In this work, a free-standing sodium titanate ultralong nanotube membrane for multifunctional water purification has been prepared. For obtaining this free-standing membrane with good tenacity, one-dimensional (1D) sodium titanate ultralong nanotubes with a diameter of about 48 nm and length of hundreds of micrometers were prepared from TiO 2 nanoparticles by a stirring hydrothermal method, which can be easily assembled into 2D membranes by facile vacuum filtration. After modified with methyltrimethoxysilane (MTMS), the free-standing membrane with hydrophobic surface possesses oil-water separation, self-cleaning and photocatalytic functions at the same time, which is favorable for the recovery of membrane and decontamination of various pollutants including oils, dust, and organic dyes from water. Furthermore, this membrane also exhibits excellent alkaline, acid, and corrosive salt resistance. This free-standing sodium titanate membrane with multifunction has potential applications in efficient wastewater purification and environmental remediation.
Jingjing Chen,Xiaoli Wu,Chongchong Chen,Yihao Chen,Wenpeng Li,Jingtao Wang
Two-dimensional lamellar membranes featuring well-defined nanochannels hold great promise for efficient organics separation. However, the extensively existed non-selective microdefects within laminate architecture would impair separation efficiency and structure stability of membranes. Herein, defect-free metal-organic framework (MOF) lamellar membrane is facilely constructed by triple-needle electrostatic atomization technology. Specifically, one needle atomizes small-sized Cu-TCPP MOF nanosheets (TCPP = meso-tetra(4-carboxyphenyl)porphyrin) to build lamellar skeleton, and the other two needles meantime atomize Cu 2+ and TCPP to secondary-assemble crystals among nanosheets. In this manner, these non-selective microdefects are subtly sutured by the regenerated crystals with identical chemical components, resulting in a defect-free MOF lamellar membrane with enhanced structural stability. Importantly, this novel secondary-assembly method highly enhances the separation efficiency and meanwhile keeps high organics permeation for MOF membrane, with rejection of 93.8% for Rose Bengal (1.2 nm) and acetone permeance of 86.9 L m −2 h −1 bar −1 . In addition, the multipoint connection between nanosheets and crystals ensures excellent surface shearing and compaction resistance for MOF membrane, permitting high and steady operation performance for over 100 h. This secondary-assembly methodology by one-step process to construct defect-free and steady lamellar membrane provides a new avenue for the development of efficient separation membranes .
危险品化学品经营许可证（带存储）