Hao-Yang Li, Hyunseung Kim, Jeong Woo Shin, Jiyoon Shin, Pei-Chen Su
Solid oxide fuel cells (SOFCs) offer high efficiency and fuel flexibility for next-generation energy conversion, yet direct utilization of methane and ammonia remains hindered by anode degradation from carbon coking, nitridation, and sluggish reaction kinetics in conventional Ni-based cermets. This review systematically examines surface modification strategies, specifically infiltration, exsolution, and atomic layer deposition (ALD), to enhance anode stability and performance. Emphasis is placed on ALD as an emerging, transformative technique, prized for its atomic-level precision, superior conformality over complex porous architectures, and ability to achieve low catalyst loading with controllable uniformity—challenges that conventional methods often struggle to address. Comparative literature analysis confirms that ALD surface modifications enhance anode performance and stability more effectively than infiltration (nonuniform) or exsolution (limited tunability) by enabling precise engineering of triple-phase boundaries and protective interfaces. Looking forward, scalable ALD processes, multifunctional multilayers, and hybrid integrations are identified as key avenues for enabling the commercialization of durable, direct-fueled SOFCs.
{"title":"Surface modification strategies for direct methane and direct ammonia solid oxide fuel cell anodes: current approaches and future directions","authors":"Hao-Yang Li, Hyunseung Kim, Jeong Woo Shin, Jiyoon Shin, Pei-Chen Su","doi":"10.1039/d5ta03551a","DOIUrl":"https://doi.org/10.1039/d5ta03551a","url":null,"abstract":"Solid oxide fuel cells (SOFCs) offer high efficiency and fuel flexibility for next-generation energy conversion, yet direct utilization of methane and ammonia remains hindered by anode degradation from carbon coking, nitridation, and sluggish reaction kinetics in conventional Ni-based cermets. This review systematically examines surface modification strategies, specifically infiltration, exsolution, and atomic layer deposition (ALD), to enhance anode stability and performance. Emphasis is placed on ALD as an emerging, transformative technique, prized for its atomic-level precision, superior conformality over complex porous architectures, and ability to achieve low catalyst loading with controllable uniformity—challenges that conventional methods often struggle to address. Comparative literature analysis confirms that ALD surface modifications enhance anode performance and stability more effectively than infiltration (nonuniform) or exsolution (limited tunability) by enabling precise engineering of triple-phase boundaries and protective interfaces. Looking forward, scalable ALD processes, multifunctional multilayers, and hybrid integrations are identified as key avenues for enabling the commercialization of durable, direct-fueled SOFCs.","PeriodicalId":82,"journal":{"name":"Journal of Materials Chemistry A","volume":"9 1","pages":""},"PeriodicalIF":11.9,"publicationDate":"2026-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146116113","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}
Proton exchange membranes (PEMs) are critical to the performance of vanadium redox flow batteries (VRFBs). Still, conventional perfluorosulfonic acid membranes such as Nafion ® suffer from poor ion selectivity and limited long-term stability. In this study, we introduce PEMs prepared from four types of poly(arylene perfluorobenzenesulfonic acid)s, synthesized via polyhydroxyalkylations of biphenyl (BP) or p-terphenyl (TP) with pentafluorobenzaldehyde (BA) or perfluoroacetophenone (AP), and are named according to their monomer contents (e.g., sBPBA). The combination of the rigid and ether-free polymer backbones and the densely distributed highly acidic sulfonic acid groups led to high proton conductivity and improved ion selectivity. In addition, the -CF3 substitution in the PEMs derived from perfluoroacetophenone likely increased the free volume and enhanced chemical stability. These membranes displayed reduced area resistance and markedly lower vanadium ion permeability compared with Nafion ® 115. In VRFB single-cell tests, the membranes sBPBA, sTPBA, and sBPAP consistently delivered higher voltage and energy efficiencies than Nafion ® 115 across 40-160 mA cm⁻ 2 , with the former PEM achieving the highest energy efficiency at all current densities. Long-term cycling demonstrated outstanding stability for sBPAP (~99.5% CE, ~82% EE over 450 cycles), moderate stability for sTPAP (~98% CE over 250 cycles), and rapid performance degradation for sBPBA and sTPBA, prepared from pentafluorobenzaldehyde. This study demonstrates that CF3-containing poly(arylene perfluorophenyl) PEMs, which contain only a small fraction of the perfluoroalkyl (PFAS) content found in Nafion ® , are promising candidates for high-efficiency, durable VRFB operation. It also provides a clear molecular design framework for developing advanced membrane materials.
