College of Chemistry and Chemical Engineering, Southwest Petroleum University, 8 Xindu Avenue, Chengdu, Sichuan 610500, PR China.
College of Chemistry and Chemical Engineering, Southwest Petroleum University, 8 Xindu Avenue, Chengdu, Sichuan 610500, PR China; State Key Lab of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, 8 Xindu Avenue, Chengdu, Sichuan 610500, PR China; Research Institute of Industrial Hazardous Waste Disposal and Resource Utilization, Southwest Petroleum University, Chengdu, Sichuan 610500, PR China.
J Colloid Interface Sci. 2022 Apr 15;612:156-170. doi: 10.1016/j.jcis.2021.12.160. Epub 2021 Dec 29.
Developing the multi-functional membranes including oil/water emulsion separation and removal of hazardous organic pollutants is essential to the purification of the complicated wastewater. However, it remains a daunting challenge to combine these intended functions while maintaining high separation efficiency. Herein, we developed a new 2D lamellar MXene/poly (arylene ether nitrile) (PEN) fibrous composite membrane through the self-assembly of TiO nanoparticles intercalated MXene nanosheets onto the porous PEN nanofibrous mats and bioinspired polydopamine triggered chemical-crosslinking with polyethyleneimine (PEI). Such nano-intercalation and mussel-inspired crosslinking could effectively regulate the interlayer spacing of the MXene nanosheet skin layer and surface wettability of the composite membrane, which also further contributed to the fast separation and unique bifunctional feature. It was found that the MXene@TiO/PEN fibrous composite membrane exhibited low oil-adhesion and superhydrophilic (WCA = 0°)/underwater superoleophobic (UOCA > 155°) properties, which could efficiently separate various surfactant-stabilized oil-in-water emulsions under low pressure of 0.04 MPa while keeping good stability (Under 1 M HCl and 2 M NaOH solutions) and recyclability. Interestingly, the fibrous composite membrane achieved favorable permeation flux of 908-1003 Lmh (2270-2507.5 Lmhbar) in comparison to other reported MXene based multifunctional composite membranes. Moreover, owing to the synergistic effect of MXene nanosheets and TiO nanoparticles, the MXene@TiO/PEN membrane showed excellent photocatalytic degradation performance for various dyes under visible light, i.e. the photocatalytic degradation efficiency for 15 ppm MB, MO, CV, and MeB solutions achieved 92.31%, 93.50%, 98.06%, and 99.30% within 60 min, respectively. Such 2D MXene bio-functional composite membranes with outstanding oil/water emulsions separation and photocatalytic degradation of dyes pave an avenue for treating complicated oily wastewater.
开发包括油水乳液分离和去除危险有机污染物的多功能膜对于复杂废水的净化至关重要。然而，将这些预期功能结合起来同时保持高分离效率仍然是一个艰巨的挑战。在此，我们通过将 TiO 纳米粒子自组装到多孔 PEN 纳米纤维毡上，并通过生物启发的聚多巴胺引发与聚乙烯亚胺（PEI）的化学交联，开发了一种新型二维层状 MXene/聚（芳醚腈）（PEN）纤维复合膜。这种纳米插层和贻贝启发的交联可以有效地调节 MXene 纳米片皮层的层间距和复合膜的表面润湿性，这也进一步有助于实现快速分离和独特的双功能特性。结果发现，MXene@TiO/PEN 纤维复合膜表现出低油附着性和超亲水性（WCA=0°）/水下超疏油性（UOCA>155°）特性，在 0.04 MPa 的低压下可以有效地分离各种表面活性剂稳定的油包水乳液，同时保持良好的稳定性（在 1 M HCl 和 2 M NaOH 溶液中）和可回收性。有趣的是，与其他报道的基于 MXene 的多功能复合膜相比，纤维复合膜的渗透通量高达 908-1003 Lmh（2270-2507.5 Lmhbar）。此外，由于 MXene 纳米片和 TiO 纳米粒子的协同作用，MXene@TiO/PEN 膜在可见光下对各种染料表现出优异的光催化降解性能，即在 60 min 内，对 15 ppm MB、MO、CV 和 MeB 溶液的光催化降解效率分别达到 92.31%、93.50%、98.06%和 99.30%。这种具有出色油水乳液分离和光催化降解染料功能的二维 MXene 生物复合膜为处理复杂含油废水开辟了一条途径。
