Nature Communications
·
2025
·Vol. 16
·期 1
·1-11
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IF 15.7
Wang Jingnan,Zhao Kaiheng,Yao Yongbin,Xue Fan,Lu Fei,Yan Wensheng,Yuan Fangli,Wang Xi
Magnetic field effects (MFE) of ferromagnetic spin electrocatalysts have attracted significant attention due to their potential to enhance catalytic activity under an external magnetic field. However, no ferromagnetic spin catalysts have demonstrated MFE in the electrocatalytic reduction of nitrate for ammonia (NO 3 RR), a pioneering approach towards NH 3 production involving the conversion from diamagnetic NO 3 − to paramagnetic NO. Here, we report the ferromagnetic Fe-TiO 2 to investigate MFE on NO 3 RR. Fe-TiO 2 possesses a high density of atomically dispersed Fe sites and exhibits an intermediate-spin state, resulting in magnetic ordering through ferromagnetism. Assisted by a magnetic field, Fe-TiO 2 achieves a Faradaic efficiency (FE) of up to 97% and an NH 3 yield of 24.69 mg mg cat − 1 at −0.5 V versus reversible hydrogen electrode. Compared to conditions without an external magnetic field, the FE and NH 3 yield for Fe-TiO 2 under an external magnetic field is increased by ~21.8% and ~ 3.1 times, respectively. In-situ characterization and theoretical calculations show that spin polarization enhances the critical step of NO hydrogenation to NOH by optimizing electron transfer pathways between Fe and NO, significantly boosting NO 3 RR activity.
研究领域:
材料科学
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化学工程
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of the American Chemical Society
·
2024
·
IF 14.4
Liu Lin,Yunming Xu,Yiting Han,Ruikun Xu,Tongyue Wang,Zemin Sun,Zhenhua Yan
A deep understanding of the mechanism for the spin-magnetic effect on O–H cleavage is crucial for the development of new catalysts for water oxidation. Herein, we designed and synthesized the crystalline Fe-DABDT and Co-DABDT (DABDT = 2,5-diaminobenzene-1,4-dithiol) and optimized an effective magnetic moment to explore the role of the spin-magnetic effect in the regulation of water oxidation activity. It can be found that the OER activity of the catalyst is positively correlated with its effective magnetic moment. Under the external magnetic field, Fe-DABDT with more spin single electrons has a stronger spin-magnetic response to water oxidation than Fe/Co-DABDT and Co-DABDT. The increase in OER current of Fe-DABDT is nearly 2 times higher than that of Co-DABDT. Experimental and density functional theory studies show that magnetized Fe sites could realize nucleophilic reaction, accelerate the polarization of electron spin states, and promote the polar decomposition of O–H and the formation of the O–O bond. This study provides mechanistic insight into the spin-magnetic effect of oxygen evolution reaction and further understanding of the spin origin of catalytic activity, which is expected to improve the energy efficiency of hydrogen production.
研究领域:
化学
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材料科学
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催化反应
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Na Xiao,Ping Han,Zhaoqi Chen,Qiuling Chen
Under the spotlight for their potential to reduce over-potential, photo-assisted Li–O 2 batteries still face a key challenge: the rapid recombination of photo-generated electron-hole pairs, which limits their efficiency. In this study, we address this limitation by designing a Li–O 2 battery that integrates both photo and magnetic field assistance, using an S-scheme MXene/In 2 S 3 /CoFe 2 O 4 heterojunction photocathode. This unique combination enhances visible light absorption and generates a strong built-in electric field, facilitating effective charge separation and boosting photocatalytic activity. During discharge, photo-generated electrons participate in the oxygen reduction reaction, while photo-induced holes contribute to the decomposition of discharge products during charging. Furthermore, the introduction of a magnetic field, confirmed through vibrating sample magnetometer, Mössbauer spectroscopy, X-ray absorption near edge structure, and cyclic voltammetry analyses, enhances electron-hole separation via Lorentz forces and spin–orbit coupling, accelerating the formation and decomposition of Li 2 O 2 . With this synergistic approach, the battery achieves a high specific capacity of 26,500 mAh g −1 , ultra-low oxygen reduction/evolution reaction over-potentials of 0.08 V/0.17 V, and a long cycle life of 2000 cycles with energy efficiency of 98.11 %. This work demonstrates the promising potential of combining photo and magnetic field effects to improve the electrochemical performance of Li–O 2 batteries, opening new avenues for high-performance energy storage systems.
