Magnetochemistry
·
2024
·Vol. 10
·期 5
·34
·
IF 2.6
Han Zhou,Zaitian Cheng,Zhiqiang Ai,Xinyao Li,Lin Hu,Fapei Zhang
The development of novel synthesis and assembly strategies is critical to achieving a ferromagnetic organic semiconductor with high Curie temperature. In this study, we report a high magnetic field (HMF)-modified solvothermal approach for the reduction in neutral perylene diimide (PDI) into the dianion species to prepare the PDI magnets comprising radical anions after subsequent oxidation processes. The PDI materials, assembled from the dianion solution by an HMF-modified reduction, exhibit a smaller crystallite size and an enlarged distance of the π-π stacking in the PDI aggregates. Furthermore, the PDI magnets obtained from the process under a 9T field reveal weakened ferromagnetism and the rapid degradation of electrical conductivity compared to those prepared without a magnetic field. Based on spectral and structural characterizations, such performance deterioration originates from the enhanced instability of the radical anions exposed to air, as well as the decreased crystallinity for the radical PDIs synthesized from the HMF-modified reduction process. This work demonstrates that magnetic fields offer an effective way in the material synthesis process to manipulate the structure and magnetic properties of the radical-based organic magnets.
研究领域:
材料科学
·
物理化学
✓ 已验证
DOI
高影响因子
CRYSTENGCOMM
·
2025
·
IF 2.6
Qiuyu Fang,Jialiang Luo,Chenghong Zhang,Wei Wang,Wei Ding,Ganhong Zheng,Zhigao Sheng
The phase selectivity and morphology of materials is an effective strategy to improve the electromagnetic wave absorption (EMWA). However, the preparation of EMWA materials with both controllable phase component and adjustable morphology remains a great challenge. Herein, a strategy of phase regulation through high magnetic field is proposed to achieve controllable adjustment of the phase and morphology of iron sulfide, thus promoting interface polarization to improve the EMWA performance. When a high magnetic field is introduced into the reaction, the single Fe3S4 phase is gradually evolved into FeS2 due to the action of magnetizing energy, which presents in the form of Fe3S4/FeS2 composite. And with the increase of magnetic field intensity, FeS2 content increases gradually. In addition, the magnetic field also induces the assembly of Fe3S4/FeS2 and tends to be staggered. Due to the regulation of phase and morphology, accompanied by the redistribution of conductive loss and interfacial polarization, so that the EMWA property of iron sulfide is effectively regulated. 9 T sample with a good impedance matching exhibits a minimum reflection loss value of −50.31 dB, and the effective absorption bandwidth (EAB) is extended to 4.5 GHz. This work has important guidance and inspiration for the design of phase and morphology controlled by the high magnetic field, and it has great application potential in regulating EMWA performance.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2019
·Vol. 11
·期 32
·15023-15028
·
IF 6.97
Chun Wu,Xiaoyang Wang,Wenli Pei,Dong Zhao,Kai Wang,Guojian Li,Qiang Wang
A 6 Tesla high magnetic field (HMF) was separately introduced into the nucleation stage and growth stage and into both stages during the wet-chemical synthesis of FePt nanoparticles. The HMF refined particle sizes and increased the nucleation rate in the nucleation stage and tailored shapes and refined sizes in the growth stage. Extension of nucleation time increased the nucleation rate more than that of the HMF, which increasing was higher enough to tailor the shapes of FePt nanoparticles. Controlling nucleation is a feasible strategy to tailor the shapes and sizes of wet-chemical synthesized nanoparticles.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2020
·
IF 8.758
Xing Yu,Weiwei Zhang,Lu Liu,Yves Fautrelle,Xionggang Lu,Xi Li
The abundant mass and charge transfer involved in Faradaic redox reactions are largely determined by microstructures including the surface area and porosity, elemental composition and electrical conductivity of bimetallic sulfides. Here, a high magnetic field (HMF) was introduced to tune these intrinsic characters for superior supercapacitor electrodes. We developed a novel HMF-controlled anion-exchange methodology to prepare the one-dimensional (1D) bunched Zn–Co–S yolk–shell balls (ZCS6T BYSBs). The HMF-induced directional growth and alignment of Zn0.76Co0.24S drive the directional 1D assembly. The as-obtained ZCS6T BYSBs possess larger surface area/pore volume, higher crystallinity and electrical conductivity, richer electroactive elements, and favorable axial electron and ion transport because of HMF-enhanced favorable ion diffusion and exchange kinetics. Flexible S, N codoped carbon nanotubes/graphene films embedded with the ZCS6T BYSBs (CZS6T/CNTs/SNGS) were fabricated by vacuum filtration and one-step S, N codoping and reduction of graphene oxides to improve structural stability and charge transport. The CZS6T/CNTs/SNGS electrode displayed impressive enhanced specific capacitance and rate capability with 78.7% capacitance retention at 30 A g–1. Furthermore, the CZS6T/CNTs/SNGS//CNTs/SNGS asymmetric supercapacitor delivered remarkable cycling stability with a high energy density of 41.1 W h kg–1 at a large power density of 9022 W kg–1.
研究领域:
材料科学
·
能源存储
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF PHYSICAL CHEMISTRY B
·
2023
·
IF 3.3
Chengyu He,Tie Liu,Peng Miao,Shuang Yuan,Jun Wang,Qiang Wang
Here, we demonstrate that high magnetic fields alter the wettability of water and ionic solutions on the single-crystal α-Al2O3. We investigated the relationship between the substrate crystal orientation, material magnetism, liquid conductivity, and the surface contact angle. Applying high magnetic fields decreased the water contact angles on all of the surface orientations studied, and the reduction was larger for more magnetic substrates. For ionic solutions, high magnetic fields increased the contact angle on the (0001) α-Al2O3 surface but decreased the contact angles on the (112̅0), (101̅0), and (011̅2) surfaces. We attribute these orientation-dependent ionic solution responses to competition between the field-induced sample magnetization energy and the Lorentz force acting on the ionic solution. Overall, this work provides new magnetic-field-based strategies for changing the wettability and provides guidelines for fabricating novel microfluidic systems or biointerfaces with in situ magnetic control.
研究领域:
材料科学
·
物理学
·
化学
·
微流控技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）