质子交换膜（PEMs）对钒氧化还原液流电池（VRFBs）的性能至关重要。然而，传统的全氟磺酸膜（如Nafion®）存在离子选择性差和长期稳定性有限的问题。在本研究中，我们介绍了四种类型的聚芳烯全氟苯磺酸（PEMs），通过联苯（BP）或对三苯（TP）与五氟苯甲醛（BA）或全氟苯酮（AP）的聚羟基烷基化合成，并根据其单体含量（如sBPBA）命名。刚性和无醚聚合物骨架与密集分布的强酸性磺酸基团的结合导致了高质子导电性和离子选择性的提高。此外，由全氟苯乙酮衍生的PEMs中的-CF3取代可能增加了自由体积并增强了化学稳定性。与Nafion®115相比，这些膜显示出降低的面积阻力和显著降低的钒离子渗透性。在VRFB单细胞测试中，隔膜sBPBA， sTPBA和sBPAP在40-160 mA cm - 2范围内始终比Nafion®115提供更高的电压和能量效率，前者的PEM在所有电流密度下都具有最高的能量效率。长期循环表明，sBPAP具有优异的稳定性（450次循环~99.5% CE, ~82% EE）， sTPAP具有中等稳定性（250次循环~98% CE），而由五氟苯甲醛制备的sBPBA和sTPBA的性能下降很快。该研究表明，含cf3的聚（芳烯全氟苯基）PEMs仅含有Nafion®中全氟烷基（PFAS）含量的一小部分，是高效、耐用VRFB操作的有希望的候选者。这也为开发先进的膜材料提供了清晰的分子设计框架。
{"title":"Proton exchange membranes with perfluorobenzenesulfonic acid groups for vanadium redox flow battery applications","authors":"Xiaoting Xue, Peiru Lv, Jingshuai Yang, Patric Jannasch","doi":"10.1039/d5ta08577b","DOIUrl":"https://doi.org/10.1039/d5ta08577b","url":null,"abstract":"Proton exchange membranes (PEMs) are critical to the performance of vanadium redox flow batteries (VRFBs). Still, conventional perfluorosulfonic acid membranes such as Nafion ® suffer from poor ion selectivity and limited long-term stability. In this study, we introduce PEMs prepared from four types of poly(arylene perfluorobenzenesulfonic acid)s, synthesized via polyhydroxyalkylations of biphenyl (BP) or p-terphenyl (TP) with pentafluorobenzaldehyde (BA) or perfluoroacetophenone (AP), and are named according to their monomer contents (e.g., sBPBA). The combination of the rigid and ether-free polymer backbones and the densely distributed highly acidic sulfonic acid groups led to high proton conductivity and improved ion selectivity. In addition, the -CF3 substitution in the PEMs derived from perfluoroacetophenone likely increased the free volume and enhanced chemical stability. These membranes displayed reduced area resistance and markedly lower vanadium ion permeability compared with Nafion ® 115. In VRFB single-cell tests, the membranes sBPBA, sTPBA, and sBPAP consistently delivered higher voltage and energy efficiencies than Nafion ® 115 across 40-160 mA cm⁻ 2 , with the former PEM achieving the highest energy efficiency at all current densities. Long-term cycling demonstrated outstanding stability for sBPAP (~99.5% CE, ~82% EE over 450 cycles), moderate stability for sTPAP (~98% CE over 250 cycles), and rapid performance degradation for sBPBA and sTPBA, prepared from pentafluorobenzaldehyde. This study demonstrates that CF3-containing poly(arylene perfluorophenyl) PEMs, which contain only a small fraction of the perfluoroalkyl (PFAS) content found in Nafion ® , are promising candidates for high-efficiency, durable VRFB operation. It also provides a clear molecular design framework for developing advanced membrane materials.","PeriodicalId":82,"journal":{"name":"Journal of Materials Chemistry A","volume":"39 1","pages":""},"PeriodicalIF":11.9,"publicationDate":"2026-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146116245","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}
Esther M. Curtis, Kehan Huang, Josie E. Auckett, Stephen J. Skinner, Ivana Radosavljević Evans
Correction for ‘On the transport properties of K2ZnV2O7’ by Esther M. Curtis et al., J. Mater. Chem. A, 2026, https://doi.org/10.1039/D5TA09854H.