研究领域:
材料科学
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电化学
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能源存储
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
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2022
·
IF 6.76
Yuxi Sun,Yu Wang,Huaxia Deng,Min Sang,Xinglong Gong
To improve the sedimentation stability of carbonyl iron (CI)-based magnetorheological fluid (MRF), a novel MRF with CI/MXene particles as dispersed phase was prepared. CI/MXene particles were prepared by attaching the lightweight MXene nanosheets onto the surface of CI particles (CIPs) as an additive. The micro-morphology, crystal structure and element composition of CI/MXene particles were analyzed by SEM, XRD and XPS characterization respectively, which confirmed the successful synthesis of CI/MXene particles. CI/MXene-based MRF possessed considerable high magnetorheological (MR) effect, and the magneto-induced shear stress was up to 49 kPa. More importantly, the sedimentation ratio of CI/MXene-based MRF was further characterized to evaluate its stability. Experimental results showed that the sedimentation ratio of MRF increased from 75.7% to 98.0% after mixing CIPs with 3 wt% MXene nanosheets. The sedimentation ratio of CI/MXene-based MRF increased by 29.5% compared to CI-based MRF. As a result, the addition of MXene nanosheets significantly improved the sedimentation stability of MRF while maintained high MR effect.
研究领域:
材料科学
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流体力学
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产品关联
DOI
高影响因子
ADVANCED MATERIALS
·
2021
·Vol. 33
·期 30
·2008225
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IF 30.849
Kun Zhang,Jian Zhao,Qingsong Hu,Sijie Yang,Xixiang Zhu,Yaqi Zhang,Ruiqin Huang,Yongfu Ma,Zhenxing Wang,Zhongwen Ouyang,Junbo Han,Yibo Han,Jiang Tang,Wei Tong,Lei Zhang,Tianyou Zhai
Magnetic-field-enhanced spin-polarized electronic/optical properties in semiconductors are crucial for fabricating various spintronic devices. However, this spin polarization is governed by weak spin exchange interactions and easily randomized by thermal fluctuations; therefore, it is only produced at cryogenic temperatures, which severely limits the applications. Herein, a room-temperature intrinsic magnetic field effect (MFE) on excitonic photoluminescence is achieved in CsPbX 3 :Mn (X = Cl, Br) perovskite nanocrystals. Through moderate Mn doping, the MFE is enhanced by exciton–Mn interactions, and through partial Br substitution, the MFE is stabilized at room temperature by exciton orbital ordering. The orbital ordering significantly enhances the g -factor difference between electrons and holes, which is evidenced by a parallel orbit–orbit interaction among excitons generated by circular polarized laser excitation. This study provides a clear avenue for engineering spintronic materials based on orbital interactions in perovskites.
研究领域:
材料科学
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光学
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自旋电子学
✓ 已验证
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2024
·
IF 18.5
Xin Jiang,Rui Wang,Yimin Tang,Weijie Di,Wenxue Wang,Bing Zhao,Libin Yang
Combined contribution of electromagnetic and chemical effects and their synchronous tuning are an effective strategy for constructing semiconductor surface-enhanced Raman scattering (SERS) substrates with ultra-high sensitivity. In this work, a sulfur vacancy-rich MoS 2 flower-like microsphere is successfully prepared for the first time through the combination of morphology regulation and defect engineering strategies, achieving a synchronous contribution of electromagnetic and chemical effects to SERS enhancement. SERS enhancement factor is as high as 2.54 × 10 8 , which represents the highest sensitivity among the currently reported semiconductor SERS-active substrates. The theoretical calculations and experiments elucidate the observed enhancement activity and the synchronous enhancement mechanism of electromagnetic and chemical effects. The unique flower-like structures of MoS 2 can induce Mie resonance by multiple reflection and scattering of incident light in the cavity structure, which realizes a strong electromagnetic enhancement effect. Meanwhile, a high-efficient carrier separation in substrate and a multiple-channel charge transfer mode between substrate and analyte can be achieved by means of abundant surface sulfur-vacancy defects, which provide a strong chemical enhancement effect for target analyte. This work opens up a new idea and perspective for constructing supersensitive semiconductor SERS sensors, ultimately advancing practical application of semiconductor SERS technology.
研究领域:
材料科学
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纳米技术
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光学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Qiwei Zhang,Yazhi Wei,Bin Chen,Han Cui,Baojian Jing,Chongwei Cui,Shan Qiu
Hydrogen production through water electrolysis is hindered by the high kinetic barriers of the oxygen evolution reaction (OER). Here, cactus-like CoFe 2 O 4 in the form of nanosheet-assembled nanowires (CoFe 2 O 4 -NSW@NF) was synthesized to address this challenge. CoFe 2 O 4 -NSW@NF exhibits an excellent OER overpotential of ∼459 mV at 50 mA cm −2 . Under an applied magnetic field of 350 mT, the overpotential further decreases by ∼14 mV. This enhancement is attributed to the nanowires, which modulate the charge density on the nanosheet surface and promote the transition of disordered electrons into a well-aligned higher spin state. In addition, due to the tip-enhancement effect of the nanowires, the interface between the electrode and electrolyte exhibits a localized temperature increase of ∼4℃ and an approximately two-fold amplification of the magnetic field. These changes further intensify the magnetothermal and magnetohydrodynamic (MHD) effects induced by the magnetic field. This work effectively reduces the OER overpotential through the synergistic interaction of morphology and magnetic field, advancing the design of magnetic-effect catalysts for efficient water splitting.
研究领域:
电催化
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能源材料
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物理化学
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纳米材料科学
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可再生能源
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）