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Facile and adjustable production of self–standing oxygen–doped graphene membranes for optimized oxygen evolution electrocatalysis

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Nano Materials science 2025年第2期7卷 231-239页

作者： Chen, Liang Yang, Lanyun Hu, Liying Jin, Minghao Xu, Chenxi He, Binhong Wang, Wei Liu, Ying Li, Gangyong Hou, Zhaohui Key Laboratory of Hunan Province for Advanced Carbon‒based Functional Materials School of Chemistry and Chemical Engineering Hunan Institute of Science and Technology Hunan Yueyang414006 China College of Materials Science and Engineering Central South University of Forestry and Technology Hunan Changsha410004 China

Owing to abundant resource and affordable price, metal–free carbon has been extensively studied in the field of oxygen reduction reaction, while the related studies on oxygen evolution reaction (OER) are quite few. In this work, a facile and scalable knife coating coupled with annealing strategy is proposed to produce self–standing oxygen–doped graphene membranes (marked as O–GM–T, T represents the annealing temperature). Through systematic characterization and analysis, it is discovered the annealing treatment not only decreases the amount of oxygenic groups, but allows for controlled regulation of the oxygen configurations, leaving only C–OH/C–O–C and C[dbnd]O. Meanwhile, theoretical calculations indicate that the OER activity trend of different oxygen configurations is as follows: –COOH > C[dbnd]O ≈ C–OH > C–O–C. Despite the removal of highly active –COOH group through annealing treatment, the resulting O–GM–800 sample maintains good mechanical property and achieves a favorable balance on conductivity, hydrophilicity and catalytic sites. Consequently, it displays significantly improved OER performance compared to the counterparts, making it highly promising for applications in overall water splitting devices. Apparently, our work provides guidance for the rational design and controllable fabrication of self–standing carbon–based catalysts for energy–related reactions. © 2025 Chongqing University

关键词： Coatings

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Abnormal dielectric behavior of glaserite-type Ba_(3−x)Sr_(x)MgSi_(2)O_(8)solid solution

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Journal of advanced Ceramics 2025年第2期14卷 77-86页

作者： Jiaqing Yang Peng Lei Xiaoqiang Song Changzhi Yin Meng Zhang Weicheng Lei Yiyang Cai Mingfei Cheng Yaodong Liu Zihang Chen Yaqing Hu Wenzhong Lu Wen Lei School of Optical and Electronic Information Key Lab of Functional Materials for Electronic Information(B)of MOEHuazhong University of Science and TechnologyWuhan 430074China Wenzhou Key Laboratory of Microwave Communication Materials and Devices Wenzhou Advanced Manufacturing Institute of HUSTWenzhou 325035China

The temperature coefficient of the resonant frequency(τ_(f))of low-permittivity(ε_(r))microwave dielectric ceramics is required to be near 0 ppm/℃for practical ***,owing to the polarization mechanism,τ_(f)of low-ε_(r)microwave dielectric ceramics is generally ***,a novel microwave dielectric ceramic,Ba_(3−x)Sr_(x)MgSi_(2)O_(8),with an abnormal positiveτ_(f)at the applied temperature is *** this study,Sr^(2+)with a relatively small ionic radius was introduced to replace Ba^(2+),and a single-phase solid solution was formed(x>0.5).Ba_(3−x)Sr_(x)MgSi_(2)O_(8)ceramics were discussed in glaserite-type topology with space groups of P_(3)^(-)for x≤0.5,relatively high symmetry P_(3)^(-)m1 for 0.5functional theory simulation calculations revealed that the preferential occupation of Sr^(2+)ions could decrease the intrinsic formation energy and improve the microwave dielectric properties by mitigating the ionic size mismatch within the crystal *** present research offers a strategy for discovering novel microwave dielectric ceramics with abnormalτ_(f)values,which could serve as τ_(f)regulators in practical applications because of their low cost and excellent microwave dielectric properties.