更正Esther M. Curtis et al.， J. Mater对“关于K2ZnV2O7的输运性质”的更正。化学。A, 2026, https://doi.org/10.1039/D5TA09854H。
{"title":"Correction: On the transport properties of K2ZnV2O7","authors":"Esther M. Curtis, Kehan Huang, Josie E. Auckett, Stephen J. Skinner, Ivana Radosavljević Evans","doi":"10.1039/d6ta90041k","DOIUrl":"https://doi.org/10.1039/d6ta90041k","url":null,"abstract":"Correction for ‘On the transport properties of K<small><sub>2</sub></small>ZnV<small><sub>2</sub></small>O<small><sub>7</sub></small>’ by Esther M. Curtis <em>et al.</em>, <em>J. Mater. Chem. A</em>, 2026, https://doi.org/10.1039/D5TA09854H.","PeriodicalId":82,"journal":{"name":"Journal of Materials Chemistry A","volume":"4 1","pages":""},"PeriodicalIF":11.9,"publicationDate":"2026-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146116069","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}
Ying Sun, Fengyuan Ma, Xinke Wang, Zexi Li, Yanmei Yang, Ran Feng, Fei Zhang, Shenghong Yang, Ke Tang, Jian Liu
The afterglow properties of a single system are unable to achieve wide-range temperature-response conversion, constraining the development of tunable multi-emission afterglow. Here, we report a defect engineering strategy to achieve temperature-responsive conversion between blue and yellow afterglow properties in metal-free doped silica over a wide temperature range. Defects including intrinsic oxygen vacancies and extrinsic carbon impurities were co-introduced and stabilized within densified silica matrices. The carbon impurities activated partial oxygen defects and converted them from non-radiative centers into emissive centers, thus enhancing the yellow afterglow of oxygen vacancies that was typically suppressed. Dexter electron transfer for capturing released electrons plays a pivotal role in yellow afterglow. The doped silica exhibited a long afterglow duration exceeding 19 s at r.t., with a maximum lifetime of 3.54 s and a quantum yield of 16.68%. The broad-band afterglow spectra feature multi-emission profiles and distinct temperature-dependent afterglow dynamics. Silica densification provided rigid structural confinement, establishing physical barriers that shielded the defects from common passivation factors, thus ensuring robust photoluminescence properties. By leveraging the unique and robust temperature-responsive photoluminescence characteristics, we successfully demonstrated the doped silica for spatiotemporal-temperature anti-counterfeiting applications. Our findings offer valuable insights and a universal strategy for the rational design of defect-related afterglow materials and their tunable afterglow emission.
