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In this study, we propose the production of a thin-film composite (TFC) membrane with efficient antimicrobial properties by modifying it with cellulose nanocrystals (CNC) and silver nanoparticles (AgNP). Two approaches (i.e., “one-pot” and “layer-by-layer”) were employed to incorporate CNC and AgNP onto the membrane surface and their impact on the membrane antimicrobial properties was examined. Firstly, the “one-pot” method involved reacting CNC with AgNO3and NaBH4to form a CNC/Ag hybrid material. This CNC/Ag hybrid was then applied to the TFC drawmembranes using polydopamine (PDA) chemistry, allowing the deposition of both CNC and AgNP in a single step. Secondly, the “layer-by-layer” method involved attaching CNC to the membrane surface using PDA chemistry, which was then followed by an in situreaction of AgNO3and NaBH4to deposit the AgNP directly on top of the CNC layer. Membranes modified with a CNC/Ag hybrid using the one-pot method were able to deactivate 75.7 ± 15.6% of attached E. colicells without detrimental impact to membrane separation performance. The membranes modified using the layer-by-layer assembly demonstrated improved antimicrobial activity when compared to those modified with the one-pot CNC/Ag hybrid, being capable of inactivating 90% of the attached E. colicells. On the other hand, the layer-by-layer modification method led to a significant loss in the membrane's salt rejection capacity. These water-based, straightforward, and simple functionalization strategies can tailor the antimicrobial and anti-biofouling performance of membranes for water treatment applications.

Ammonium salt vanadium precipitation is the main method of vanadium metallurgy at home and abroad, but the traditional ammonium precipitation of vanadium can only obtain high valence of V2O5, and the NH3produced in the calcination process cannot be fully utilized. And the preparation of low-valence vanadium oxide V2O3is long and costly. Self-reduction of thermal decomposition of nitrogen-containing precipitation products to produce V2O3is a novel and short process method that can achieve full utilization of ammonia. NaVO3was used as the vanadium source, choline chloride (C5H14ClNO (ChCl)) was used as the vanadium precipitation reagent, and the vanadium concentration was 30 g/L, n(ChCl)/n(V) = 1.5, the initial pH was 1.5, the temperature was 85°C, the time was 2 h, and the vanadium precipitation efficiency could reach 97.05%. V2O3with purity of 97.98% can be obtained by calcination at 550°C for 3 h in an argon atmosphere. XRD, FTIR, XPS, SEM-EDS were used to characterize the product, which further proved that the final product was V2O3. The electrocatalytic hydrogen evolution reaction (HER) of V2O3in acidic media showed high stability after 1000 cyclic voltammetry (CV) cycles, with a low Tafel slope of 88.5 mVdec−1. The electrochemical double layer capacitance (EDLC) was measured by CV at different scan rates, and the EDLC of V2O3was 1.104 mFcm−2. This study provides a short-flow preparation method for V2O3and can provide predictions for the application of V2O3in HER and supercapacitors.

Microscale swimmers are attractive for targeted drug delivery, noninvasive microsurgery and environmental remediation at different length scales, among which, Marangoni-based swimmers have garnered considerable attention due to their independence of external energy supply. However, applications of most existing chemical swimmers are limited by complex fabrication, high cost, utilization of organic (or even toxic) solvents, poor motility performance, and lack of controllability. To address these challenges, we propose an approach for all-aqueous soft milli-swimmers that utilizes biodegradable hydrogels and biocompatible fuels. This innovative method achieves swimmer body generation and fuel loading in one step by simply dripping one aqueous solution into another, saving fabrication time and minimizing fuel loss during transfer. These all-aqueous soft milli-swimmers have rove beetle-like self-propulsion, which stores low-surface-energy compounds within their body for propulsion on liquid surfaces. Isotropic and anisotropic all-aqueous soft milli-swimmers are formed with precise control over their dimension, morphology, and movement velocity. Through their motion within engineered channels, intricate labyrinths, dynamic air−liquid interfaces, and collective self-assemblies, their remarkable adaptability in complex aqueous environments is demonstrated. Furthermore, the integration of functional nanoparticles endows these all-aqueous milli-swimmers with multifunctionality, expanding their applications in cargo transportation, sensing, and environmental remediation.