Fabrication of 2D Vanadium MXene Polyphenylsulfone Ultrafiltration Membrane for Enhancing the Water Flux and for Effective Separation of Humic Acid and Dyes from Wastewater

MXene, a new 2D transition metal carbide-based material, is gaining outstanding attention in recent days in the area of separation and purification. In this study, we have successfully synthesized vanadium-based MXene-V2CT x (where T represents functional groups such as -OH, O, and F) by etching an aluminum layer from V2AlC. For the first time, a vanadium-based MXene-V2CT x -embedded mixed matrix membrane was fabricated and utilized for removal of hazardous dye and humic acid from wastewater. With an increase in V2CT x loading, the hydrophilicity of the polyphenylsulfone (PPSU) membrane reasonably improved, and its water contact angle was reduced from 82.8 to 70.9°. V2CT x nanosheet-embedded PPSU membrane exhibited an excellent pure water permeability of 247 L m-2 h-1, which was 266% elevated than the pristine PPSU membrane. The V2CT x -PPSU membrane revealed a good antifouling nature, thermal stability, and 98.5% removal of humic acid. The optimal membrane exhibited 96.6 and 82.02% expulsion of Reactive Black 5 (RB 5) dye and Reactive Orange 16 (RO 16) dye, respectively. The flux for RO 16 and RB 5 dyes and humic acid were remarkable with a value of 202.02, 161.61, and 141.41 L m-2 h-1, respectively. This work provides a new V2CT x -incorporated PPSU ultrafiltration membrane to effectively treat humic acid and dye wastewater.

Chemistry, Urease Inhibition, and Phytotoxic Studies of Binuclear Vanadium(IV) Complexes

Vanadium plays an important role in biological systems and exhibits a variety of bioactivities. In an effort to uncover the chemistry and biochemistry of vanadium with nitrogen- and oxygen-containing ligands, we report herein the synthesis and spectroscopic characterization of vanadium(IV) complexes with hydrazide ligands. Substituents on these ligands exhibit systematic variations of electronic and steric factors. Elemental and spectral data indicate the presence of a dimeric unit with two vanadium(IV) ions coordinated with two hydrazide ligands along with two H(2)O molecules. The stability studies of these complexes over time in coordinating solvent, DMSO, indicates binding of the solvent molecules to give [V2O2L2(H2O)2(DMSO)2]2+ (L=hydrazide ligand) and then conversion of it to a monomeric intermediate species, [VOL(DMSO)3]1+. Hydrazide ligands are inactive against urease, whereas vanadium(IV) complexes of these ligands show significant inhibitory potential against this enzyme and are found to be non-competitive inhibitors. These complexes also show low phytotoxicity indicating their usefulness for soil ureases. Structure-activity relationship studies indicate that the steric and/or electronic effects that may change the geometry of the complexes play an important role in their inhibitory potential and phytotoxicity.