{"title":"Defect-engineered silica with temperature-responsive conversion of yellow and blue afterglow","authors":"Ying Sun, Fengyuan Ma, Xinke Wang, Zexi Li, Yanmei Yang, Ran Feng, Fei Zhang, Shenghong Yang, Ke Tang, Jian Liu","doi":"10.1039/d5ta07530k","DOIUrl":"https://doi.org/10.1039/d5ta07530k","url":null,"abstract":"The afterglow properties of a single system are unable to achieve wide-range temperature-response conversion, constraining the development of tunable multi-emission afterglow. Here, we report a defect engineering strategy to achieve temperature-responsive conversion between blue and yellow afterglow properties in metal-free doped silica over a wide temperature range. Defects including intrinsic oxygen vacancies and extrinsic carbon impurities were co-introduced and stabilized within densified silica matrices. The carbon impurities activated partial oxygen defects and converted them from non-radiative centers into emissive centers, thus enhancing the yellow afterglow of oxygen vacancies that was typically suppressed. Dexter electron transfer for capturing released electrons plays a pivotal role in yellow afterglow. The doped silica exhibited a long afterglow duration exceeding 19 s at r.t., with a maximum lifetime of 3.54 s and a quantum yield of 16.68%. The broad-band afterglow spectra feature multi-emission profiles and distinct temperature-dependent afterglow dynamics. Silica densification provided rigid structural confinement, establishing physical barriers that shielded the defects from common passivation factors, thus ensuring robust photoluminescence properties. By leveraging the unique and robust temperature-responsive photoluminescence characteristics, we successfully demonstrated the doped silica for spatiotemporal-temperature anti-counterfeiting applications. Our findings offer valuable insights and a universal strategy for the rational design of defect-related afterglow materials and their tunable afterglow emission.","PeriodicalId":82,"journal":{"name":"Journal of Materials Chemistry A","volume":"34 1","pages":""},"PeriodicalIF":11.9,"publicationDate":"2026-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146115970","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}
Duhaul Biqal Kautsar, Phong Hoai Le, Kosuke Kondo, Kiet Le Anh Cao, Eka Lutfi Septiani, Tomoyuki Hirano, Takashi Ogi
Correction for “Multiporous structure formation in three-way catalyst particles for enhanced catalytic performance” by Duhaul Biqal Kautsar et al., J. Mater. Chem. A, 2026, 14, 1110–1122, https://doi.org/10.1039/D5TA04974A.
In-depth investigation of the existence states of water in porous photothermal conversion material and effective reduction of the evaporation enthalpy are of great significance for constructing high-performance interfacial solar evaporation devices. In this study, photothermal conversion materials with different porous sizes were constructed using melamine foam (MF) as the substrate, low-cost quasi-metallic Co 2 C nanoparticles as the light absorber, and polyvinyl alcohol (PVA) as the binder. The hydrophilic PVA-Co 2 C formed an interconnected and open porous network within the MF framework. Low-field nuclear magnetic resonance, dark evaporation, and differential scanning calorimetry analyses indicated that the incorporation of PVA-Co 2 C enhanced the interaction between water molecules and the porous framework, facilitating the transformation of free bulk water 2 into surface bound water with weaker hydrogen bonding, thereby effectively reducing the evaporation enthalpy. Furthermore, the porous size and thickness of MF/PVA-Co 2 C significantly influenced water transport and distribution. At appropriate porous sizes and thicknesses, water could not completely fill the interconnected pores but instead formed a thin water layer, which enabled continuous water supply and efficient evaporation through confined capillary transport. This not only exposes a larger evaporation area and increases vapor escape channels but also ensures a balance between water-supply and evaporation. These synergistic effects significantly enhance water evaporation performance. Under 1.0 kW•m -2 light irradiation, the water evaporation rate reaches 3.1 kg•m -2 •h -1 . During continuous operation for 6 hours under partly cloudy weather with an average solar intensity of 577.2 W•m -2 , the cumulative water production remains as high as 8.4 kg•m -2 . This work presents a valuable guidance for the preparation of photothermal conversion materials using porous sponges as substrate, offering an effective solution to address freshwater scarcity.