关键词： microwave dielectric ceramics abnormal dielectric behavior ion size mismatch [SiO4]tetrahedra tilting phase transition density functional theory(DFT)

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Prediction of New functional Fluorooxoborates with Expected Anionic Framework:A Case of CaB_(3)O_(5)F

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Chinese Physics Letters 2025年第3期42卷 85-92页

作者： Ke-Wang Zhang Wen-Qi Jin Ke Li Abudukadi Tudi Lin-Lin Liu Cong-Wei Xie Yu Xie Research Center for Crystal Materials CAS Key Laboratory of Functional Materials and Devices for Special Environmental ConditionsXinjiang Key Laboratory of Functional Crystal MaterialsXinjiang Technical Institute of Physics&ChemistryCASUrumqi 830011China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Materials Simulation Methods&Software of Ministry of Education International Center of Future ScienceKey Laboratory of Physics and Technology for Advanced Batteries(Ministry of Education)College of PhysicsJilin UniversityChangchun 130012China

The prediction of new fluorooxoborates as ultraviolet(UV)/deep ultraviolet(DUV)opto-electronic functional materials from a largely unexplored chemical space is a challenging *** has been suggested that the anionic frameworks formed by B–O and B–O–F units significantly determine the physical properties of ***,the rational design of anionic frameworks could facilitate the materials discovery ***,we propose that a candidate anionic framework can be efficiently derived from an existing one by slightly altering its oxygen *** this idea,we hypothesized the existence of a 1D[B_(3)O_(5)F]_(∞)chain from the wellknown 2D[B_(6)O_(9)F_(2_)]_(∞)***,seven CaB_(3)O_(5)F structures with the expected anionic framework were successfully ***-principles calculations show that all these structures have potential in the UV/DUV birefringent or nonlinear optical(NLO)material field,indicating that the 1D[B_(3)O_(5)F]_(∞)chain is indeed a promising anionic framework for achieving UV/DUV birefringent and NLO performance.

关键词： process borate anionic

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Dual-functional additive of cesium ion for achieving ultrahigh efficiency of persistent phosphorescence in existing polymer-based materials

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science China Chemistry 2025年第2期68卷 754-762页

作者： Yao Liu Jinzheng Chen Yiling Miao Kaimin Zhang Faxu Lin Huahua Huang Lina Zhang Zhan Yang Yi Zhang Zhenguo Chi Zhiyong Yang Key Laboratory for Polymeric Composite&Functional Materials of Ministry of Education Guangdong Engineering Technology Research Center for High-performance Organic and Polymer Photoelectric Functional FilmsGuangdong Basic Research Center of Excellence(GBRCE)for Functional Molecular EngineeringSchool of ChemistrySun Yat-sen UniversityGuangzhou 510275China School of Materials Science and Engineering Sun Yat-sen UniversityGuangzhou 510275China College of Materials Science and Engineering Hebei University of EngineeringHandan 056038China School of Environmental and Chemical Engineering Wuyi UniversityJiangmen 529020China

Despite great achievements obtained for polymer-based room-temperature phosphorescence(RTP)materials,the limited efficiencies of persistent RTP still hinder their ***,a simple and universal strategy of using the dual-functional additive of Cs+was presented,which could simultaneously enhance the efficiency(Φp)and maintain the long lifetime(τp)of RTP in existing polymer-based systems with various phosphors and *** them,the commercial emitter(TpB)-doped polyvinyl alcohol(PVA)/Cs_(2)CO_(3) system possessed an extremely high Φp up to 75.5% and still maintained a longτp of 2.13 s,by introducing the heavy-atom effect and an extra network of ionic bonding through the Cs+***,the temperature resistance of RTP in TpB@PVA/Cs+film could also be improved to 85℃.More satisfactorily,the efficiency of Förster resonance energy transfer(FRET)from RTP to near-infrared(NIR)was also remarkably enhanced in the multi-component *** work provides a simple and universal strategy for developing polymer systems with high RTP performance.

