Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, No.8 South 3rd Street Zhongguancun, Beijing 100190, China; School of Physical Sciences, University of Chinese Academy of Sciences, No.1 Yanqihu East Road, Huairou District, Beijing 100049, China.
Wenzhou Institute, University of Chinese Academy of Sciences, No.1 Jianlian Road, Longwan District, Wenzhou, Zhejiang 325001, China.
J Colloid Interface Sci. 2021 Dec 15;604:737-745. doi: 10.1016/j.jcis.2021.07.051. Epub 2021 Jul 15.
Oil adsorption is significant for water purification and environmental protection. However, the conventional bulk sorbents face the predicament of uncontrollable motion as well as hydrophobic nature the whole body, which largely restricts their uptake capacity underwater. Hence, novel adsorbent material for high-efficient oil uptake both at the surface and under the water is urgently required.
We presented a phase-transition lysozyme coating approach to fabricate porous carbon nanotube microspheres with tailorable surface wettability areas for versatile oil adsorption. Because of the existence of magnetic nanoparticle in one hemisphere, the multi-sites coating was easily achieved by constantly changing orientations of the magnetic field. Owing to the integration of various hydrophilic functional groups in lysozyme as well as remarkable adhesion to virtually arbitrary materials, the intrinsically hydrophobic surface of the microspheres was partially modified hydrophilic on multiple sites.
It was demonstrated that the unique surface wettability feature and the porous structure enabled the microspheres to adsorb multiple contaminants both floating on the water and underwater. Besides, the magnetic-responsive ability allowed for controllable collection of oil contaminants. These features, along with the reusability, make the porous carbon nanotube microspheres excellent adsorbents for water purification.
吸附油对于水净化和环境保护非常重要。然而，传统的大块吸附剂面临着不可控运动以及整个疏水的困境，这在很大程度上限制了它们在水下的吸收能力。因此，迫切需要用于高效吸收水面和水下油的新型吸附材料。
我们提出了一种相转变溶菌酶涂层方法，用于制造具有可调节表面润湿性区域的多孔碳纳米管微球，以实现多功能的油吸附。由于在一个半球体中存在磁性纳米粒子，因此通过不断改变磁场的方向可以轻松实现多部位涂层。由于溶菌酶中存在各种亲水官能团以及与几乎任意材料的显著附着力，因此微球的固有疏水性表面在多个部位被部分改性为亲水性。
事实证明，独特的表面润湿性特征和多孔结构使微球能够吸附浮在水面上和水下的多种污染物。此外，磁响应能力允许对油污染物进行可控收集。这些特征以及可重复使用性使多孔碳纳米管微球成为水净化的优良吸附剂。