{"title":"The porous size effect on water state and transport probed by 1 H LF-NMR relaxation: A case study of MF/PVA-Co 2 C photothermal conversion materials","authors":"Ting Wang, Shilong Yu, Xuepeng Yin, Tingting Zhao, Zhengyi Yang, Hao Niu, Fenglong Wang, Shanmin Gao","doi":"10.1039/d5ta09861k","DOIUrl":"https://doi.org/10.1039/d5ta09861k","url":null,"abstract":"In-depth investigation of the existence states of water in porous photothermal conversion material and effective reduction of the evaporation enthalpy are of great significance for constructing high-performance interfacial solar evaporation devices. In this study, photothermal conversion materials with different porous sizes were constructed using melamine foam (MF) as the substrate, low-cost quasi-metallic Co 2 C nanoparticles as the light absorber, and polyvinyl alcohol (PVA) as the binder. The hydrophilic PVA-Co 2 C formed an interconnected and open porous network within the MF framework. Low-field nuclear magnetic resonance, dark evaporation, and differential scanning calorimetry analyses indicated that the incorporation of PVA-Co 2 C enhanced the interaction between water molecules and the porous framework, facilitating the transformation of free bulk water 2 into surface bound water with weaker hydrogen bonding, thereby effectively reducing the evaporation enthalpy. Furthermore, the porous size and thickness of MF/PVA-Co 2 C significantly influenced water transport and distribution. At appropriate porous sizes and thicknesses, water could not completely fill the interconnected pores but instead formed a thin water layer, which enabled continuous water supply and efficient evaporation through confined capillary transport. This not only exposes a larger evaporation area and increases vapor escape channels but also ensures a balance between water-supply and evaporation. These synergistic effects significantly enhance water evaporation performance. Under 1.0 kW•m -2 light irradiation, the water evaporation rate reaches 3.1 kg•m -2 •h -1 . During continuous operation for 6 hours under partly cloudy weather with an average solar intensity of 577.2 W•m -2 , the cumulative water production remains as high as 8.4 kg•m -2 . This work presents a valuable guidance for the preparation of photothermal conversion materials using porous sponges as substrate, offering an effective solution to address freshwater scarcity.","PeriodicalId":82,"journal":{"name":"Journal of Materials Chemistry A","volume":"89 1","pages":""},"PeriodicalIF":11.9,"publicationDate":"2026-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146122399","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}
Fancang Meng, Huan Wu, Boyu Jia, Kexiang Li, Zhihua Wang, He Zhu, Chao Chen, Qingmin Ji
The development of Fe-N-C electrocatalysts for the oxygen reduction reaction (ORR) is crucial for sustainable energy technologies, yet achieving a high density of atomically dispersed Fe-Nx sites remains a challenge. Herein, we proposed a novel spatial confinement strategy based on the molecular-level infiltration of iron-coordinated, water-soluble fullerene (Fe/wsC60) into self-assembled fullerene microbelts (FMB). The -NH2/-OH functionalized C60s act as molecular metal chelator and nitrogen source, while the flexible FMB framework facilitates their effective permeation. This nanoscale confinement effectively mitigates Fe aggregation during pyrolysis, yielding a catalyst with abundant atomically dispersed curved Fe-N4 sites alongside fine Fe3C nanoparticles. The resultant (Fe/N@FMB) catalyst demonstrates an exceptional ORR activity and stability in alkaline media with a half-wave potential of 0.891 V, surpassing Pt/C and control samples derived solely from wsC60 or FMB. When integrated into a zinc-air battery, it also achieves a higher open-circuit voltage and power density than Pt/C. Theoretical calculations reveal that the curved carbon matrix and adjacent Fe3C synergistically modulate the electronic structure of the Fe-N4 moiety, thereby boosting the ORR kinetics. This work highlights the importance of nanoscale architectural design for precise precursor confinement in developing advanced electrocatalysts.
