Journal of Materials Chemistry C
·
2013
·Vol. 1
·期 38
·6129-6135
·
IF 0
Jing Liu,Yiwu Mao,Jianping Ge
Electrically tunable photonic crystals are fabricated by encapsulating magnetically assembled colloidal crystals inside an electrolytic cell, and their reflection decreases or recovers when an electric field is applied or removed. The reflection changes are caused by the change in the order degree of the colloidal crystals, which can be further explained by the migration of Fe3O4 nanoparticles and the change of localized ionic strength in different electric fields. A stronger electric field is needed to tune the colloidal crystals assembled by a strong magnetic field, and a good match between their strengths is significant to improve the sensitivity and reversibility of the reflection switching. Generally, the reflection falls within 1 s and recovers after 4–5 s depending on the field strength. Since the electric field can be well restricted in the space between two electrodes and precisely controlled by the applied potentials, it is possible to fabricate adjacent magnetic photonic crystal cells whose reflection signals can be independently controlled by the electric field, which reveals a possible solution to high-resolution photonic crystal based optical devices.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
Journal of Materials Chemistry C
·
2021
·Vol. 9
·期 35
·11788-11793
·
IF 7.393
Mengqi Xiao,Jingjing Liu,Zhijie Chen,Wenxuan Liu,Chengcheng Zhang,Yingying Yu,Chaoran Li,Le He
Photonic crystal supraparticles (PCSs) obtained by self-assembly of colloidal building blocks hold promise for applications in various areas. The majority of PCSs are based on isotropic colloidal spheres, fundamentally limiting their structural and functional diversity. Herein we demonstrate the magnetic assembly of Janus PCSs with increased complexity from a colloidal mixture of nonmagnetic spheres and magnetic ellipsoids. The key to this strategy is the use of non-uniform magnetic fields to simultaneously induce the phase separation of binary particles and assist the subsequent crystallization of anisotropic magnetic ellipsoids. Due to their different crystalline structures, the nonmagnetic and magnetic regions of Janus PCSs exhibit isotropic and anisotropic optical properties, respectively. Moreover, the structural colour can be tuned by magnetically controlling the orientation of supraparticles. Our study not only produces multi-functional PCSs with novel structures and properties but also provides a new model system for understanding the colloidal assembly of binary mixtures.
研究领域:
材料科学
·
纳米技术
·
光学
·
胶体化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2019
·Vol. 7
·期 47
·15042-15048
·
IF 6.641
Jingjing Liu,Mengqi Xiao,Chaoran Li,Hai Li,Zhiyi Wu,Qishan Zhu,Rujun Tang,Ao Bo Xu,Le He
Self-assembly of non-spherical building blocks offers a potential route to photonic crystal supraparticles (PCSs) with novel structures and optical properties. However, experimental fabrications of anisotropic-particle-based PCSs have rarely been demonstrated owing to the requirement of additional control over the particle orientation during the assembly process. Here, we develop a spatially confined magnetic assembly strategy for the tailored assembly of ellipsoidal particles into PCSs with unusual non-close-packed structures. Detailed studies reveal that the transition of these metastable structures into close-packed structures is kinetically inhibited during the drying process owing to the synergy of spatial confinement and magnetic alignment. Unlike conventional PCSs, the nanoellipsoid-based PCSs exhibit anisotropic optical properties and multiple magneto-optical responses. The present work not only provides a model system for studying colloidal assembly under spatially confined conditions but also greatly extends the family of PCSs with interesting structures and properties, bringing new opportunities for applications in various areas.
研究领域:
材料科学
·
纳米技术
·
光学
·
胶体化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Wenqian Nong,Yinglu Chen,Danyu Lv,Yitao Yan,Xi Zheng,Xianming Shi,Zhen Xu,Weiliang Guan,Jun Wu,Yongguang Guan
Pathogenic bacteria seriously endanger human health. Metal-organic framework (MOF)-enzyme composites are novel antibacterial materials for effective bacterial inactivation. In this study, we develop a MOF-based nanozyme hybrid for synergistic bacterial eradication, which integrates features of bacterial capture, magnetic assembly, lysozyme hydrolysis, and light-triggered thermal generation and carvacrol release. Core-shell nanoparticles (Fe 3 O 4 @ [email protected] 2 -MIL-88B(Fe), FPM; PVP = polyvinylpyrrolidone) are synthesized by loading PVP-modified Fe 3 O 4 to NH 2 -MIL-88B(Fe), and then covalently immobilizing lysozyme onto the FPM surface through enzymatic reaction by microbial transglutaminase. The lysozyme-covered FPM is further employed as a host matrix for loading antibacterial carvacrol to synthesize Fe 3 O 4 @ [email protected] (Fe)–NH-lysozyme/carvacrol (FPMLC) nanozyme hybrid. This FPMLC can capture bacteria by electrostatic attraction and the FPMLC-bacteria composite is then assembled by an extra magnet. The lysozyme layer can degrade peptidoglycan of the bacterial cell wall, and the released carvacrol can disrupt the bacterial cell membrane under near-infrared (NIR) irradiation. Systematic antibacterial results demonstrate that the developed FPMLC nanozyme hybrid at a low dose of 100 μg/mL completely inactivates (100%) both Escherichia coli and Staphylococcus aureus at cell density of 10 6 CFU/mL. This FPMLC exhibits high-efficiency antibacterial efficacy but no significant cytotoxicity in vitro , and therefore provides promising antibacterial applications in biomedical, environmental, and food fields.
研究领域:
材料科学
·
纳米技术
·
生物医学工程
·
微生物学
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药学
✓ 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）