂, NbOCl₂, and WTe₂ crystals are measured directly from their edge and basal surfaces to compare their out-of-plane and in-plane optical constants in the range of 500–1000 nm. The results indicate that their out-of-plane refractive indices are smaller than the in-plane refractive indices. The out-of-plane extinction coefficients of MoS₂ and NbOCl₂ are zero but nonzero for WTe₂, as confirmed by the transient reflection spectroscopies. The nonzero extinction coefficient of WTe₂ arises from the symmetry of the transition dipole moment and density of states, which are determined by the crystal structure. Meanwhile, compared to their in-plane optical constants, the out-of-plane optical constants of MoS₂ and NbOCl₂ exhibit less dispersion, whereas WTe₂ exhibits enhanced out-of-plane dispersion around 2.14 eV. This enhancement is attributed to significant increases in optical transition probability resulting from a larger density of states. These optical parameters indicate giant birefringence (e.g., &gt;1.8 for MoS₂, &gt;0.6 for NbOCl₂, and &gt;0.5 for WTe₂) and linear dichroism (e.g., up to 100% for MoS₂ and NbOCl₂, 40.7% for WTe₂) on the edge surface of layered materials. These results could be used to predict the optical response at arbitrary angles of incidence and are helpful for their application in polarization-related optoelectronic devices.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":773,"journal":{"name":"Science China Materials","volume":"69 9","pages":"5485 - 5493"},"PeriodicalIF":7.7,"publicationDate":"2026-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148962091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biomimetic design of Turing-type grain boundary defects in copper catalysts for boosting CO2 electroreduction to multi-carbon products","authors":"Hualong Yu \u0000 (,&nbsp;),&nbsp;Zhengrong Xu \u0000 (,&nbsp;),&nbsp;Yang Yang \u0000 (,&nbsp;),&nbsp;Aiguo Kong \u0000 (,&nbsp;),&nbsp;Zilin Zhao \u0000 (,&nbsp;),&nbsp;Yang Hou \u0000 (,&nbsp;),&nbsp;Rui Liu \u0000 (,&nbsp;)","doi":"10.1007/s40843-026-4113-3","DOIUrl":"10.1007/s40843-026-4113-3","url":null,"abstract":"<div><p>Constructing abundant grain boundary defects is a promising strategy for developing high-efficiency catalysts. However, achieving dense grain boundary defects in CuO and Cu at the nanoscale remains challenging. Inspired by Turing patterns in nature, a Turing-type CuO catalyst (TGB-CuO) with abundant grain boundaries at ∼10 nm nanoscale was prepared by annealing a dodecyl sulfate-intercalated basic copper carbonate. The balanced diffusion-reaction dynamics during pyrolysis drove the spontaneous formation of Turing-type grain boundary architectures in TGB-CuO. The resulting TGB-CuO electrode exhibited outstanding performance in electrochemical CO₂ reduction (ECO₂RR), delivering a Faradaic efficiency of 80.15% toward multi-carbon (C₂₊) products and maintaining over 50% ethylene selectivity at 300 mA cm⁻² for 30 h of continuous operation. Activity investigations indicated that the metallic Cu retaining Turing-type grain boundary features (TGB-Cu) formed during electroreduction was responsible for the enhanced ECO₂RR performance. The Cu(100)/(100), Cu(100)/(111), and Cu(111)/(111) grain boundaries promoted CO₂ activation and *CO adsorption, while lowering the free energy barriers for the rate-determining *CO₂⁻ → *COOH step and C–C coupling step. This bioinspired reaction-diffusion strategy offers a new paradigm for creating high-density grain boundary defects, offering a general route toward efficient catalyst design.