{"title":"Superior Oxygen Reduction on Curved Fe-N4 Sites Enabled by Molecular Infiltration within Self-Assembled Fullerene Microbelts","authors":"Fancang Meng, Huan Wu, Boyu Jia, Kexiang Li, Zhihua Wang, He Zhu, Chao Chen, Qingmin Ji","doi":"10.1039/d5ta09951j","DOIUrl":"https://doi.org/10.1039/d5ta09951j","url":null,"abstract":"The development of Fe-N-C electrocatalysts for the oxygen reduction reaction (ORR) is crucial for sustainable energy technologies, yet achieving a high density of atomically dispersed Fe-Nx sites remains a challenge. Herein, we proposed a novel spatial confinement strategy based on the molecular-level infiltration of iron-coordinated, water-soluble fullerene (Fe/wsC60) into self-assembled fullerene microbelts (FMB). The -NH2/-OH functionalized C60s act as molecular metal chelator and nitrogen source, while the flexible FMB framework facilitates their effective permeation. This nanoscale confinement effectively mitigates Fe aggregation during pyrolysis, yielding a catalyst with abundant atomically dispersed curved Fe-N4 sites alongside fine Fe3C nanoparticles. The resultant (Fe/N@FMB) catalyst demonstrates an exceptional ORR activity and stability in alkaline media with a half-wave potential of 0.891 V, surpassing Pt/C and control samples derived solely from wsC60 or FMB. When integrated into a zinc-air battery, it also achieves a higher open-circuit voltage and power density than Pt/C. Theoretical calculations reveal that the curved carbon matrix and adjacent Fe3C synergistically modulate the electronic structure of the Fe-N4 moiety, thereby boosting the ORR kinetics. This work highlights the importance of nanoscale architectural design for precise precursor confinement in developing advanced electrocatalysts.","PeriodicalId":82,"journal":{"name":"Journal of Materials Chemistry A","volume":"11 4 1","pages":""},"PeriodicalIF":11.9,"publicationDate":"2026-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146115975","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}
Zoya V. Bobyleva, Anastasia M Alekseeva, Sergey V. Ryazantsev, Maria A. Solovieva, Grigorii P. Lakienko, Yana Sultanova, Georgy Peters, Dmitry Aksyonov, Oleg A. Drozhzhin, Artem Abakumov, Evgeny Antipov
The charge storage mechanism of hard carbon anode materials in sodium-ion batteries remains a highly debated topic. Although multiple models have been proposed, their accuracy is still limited, underscoring the need for a deeper investigation. Our study explores the processes behind charge storage using operando powder X-ray diffraction, ex situ small-angle and wideangle X-ray scattering, operando Raman spectroscopy, and ex situ scanning transmission electron microscopy with integrated differential phase contrast imaging. We propose that the exceptional electrochemical performance of hard carbon compared to graphite can be attributed to its curvature-a unique microstructural feature that promotes a high density of defects with electron-withdrawing properties. To demonstrate the significant role of curvature in hard carbon performance, we computationally analyze sodium adsorption using density functional theory. Our experimental and computational findings provide the first empirical evidence of changes in curvature and the interlayer spacing during the charge-discharge cycle. By revisiting previous findings, we aim to address long-standing issues in understanding charge storage mechanism in hard carbon materials.