关键词： persistent phosphorescence cesium carbonate efficiency heavy-atom effect ionic interaction

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Ultrasonic sprayed hollow ceramic/carbon microspheres function as thermal insulation, ablative resistance, and electromagnetic shielding materials

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Ceramics International 2025年第13期51卷 18029-18037页

作者： Qin, Chuhui Zhong, Hangyu Hu, Hongli Kang, Zhonglei Zhang, Bo-xing South China Advanced Institute for Soft Matter Science and Technology School of Emergent Soft Matter South China University of Technology Guangzhou510640 China Guangdong Provincial Key Laboratory of Functional and Intelligent Hybrid Materials and Devices South China University of Technology Guangzhou510640 China

Hollow ceramic/carbon microspheres (HCCMs) have widespread applications for thermal insulation and ablative resistance materials in aerospace areas, attributed to their multiple advantages such as low density, low thermal conductivity, oxidation and high-temperature resistance. In this work, we fabricated HCCMs with diameters around 18–242 μm by the ultrasonic spray method, using mixed solutions of poly(acrylonitrile) (PAN), polyvinyl pyrrolidone (PVP), and preceramic polymers as starting materials. After optimizing the morphology of HCCMs, we introduced them as fillers into phenolic resin (PR). By adjusting the ratio between HCCMs and PR, the optimal properties were obtained at a loading content of 30 wt% of HCCMs. The density of as-obtained PR composite was 0.70 g/cm3, the thermal conductivity was 0.27 W/(m·K), and the maximum electromagnetic shielding effectiveness was 76.30 dB at the frequency of 8–12 GHz. This work develops a powerful approach to fabricating HCCMs, and demonstrates their typical application as fillers in PR to improve thermal insulation, electromagnetic shielding, and ablative resistance performance. © 2025 Elsevier Ltd and Techna Group S.r.l.

关键词： Microspheres

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Carbon Nanofiber/Polyaniline composite Aerogel with Excellent Electromagnetic Interference Shielding,Low Thermal Conductivity,and Extremely Low Heat Release

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Nano-Micro Letters 2025年第4期17卷 77-95页

作者： Mingyi Chen Jian Zhu Kai Zhang Hongkang Zhou Yufei Gao Jie Fan Rouxi Chen Hsing-Lin Wang School of Textile Science and Engineering Tiangong UniversityTianjin 300387People’s Republic of China Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055People’s Republic of China School of Innovation and Entrepreneurship Southern University of Science and TechnologyShenzhen 518055People’s Republic of China Guangdong Provincial Key Laboratory of Energy Materials for Electric Power Southern University of Science and TechnologyShenzhen 518055People’s Republic of China Ministry of Education Key Laboratory of Advanced Textile Composite Materials Tiangong UniversityTianjin 300387People’s Republic of China

The rapid development of communication technology and high-frequency electronic devices has created a need for more advanced electromagnetic interference(EMI)shielding *** response to this demand,a study has been conducted to develop multifunctional carbon nanofibers(CNFs)/polyaniline(PANI)aerogels with excellent electromagnetic interference shielding,flame retardancy,and thermal insulation *** process involved freeze-drying of electrospun CNFs and PANI nanoparticles followed by in situ growth PANI to coat the CNFs,creating the core-shell structured CNFs/PANI composite fiber and its hybrid aerogels(CP-3@PANI).The interaction between PANI and aniline(ANI)provides attachment sites,allowing additional ANI adsorption into the aerogel for in situ *** results in PANI uniformly covering the surface of the CNFs,creating a core-shell composite fiber with a flexible CNF core and PANI *** process enhances the utilization rate of the ANI monomer and increases the PANI content loaded onto the ***,effective connections are established between the CNFs,forming a stable,conductive three-dimensional network *** prepared CP-3@PANI aerogels exhibit excellent EMI shielding efficiency(SE)of 85.4 dB and specific EMI SE(SE d^(-1))of 791.2 dB cm^(3)g^(-1)in the *** to the synergistic flame-retardant effect of CNFs,PANI,and the dopant(phytic acid),the CP-3@PANI aerogels demonstrate outstanding flame-retardant and thermal insulation properties,with a peak heat release rate(PHRR)as low as 7.8 W g^(-1)and a total heat release of only 0.58 kJ g^(-1).This study provides an effective strategy for preparing multifunctional integrated EMI shielding materials.