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":773,"journal":{"name":"Science China Materials","volume":"69 10","pages":"6339 - 6349"},"PeriodicalIF":7.7,"publicationDate":"2026-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149098171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In-depth research on atomic-level issues in the field of single-atom catalyst synthesis","authors":"Yujia Gao \u0000 (,&nbsp;),&nbsp;Naiwen Liu \u0000 (,&nbsp;),&nbsp;Wenxia Xu \u0000 (,&nbsp;),&nbsp;Jianping Lai \u0000 (,&nbsp;),&nbsp;Lei Wang \u0000 (,&nbsp;)","doi":"10.1007/s40843-026-4101-5","DOIUrl":"10.1007/s40843-026-4101-5","url":null,"abstract":"<div><p>Single-atom catalysts, as a frontier in catalytic science, exhibit broad prospects in energy conversion and high-end chemical synthesis due to their theoretically achievable 100% atom utilization efficiency, highly tunable electronic structures, and coordination microenvironments. However, this system still faces several key challenges at the atomic scale, such as disordered active site distribution, constrained electronic structure, easy agglomeration of metal atoms, difficulty in effectively increasing loading capacity, and insufficient precision in regulating the coordination environment, which severely restrict further optimization of their catalytic performance and practical application progress. This review systematically analyzes the intrinsic connections and coupling relationships among these challenges from a mechanistic perspective, pointing out that they collectively constitute a multi-level, interconnected systemic problem rather than being independent issues. Based on summarizing the latest regulation strategies such as support engineering, coordination regulation, spatial confinement, and dynamic synthesis, this article emphasizes the significant value of multi-strategy synergy in achieving performance breakthroughs. Looking forward, future research in this field should focus on developing <i>in-situ</i> characterization methods with high spatial and temporal resolution, exploring multi-site synergistic catalytic mechanisms, and promoting the construction of standardized databases and rational design platforms. Ultimately, these efforts are expected to enable large-scale technological advances in clean energy and green chemical processes.\u0000</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":773,"journal":{"name":"Science China Materials","volume":"69 9","pages":"5265 - 5282"},"PeriodicalIF":7.7,"publicationDate":"2026-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148961985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Remarkable roles of electron-rich Mo and electron-deficient Ni active pairs in MoN/Ni heterostructures in promoting efficient urea oxidation reaction","authors":"Chen-Jin Huang \u0000 (,&nbsp;),&nbsp;Ruo-Zheng Xiong \u0000 (,&nbsp;),&nbsp;Hui-Min Xu \u0000 (,&nbsp;),&nbsp;Hong-Rui Zhu \u0000 (,&nbsp;),&nbsp;Hong-Cheng Zhang \u0000 (,&nbsp;),&nbsp;Chen-Yu Song \u0000 (,&nbsp;),&nbsp;Vyacheslav Yu Fominski \u0000 (,&nbsp;),&nbsp;Gao-Ren Li \u0000 (,&nbsp;)","doi":"10.1007/s40843-025-4162-0","DOIUrl":"10.1007/s40843-025-4162-0","url":null,"abstract":"<div><p>The application of urea oxidation reaction (UOR) can assist in hydrogen production through water electrolysis and reduce energy consumption. Ni-based catalysts have received widespread attention in the field of water electrolysis due to their low cost and high catalytic activity. However, the unavoidable Ni self-oxidation reaction (NSOR) of Ni-based catalysts will lead to unnecessary energy waste and strong adsorption of CO₂ during UOR, which will affect the activity of the active sites. Herein, we designed the MoN/Ni heterostructure to optimize the electronic structure of Ni sites in Ni-based catalysts to avoid NSOR. The X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS) verified that the MoN/Ni heterostructure could induce the generation of electron-rich Mo sites and electron-deficient Ni sites active pairs in the catalyst. <i>In-situ</i> spectroscopic characterizations, electrochemical tests, and