{"title":"Curvature as the Missing Descriptor of Sodium Storage in Hard Carbon","authors":"Zoya V. Bobyleva, Anastasia M Alekseeva, Sergey V. Ryazantsev, Maria A. Solovieva, Grigorii P. Lakienko, Yana Sultanova, Georgy Peters, Dmitry Aksyonov, Oleg A. Drozhzhin, Artem Abakumov, Evgeny Antipov","doi":"10.1039/d5ta10180h","DOIUrl":"https://doi.org/10.1039/d5ta10180h","url":null,"abstract":"The charge storage mechanism of hard carbon anode materials in sodium-ion batteries remains a highly debated topic. Although multiple models have been proposed, their accuracy is still limited, underscoring the need for a deeper investigation. Our study explores the processes behind charge storage using operando powder X-ray diffraction, ex situ small-angle and wideangle X-ray scattering, operando Raman spectroscopy, and ex situ scanning transmission electron microscopy with integrated differential phase contrast imaging. We propose that the exceptional electrochemical performance of hard carbon compared to graphite can be attributed to its curvature-a unique microstructural feature that promotes a high density of defects with electron-withdrawing properties. To demonstrate the significant role of curvature in hard carbon performance, we computationally analyze sodium adsorption using density functional theory. Our experimental and computational findings provide the first empirical evidence of changes in curvature and the interlayer spacing during the charge-discharge cycle. By revisiting previous findings, we aim to address long-standing issues in understanding charge storage mechanism in hard carbon materials.","PeriodicalId":82,"journal":{"name":"Journal of Materials Chemistry A","volume":"398 1","pages":""},"PeriodicalIF":11.9,"publicationDate":"2026-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146116071","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}
Pengrong Ren, Shuai Zhang, Yang Su, Huimin Guo, Wenjing Qiao, Dianguang Liu, Chen Shen, Fangping Zhuo, Till Frömling
Na1/2Bi1/2TiO3 (NBT) is widely regarded as a multifunctional material, exhibiting dual capabilities as both an insulating piezoelectric material and an oxygen ion conductor. Historically, property tuning has predominantly relied on chemical doping to tailor composition and phase structure. Here, 0.94(Na0.5Bi0.5TiO3)-0.06BaTiO3 (NBT-6BT) ceramics were prepared by flash sintering. X-ray diffraction and scanning electron microscopy analyses indicate that the flash-sintered sample exhibit a heterogeneous grain morphology and features a high internal stress, which drives a rhombohedral-to-tetragonal transition and enhances ferroelectric behavior. Notably, transmission electron microscopy reveals dislocations within the ceramics. Furthermore, impedance spectroscopy demonstrates ionic conductivity in undoped, flash-sintered NBT-6BT ceramics. Molecular dynamics (MD) simulations demonstrates that the enhanced ionic conductivity is associated with dislocation-induced pathways for oxygen diffusion. By showing that stress and dislocation engineering can effectively tune both structural and electrical properties without additional compositional modification, this study presents a compelling alternative to conventional chemical doping strategies for piezoelectric ceramics.
{"title":"Internal stress and dislocation-mediated phase structure and conduction mechanism in flash-sintered Na1/2Bi1/2TiO3-based ceramics","authors":"Pengrong Ren, Shuai Zhang, Yang Su, Huimin Guo, Wenjing Qiao, Dianguang Liu, Chen Shen, Fangping Zhuo, Till Frömling","doi":"10.1039/d5ta10435a","DOIUrl":"https://doi.org/10.1039/d5ta10435a","url":null,"abstract":"Na1/2Bi1/2TiO3 (NBT) is widely regarded as a multifunctional material, exhibiting dual capabilities as both an insulating piezoelectric material and an oxygen ion conductor. Historically, property tuning has predominantly relied on chemical doping to tailor composition and phase structure. Here, 0.94(Na0.5Bi0.5TiO3)-0.06BaTiO3 (NBT-6BT) ceramics were prepared by flash sintering. X-ray diffraction and scanning electron microscopy analyses indicate that the flash-sintered sample exhibit a heterogeneous grain morphology and features a high internal stress, which drives a rhombohedral-to-tetragonal