关键词： CNFs/PANI hybrid aerogels EMI shielding Flame retardancy Thermal insulation

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PtPdAg nanotrees with low Pt content for high CO tolerance within formic acid and methanol electrooxidation

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Rare Metals 2025年第1期44卷 300-310页

作者： Yu-Fei Wang Shou-Lin Zhang Yu-Xin Deng Shi-Han Luan Cai-Kang Wang Lin-Fei Ding Xian Jiang Dong-Mei Sun Ya-Wen Tang Jiangsu Key Laboratory of New Power Batteries Jiangsu Collaborative Innovation Centre of Biomedical Functional MaterialsSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China School of New Energy Nanjing University of Science and TechnologyJiangyin 214443China Advanced Analysis and Testing Center Nanjing Forestry UniversityNanjing 210037China

To efficiently diminish the Pt consumption while concurrently enhancing the anodic reaction kinetics,a straightforward synthesis for PtPdAg nanotrees(NTs)with exceedingly low Pt content is presented,utilizing the galvanic replacement reaction between the initially prepared PdAg NTs and Pt *** to the multilevel porous tree-like structure and the incorporation of low amounts of Pt,the electrocatalytic activity and stability of PtPdAg NTs are markedly enhanced,achieving 1.65 and 1.69 A·mg^(-1)Pt+Pd for the anodic reactions of formic acid oxidation(FAOR)and methanol oxidation(MOR)within DLFCs,surpassing the performance of PdAg NTs,as well as that of commercial Pt and Pd *** functional theory(DFT)calculations reveal that the addition of low amounts of Pt leads to an increase in the d-band center of PtPdAg NTs and lower the COads adsorption energy to-1.23 eV,enhancing the anti-CO toxicity properties *** approach offers an effective means for designing low Pt catalysts as exceptional anodic electrocatalysts for direct liquid fuel cells.

关键词： PtPdAg nanotrees Low Pt Bifunctional electrocatalysts Methanol oxidation reaction Formic acid oxidation

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Design principles of fluoroether solvents for lithium metal battery electrolytes unveiled by extensive molecular simulation and machine learning

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Journal of Energy Chemistry 2025年第3期102卷 52-62页

作者： Xueying Yuan Xiupeng Chen Yuanxin Zhou Zhiao Yu Xian Kong South China Advanced Institute for Soft Matter Science and Technology School of Emergent Soft MatterSouth China University of TechnologyGuangzhou 510640GuangdongChina Department of Chemical Engineering Stanford UniversityStanfordCA 94305USA Guangdong Provincial Key Laboratory of Functional and Intelligent Hybrid Materials and Devices South China University of TechnologyGuangzhou 510640GuangdongChina

Electrolyte engineering with fluoroethers as solvents offers promising potential for high-performance lithium metal *** recent progresses achieved in designing and synthesizing novel fluoroether solvents,a systematic understanding of how fluorination patterns impact electrolyte performance is still *** investigate the effects of fluorination patterns on properties of electrolytes using fluorinated 1,2-diethoxyethane(FDEE)as single *** employing quantum calculations,molecular dynamics simulations,and interpretable machine learning,we establish significant correlations between fluorination patterns and electrolyte *** fluorination levels enhance FDEE stability but decrease *** symmetry of fluorination sites is critical for stability and viscosity,while exerting minimal influence on ionic *** with highly symmetric fluorination sites exhibit favorable viscosity,stability,and overall electrolyte *** primarily depends on lithium-anion dissociation or *** findings provide design principles for rational fluoroether electrolyte design,emphasizing the trade-offs between stability,viscosity,and *** work underscores the significance of considering fluorination patterns and molecular symmetry in the development of fluoroether-based electrolytes for advanced lithium batteries.

