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Designing efficient membranes for desalination to help reduce the water shortage crisis has been the subject of various studies. In this study, first, CuAl LDH nanosheets were prepared and the surface of some thin-film composite (TFC) membranes was modified by them. Afterward, the novel heterostructure nanocomposite consisting of CuAl LDH and WS2 nanosheets was synthesized by hydrothermal method, and a new kind of thin-film nanocomposite (TFN) membranes were made using them. All the obtained membranes performance was studied in the forward osmosis (FO) process. The effects of the prepared compounds on the morphology, chemical structure, hydrophilicity, and topology of the polyamide (PA) active layer were evaluated by scanning electron microscopy (SEM), FT-IR spectroscopy, energy-dispersive X-ray (EDX), powder x-ray diffraction (XRD), water contact angle (WCA) goniometer and atomic force microscope (AFM) analysis. Finally, by comparing the results for both types of modified membranes, the membrane containing 0.025 wt% of the nanocomposite modifier showed the highest water flux (29.30 LMH) and selectivity (0.38 g/L) that was chosen as the optimal membrane. Also, the anti-fouling properties of this membrane were studied and the obtained results showed an increase in the fouling resistance compared to the membrane without filler. [ABSTRACT FROM AUTHOR]

The fabrication of some new high-performance WS 2 -Cys-MOF-incorporated thin-film nanocomposite (TFN) forward osmosis (FO) membranes for use in desalination applications is reported. Herein, WS 2 -Cys-MOF nanosheets are synthesized through UiO-66-(CO 2 H) 2 grafting on WS 2 -Cys and integrated into the PA selective layer of TFN membranes. The nanofillers content in the MPD aqueous solution was varied from 0 to 0.25 wt% to acquire the optimal loading and the best FO performance. The presence of polymer-matrix compatible WS 2 -Cys-MOF in the PA selective layer led to the formation of a defect-free smooth surface with additional channels within this layer, which can boost water flux and fouling resistance of TFN membranes. The TFN-0.1 membrane containing 0.1 wt% WS 2 -Cys-MOF results in the best FO desalination performance. Compared to the virgin TFC membrane, its water fluxes are almost doubled with a slight increase in the selectivity ∼18% evaluated under AL-FS orientation using 1 M NaCl as the draw solution and deionized water as the feed solution. Moreover, in the fouling test, this optimum TFN-0.1 membrane with a flux decline of 7.63% revealed a ∼1.4-fold enhancement in anti-fouling tendency. Hence, these high-performance WS 2 -Cys-MOF-incorporated TFN membranes show excellent potential for commercial utilization in the FO-desalination application. • FO membranes were modified using WS 2 -Cys- UiO-66-(CO 2 H) 2 nanocomposite. • The incorporated nanocomposite provided a hydrophile and smooth surface for the polyamide active layer. • WS 2 -Cys- UiO-66-(CO 2 H) 2 nanocomposite modified membranes exhibited better selectivity than TFC membranes. • TFN-0.1 membrane as the optimal membrane showed higher anti-fouling properties compared to the TFC membrane. [ABSTRACT FROM AUTHOR]

Hereby a simple, low-cost and scalable route is being presented for preparation of binder-free electrodes of reduced graphene oxide (RGO) on Ni foam (Ni/Gr). In this regard, the Ni foams are dipped in graphene oxide (GO) slurry. Next, the GO loaded Ni foams are kept in a freeze dryer for 24 h and heated up to 800 °C in an inert atmosphere. In this approach, the amount of active materials can be easily optimized for capacitive deionization (CDI). The characterization of Ni/Gr electrodes revealed a 3D porous assembly of RGO on Ni substrate which is helpful for the fast ion diffusion and rapid electron transport. The electrochemical performance of the prepared electrodes is investigated in both 3-electrode system and symmetric 2-electrode assembly. Then, the prepared electrodes are applied for capacitive deionization (CDI) studies in saline water samples. Results revealed a specific capacitance of about 77 F/g (in 1 M of NaCl at 2.5 A/g) and an ion removal capacitance of 22.3 mg/g (in 50 mL of 500 ppm of NaCl) for the fabricated system. The stability of the CDI system was surveyed in 500 ppm of NaCl solution which showed 65% of the initial capacity after 200 consecutive cycles (9 days). These results indicate that this method is efficient for both supercapacitive energy storage applications and CDI technology. [Display omitted] • Simple binder-free porous graphene on Ni substrate electrodes is synthesized. • The amount of active materials can be easily optimized for capacitive deionization. • Electrochemical adsorption capacity of the electrode is 22.3 mg/g in 500 ppm NaCl. • The electrochemical properties of electrode are compared with PVDF containing electrode. • Electrodes showed 65% of the initial capacity after 200 cycles (9 days) of capacitive deionization. [ABSTRACT FROM AUTHOR]