Preparation of a CAB−GO/PES Mixed Matrix Ultrafiltration Membrane and Its Antifouling Performance

Serious membrane fouling has limited the development of ultrafiltration membrane technology for water purification. Synthesis of an ultrafiltration membrane with prominent anti-fouling ability is of vital importance. In this study, CAB−GO composite nanosheets were prepared by grafting graphene oxide (GO) with a zwitterionic material cocamidopropyl betaine (CAB) with strong antifouling properties. Anti-fouling CAB−GO/PES mixed matrix ultrafiltration membrane (CGM) was prepared by the phase inversion method with polyethersulfone (PES). Due to its electrostatic interaction, the interlayer distance between CAB−GO nanosheets was increased, and the dispersibility of GO was improved to large extent, thereby effectively avoiding the phenomenon of GO agglomeration in organic solvents. Based on the improvement of the surface porosity and surface hydrophilicity of the CAB−GO/PES mixed matrix membrane, the pure water flux of CGM−1.0 can reach 461 L/(m2·h), which was 2.5 times higher than that of the original PES membrane, and the rejection rates toward BSA and HA were above 96%. Moreover, when the content of CAB−GO was 0.1 wt%, the prepared CAB−GO/PES membrane exhibited very high BSA (99.1%) and HA (98.1%) rejection during long-term operation, indicating excellent anti-fouling ability

Design and Construction of Ag@MOFs Immobilized PVDF Ultrafiltration Membranes with Anti-bacterial and Antifouling Properties

In this work, Ag nanoparticle loading Mg(C10H16O4)2(H2O)2(Ag@MOF) composite material was successfully prepared by a facile strategy, and subsequently Ag-MOFs were used to modify the PVDF ultrafiltration membranes to obtain fouling resistance and higher water flux. The as-prepared PVDF membranes were systematically characterized by a series of analytical techniques such as Water Contact Angle (CA), Scanning Electron Microscopy (SEM), and SEM-mapping. Furthermore, the performance of membranes on antibacterial properties, the pure water flux, and fouling resistance was investigated in detail. Those results showed that the membrane modified by Ag@MOFs containing 30% Ag had the higher anti-bacterial performance, and the clear zone could be increased to 10 mm in comparison with that of blank membrane. Meanwhile, the pure water flux of Ag@MOF membranes increased from 85 L/m2 h to 157 L/m2 h, and the maximum membrane flux recovery rate (FRR) of 95.7% was obtained using SA as pollutant, which is attributed to the introduction of Ag@MOF composite material. Based on the above experimental results, it can be found that the Ag-MOF membranes displayed the excellent antibacterial activity, high water flux, and fine fouling resistance. This work provides a facile strategy to fabricate the Ag@MOFs modified membranes, and it shows an excellent anti-bacterial and water flux performance

Metal-organic frameworks-based mixed matrix pervaporation membranes for recovery of organics

Metal-organic framework (MOF)-based mixed matrix membranes (MMMs) have attracted significant attentions for their distinguished characteristics in pervaporation such as enhanced selectivity, increased permeability and improved mechanical strength through the synergistic integration of polymeric matrices and inorganic fillers. Although many publications have emerged in recent years focusing on MOF-based MMMs, this review specifically emphasizes the improvement of MOF-based pervaporation membranes through the design of dimension of fillers and microstructure. The challenges encountered in MOF-based MMMs for pervaporation and the essential requirements for practical separation applications are addressed. A brief summary of strategies is provided for designing MOF-based MMMs with desired microstructure, macrostructure and multicomponent characteristics by using MOFs as fillers. The latest progresses in novel MOF-based MMMs with specific compositions, controllable pore structure and improved compatibility for recovery of organics are also displayed. The broad application prospects of MOF-based MMMs in pervaporation are introduced, including recovery of ethyl alcohol, butanol and other organics. Moreover, the challenges faced in the practical application of MOF-based MMMs for recovery of organics are presented and the promising future directions are outlined

Research on factors influencing the academic entrepreneurial ability of teachers in the digital age: Evidence from China

In the contemporary digital economy, economic development increasingly relies on the innovation and dissemination of knowledge. Academic entrepreneurship, as a direct channel for knowledge dissemination into the marketplace, is significantly influenced by digital technology. Consequently, how to improve academic entrepreneurial ability has become a hot research topic. This study is grounded in the theory of reciprocal determinism within the context of the digital economy. We use the “2019 China Digital Economy Development Index White Paper” and collect data from 1843 survey questionnaires in China to conduct empirical research with a ridge regression model. It primarily focuses on the following individual factors and social environmental factors on academic entrepreneurial ability of teachers (AEAT): digital economy (DE), organizational support (OS), policy environment (PE), and personal learning growth (PLG). First, the findings show that the DE, OS, PE, and PLG have a significant positive impact on improving AEAT. Second, the results also indicate that social environmental factors relative to personal factors will have a greater impact. Finally, this study not only presents the first attempt to establish a connection between DE and AEAT but also holds significant managerial implications for enhancing AEAT within the context of the DE. Despite the increasing body of literature on academic entrepreneurship, the research domain pertaining specifically to AEAT remains fragmented and lacks comprehensive theoretical development. There is a pressing need for more systematic and thorough investigations to unveil the black box of factors influencing AEAT in the context of the DE

Facile Synthesis of Mesoporous Reduced Graphene Oxide Microspheres with Well-Distributed Fe₂O₃ Nanoparticles for Photochemical Catalysis

In this study, we report the fabrication of hollow reduced graphene oxide microspheres with well-distributed Fe₂O₃ nanoparticles (Fe-rGOS) via a spray-drying methodology. l-Ascorbic acid was employed to reduce graphite oxide (GO) and improve velocity of electrons transfer. Because of l-ascorbic acid and the spray-drying procedure, the in situ Fe₂O₃ nanoparticles with a mean size of 5–10 nm were uniformly deposited on rGO support and the rGO migrated to the surface of the drop to form microspheres. The well dispersed nanoparticles not only generated more active sites and interface contact which was beneficial to enhance the stability of catalysts but also acted as pillars between the rGO layers to achieve mesoporous structure. The formed mesoporous frameworks enhanced mass transfer to a large extent and led to the much better catalytic efficiency. Therefore, the prepared Fe-rGOS exhibited a remarkable photocatalytic activity in a wide pH range and superior recyclability with low leaching of iron ions