关键词： Electrolyte engineering Fluoroether solvent Molecular simulation Machine learning

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Controllable synthesis and structure-activity relationship of Ni doping in SmCrO3 for improved magnetic and dielectric properties

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International Journal of Minerals, Metallurgy and Materials 2025年 1-11页

作者： Huang, Wenjie Li, Rui Zhang, Ruoxuan Cui, Yimin Wang, Rongming Beijing Key Laboratory for Magneto–Photoelectrical Composite and Interface Science State Key Laboratory for Advanced Metals and Materials School of Mathematics and Physics University of Science and Technology Beijing Beijing100083 China School of Physics Beihang University Beijing100191 China

Doping small amounts at the A-site or B-site of SmCrO3 ceramics is a promising approach for modifying their microstructure, as well as their magnetic and dielectric properties. In this study, polycrystalline ceramics of Sm1−xNixCrO3 (x = 0, 0.05, and 0.20) and SmCr1−yNiyO3 (y = 0.05 and 0.20) were synthesized via a conventional solid-state reaction. X-ray diffraction validated that all the doped ceramics maintained an orthorhombic crystalline structure consistent with the Pbnm space group. Furthermore, X-ray photoelectron spectroscopy demonstrated the presence of Ni2+ ions in the doped specimens. Notably, doping resulted in significant enhancement of low-temperature magnetic properties, particularly in samples doped at the A-site, such as Sm0.80Ni0.20CrO3. Compared with the pristine sample, the maximum magnetization of Sm0.80Ni0.20CrO3 increased by approximately 60.9% and 93.5% in the zero-field cooling and field-cooling modes, respectively, in an external magnetic field of 100 Oe. Furthermore, the dielectric constants of the Ni-doped ceramics initially exceeded that of the pristine sample as the temperature increased. At equivalent doping ratios, A-site doping demonstrated superior performance over B-site doping, including higher magnetization, lower dielectric loss, and enhanced electrical quality factors. © University of science and technology Beijing 2025.

关键词： Dielectric properties of solids

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Rapid prediction of effective absorption bandwidth in PEEK/CF additive manufacturing metastructure via interpretable machine learning

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Journal of Materials science and technology 2025年 239卷 307-319页

作者： Gao, Shuailong Dong, Huaiyu Zhang, Yuhui Sun, Yingjian Yu, Chen Wang, Zhichen Zhang, Haofeng Huang, Yixing Li, Ying Beijing Key Laboratory of Lightweight Multi-functional Composite Materials and Structures Institute of Advanced Structure Technology Beijing Institute of Technology Beijing100081 China

The development of machine learning has provided a new perspective for the design of electromagnetic metastructures, particularly in the rapid design of key performance metrics such as effective absorption bandwidth. Traditional methods, grounded in electromagnetic theory and empirical approaches, often lacked sufficient flexibility and adaptability. In this work, three types of machine learning models were developed to establish the relationship between effective absorption bandwidth and structural parameters. The results indicated that the random forest model achieved the most accurate and efficient design for this task. Then, the additive manufacturing optimal metastructure obtained using this approach outperformed existing designs in terms of both effective absorption bandwidth and reflectivity, while also exhibiting superior radar stealth performance and mechanical load-bearing capacity. Furthermore, through interpretable machine learning and data analysis, the intrinsic mechanisms underlying the relationship between effective absorption bandwidth and structural parameters were revealed. Overall, this work introduced a novel approach to metastructure design and enhanced the understanding of the relationship between structural parameters and electromagnetic properties, providing a key foundation for future design. © 2025

关键词： Bearings (machine parts)

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