transition and enhances ferroelectric behavior. Notably, transmission electron microscopy reveals dislocations within the ceramics. Furthermore, impedance spectroscopy demonstrates ionic conductivity in undoped, flash-sintered NBT-6BT ceramics. Molecular dynamics (MD) simulations demonstrates that the enhanced ionic conductivity is associated with dislocation-induced pathways for oxygen diffusion. By showing that stress and dislocation engineering can effectively tune both structural and electrical properties without additional compositional modification, this study presents a compelling alternative to conventional chemical doping strategies for piezoelectric ceramics.","PeriodicalId":82,"journal":{"name":"Journal of Materials Chemistry A","volume":"58 1","pages":""},"PeriodicalIF":11.9,"publicationDate":"2026-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146116246","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}
Yu-Xiong Qin, Zutao Pan, Xuan-Xi Liu, Hao-Peng Lu, Lei Xian, Ling-Bin Kong
Layered oxides are considered promising cathode materials for sodium-ion batteries due to their high theoretical capacity and ease of synthesis. Among these, the P2-type Na2/3Ni1/3Mn2/3O2 (NM) cathode has attracted significant interest due to its high theoretical capacity of approximately 173 mAh·g-1. However, when operated at high voltages, NM undergoes a severe irreversible phase transition from P2 to O2, accompanied by irreversible oxygen redox reactions, leading to rapid capacity decay. To achieve suppressed phase transition and enhanced reversibility of the oxygen redox reaction, this study introduces a synergistic doping strategy using Mg, Zn, and Zr, successfully preparing a high-performance cathode material, Na0.67Ni0.28Mg0.025Zn0.025Mn0.62Zr0.05O2 (MZZ–NM). When assembled into a coin-type full cell with a hard carbon anode, the battery exhibits a high energy density of 321.6 Wh·kg-1 at 1C, with energy retention of 82.6% after 100 cycles and an average discharge voltage maintained at 3.3336V, showing negligible decay. Cyclic voltammetry and in-situ XRD results collectively demonstrate that MZZ–NM possesses favorable cation/anion redox reversibility, excellent reaction kinetics, and structural stability. This study provides new insights into the design of high energy density cathode materials for sodium-ion batteries.
{"title":"Trace High-Entropy Doping Enabling High-Stability and High-Energy-Density Sodium-Ion Batteries","authors":"Yu-Xiong Qin, Zutao Pan, Xuan-Xi Liu, Hao-Peng Lu, Lei Xian, Ling-Bin Kong","doi":"10.1039/d5ta09454b","DOIUrl":"https://doi.org/10.1039/d5ta09454b","url":null,"abstract":"Layered oxides are considered promising cathode materials for sodium-ion batteries due to their high theoretical capacity and ease of synthesis. Among these, the P2-type Na2/3Ni1/3Mn2/3O2 (NM) cathode has attracted significant interest due to its high theoretical capacity of approximately 173 mAh·g-1. However, when operated at high voltages, NM undergoes a severe irreversible phase transition from P2 to O2, accompanied by irreversible oxygen redox reactions, leading to rapid capacity decay. To achieve suppressed phase transition and enhanced reversibility of the oxygen redox reaction, this study introduces a synergistic doping strategy using Mg, Zn, and Zr, successfully preparing a high-performance cathode material, Na0.67Ni0.28Mg0.025Zn0.025Mn0.62Zr0.05O2 (MZZ–NM). When assembled into a coin-type full cell with a hard carbon anode, the battery exhibits a high energy density of 321.6 Wh·kg-1 at 1C, with energy retention of 82.6% after 100 cycles and an average discharge voltage maintained at 3.3336V, showing negligible decay. Cyclic voltammetry and in-situ XRD results collectively demonstrate that MZZ–NM possesses favorable cation/anion redox reversibility, excellent reaction kinetics, and structural stability. This study provides new insights into the design of high energy density cathode materials for sodium-ion batteries.","PeriodicalId":82,"journal":{"name":"Journal of Materials Chemistry A","volume":"95 1","pages":""},"PeriodicalIF":11.9,"publicationDate":"2026-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146101880","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：