theoretical calculations all demonstrated that the electron-rich Mo sites promoted urea adsorption, and the electron-deficient Ni sites prevented the occurrence of NSOR, thereby promoting the activation of urea, rapid conversion of intermediate species, and desorption of CO₂ (the product of UOR). The synergistic effect of electron-rich Mo and electron-deficient Ni active pairs endows the catalyst with high catalytic activity for UOR, and can achieve a current density of 100 mA cm⁻² at only about 1.39 V vs. RHE, which is superior to many catalysts with NiOOH as the active site. This work has developed a novel high-performance catalyst with electron-rich and electron-deficient active pairs, which can be used for efficient urea oxidation.\u0000</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":773,"journal":{"name":"Science China Materials","volume":"69 9","pages":"5529 - 5539"},"PeriodicalIF":7.7,"publicationDate":"2026-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148961983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of order-disorder transitions on the irradiation behavior of Gd2Zr2O7 and Gd2(Ti0.2Zr0.2Hf0.2Nb0.2Ce0.2)2O7 ceramics","authors":"Neng Zhang \u0000 (,&nbsp;),&nbsp;Weichao Bao \u0000 (,&nbsp;),&nbsp;Lin Zhou \u0000 (,&nbsp;),&nbsp;Fei Li \u0000 (,&nbsp;),&nbsp;Shi-Kuan Sun \u0000 (,&nbsp;),&nbsp;Xiao-Ting Xin \u0000 (,&nbsp;),&nbsp;Hong Su \u0000 (,&nbsp;),&nbsp;Yi-Hang Lv \u0000 (,&nbsp;),&nbsp;Xiao-Fei Wang \u0000 (,&nbsp;),&nbsp;Bo-Wen Yang \u0000 (,&nbsp;),&nbsp;Xin-Gang Wang \u0000 (,&nbsp;),&nbsp;Ji-Xuan Liu \u0000 (,&nbsp;),&nbsp;Ji Zou \u0000 (,&nbsp;),&nbsp;Fangfang Xu \u0000 (,&nbsp;)","doi":"10.1007/s40843-025-4095-4","DOIUrl":"10.1007/s40843-025-4095-4","url":null,"abstract":"<div><p>A₂B₂O₇ pyrochloresare considered potential candidates for next-generation high-level wastes (HLWs) immobilization. Energetic radiation particles from the waste can induce defects in A₂B₂O₇ and trigger a unique pyrochlore-to-fluorite phase transition, which involves cation and anion order-disorder transitions. Here, effects of order-disorder transition on the irradiation behavior of Gd₂Zr₂O₇ (GZO) and high-entropy Gd₂(Ti_0.2Zr_0.2Hf_0.2Nb_0.2Ce_0.2)₂O₇ (HE-GMO) pyrochlores have been investigated under 540 keV helium (He) ion irradiation with a total fluence of 1×10¹⁷ ions/cm² at room temperature and subsequent 300 and 600 °C annealing. Experiments confirmed that the pyrochlore-to-fluorite phase transition occurred under irradiation, involving order-disorder processes of both oxygen vacancies and metal ions via forming cation anti-site defects (CAD), which helps the materials maintain high crystallinity during irradiation. However, the migration of intrinsic oxygen vacancies promoted the growth of helium bubbles (&gt;1 nm), a phenomenon rarely observed in carbides and most other ceramics irradiated at room temperature. Helium bubbles agglomerate to form strings in GZO while they are evenly dispersed in HE-GMO due to the retarded diffusion effect of high-entropy. After annealing, both GZO and HE-GMO partially recovered their pyrochlore structure, except in the region of the helium concentration peak. GZO developed microcracks due to enhanced helium migration and aggregation. In contrast, HE-GMO maintained the size and dispersion of helium bubbles after annealing, demonstrating excellent helium bubble stability. However, a significant stress mismatch at the interface between the peak damage zone and the adjacent area led to the formation of catastrophic macroscopic cracks.\u0000</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":773,"journal":{"name":"Science China Materials","volume":"69 10","pages":"6142 - 6152"},"PeriodicalIF":7.7,"publicationDate":"2026-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149098130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}