Lei Cai,Fei Pan,Xiaojie Zhu,Yanyan Dong,Yuyang Shi,Zhen Xiang,Jie Cheng,Haojie Jiang,Zhong Shi,Wei Lu
Exploring high-performance microwave absorbing materials with lightweight, thin thickness and strong electromagnetic wave (EMW) absorption capability is an essential way to solve EMW pollution problems. Herein, layered N-doped MXene (Ti 3 CNT x ) flakes and hollow Co-ZIF particles (HCF) hybrids were successfully fabricated using the controllable cooperative protection etching strategy and the electrostatic self-assembly technology . Remarkably, the microwave absorption hybrids achieved ultrathin (1.43 mm), and strong EMW absorption ability (reflection loss of −55.02 dB) with a rather low filler loading, which is superior to the magnetic–dielectric hybrids with similar components reported in the literatures. The synergistic effect generated by the improvement of dielectric loss , magnetic loss and interface polarization could effectively integrate with the impedance matching to improve the attenuation ability of EMW. Therefore, this simple assembly and etching strategy opens a new platform for designing hollow and layered materials and broadens the desirable candidates for lightweight and high-efficient microwave absorbers.
Hang Yu,Dajian Cai,Shiyang Li,Congjie Gao,Lixin Xue
Tight ultra-filtration (TUF) membranes with in-situ grown zeolitic imidazole framework (ZIF) particles embedded in and packed under porous polysulfone (PSF) separating layers were prepared using non-solvent induced phase separation (NIPS) processes. Imidazole ligands contained in casting solutions were released and reacted with divalent Zn 2+ cations pre-loaded on non-woven fabric supporting layers. The capillary filling pore size and molecular-weight-cut-off (MWCO) Stokes solute rejection pore size of the formed ZIF/PSF TUF were tuned by varying the loading levels of Zn (II), polyvinylpyrrolidone (PVP) and imidazole, as well as the NIPS reaction time. With thinned PSF separating layer (200–500 nm) and embedding water permeating short-cuts from the ZIF particles, ZIF/PSF TUF membranes showed 7 times higher water permeance (up to 250 L/(m 2 h bar)) and greatly enhanced dye/salt retention selectivity, bearing high potential for applications in dye and textile waste water treatment processes.
危险品化学品经营许可证（带存储）