Sonochemical synthesis of Co3O4 nanoparticles deposited on GO sheets and their potential application as a nanofiller in MMMs for O2/N2 separation

Abstract

In this study we report an environmentally friendly, facile and straightforward sonochemical synthetic strategy for a Co₃O₄/GO nanocomposite using N,N′-bis(salicylidene)ethylenediaminocobalt(II) as a precursor and graphene oxide sheets as an immobilization support for Co₃O₄ nanoparticles. The synthesis was facilitated by physical and chemical effects of cavitation bubbles. The synthesized nanocomposite was thoroughly characterized for its composition and morphology using Fourier transform infrared spectroscopy (FTIR), Energy dispersive X-ray spectroscopy (EDS), Scanning electron microscopy (SEM), UV-visible, Raman and X-ray diffraction spectroscopy (XRD), etc. The results show Co₃O₄ nanoparticles of 10 nm (SD 3 nm) were prepared on well exfoliated sheets of GO. The applicability of the synthesized Co₃O₄/GO nanocomposite was optimized as a nanofiller for mixed matrix membranes (MMMs) comprised of poly(2-acrylamido-2-methyl-1-propanesulfonic acid) and polyvinyl chloride. The affinity of the prepared MMMs was evaluated for the separation of O₂/N₂ gases by varying the concentration of nanofiller, i.e. 0.03%, 0.04%, 0.05% and 0.075% (w/v). The results display high separation performance for O₂/N₂ gases with excellent permeance (N₂ 167 GPU and O₂ 432 GPU at 1 bar) and O₂/N₂ selectivity of 2.58, when the MMMs were loaded with 0.05% (w/v) of Co₃O₄/GO nanocomposite.