Abstract
Silver quantum dots particles (Ag QDs) and nanoparticles of Magnetite (Fe3O4) were deposited on nanotubes of Bismuth- insitu doped manganese oxide (Bi-MnOx) with porous morphologies via olymer assisted precipitation processes. The Ag QDs particles of very fine particle size and Fe3O4 nanoparticles were incorporated into the Bi-MnOx polymer composite via high power ultra-sonication deposition technique. Spherical nanoparticles of silver (5-15 nm) were deposited on the porous Bi-MnOx surfaces, whereas, in the case of the Fe(3)O(4 )which was deposited on Bi-MnOx nanotube composite in the form of nanorods, iron oxide particles were loaded into the tubular structure of the Bi-MnOx. The formation of nanotubes and the incorporation of nanorods were confirmed by the SEM and HR-TEM images. The diffuse reflectance spectra indicate a decrease in the bandgap of the composite after the incorporation of Fe3O4 nanoparticles into the Bi-MnO x nanotube . The nanoparticle-modified Bi-MnOx composite electrode was further characterized for hydrogen peroxide electrochemical sensor applications. Fast removal of toxic hexavalent chromium degradation reaction was carried out on the as-prepared Fe3O4- and Ag QDs particle-modified Bi-MnO x nanotube composites. An efficient sorption and removal of Cr (VI) (above 90% conversion) was achieved within 60 min of reaction on the Ag nanoparticle modfied Bi-MnOx. The results obtained show that the Ag@BiMnOx, and Fe3O4-modified porous Bi-MnOx nanotube composite materials demonstrated effective sensing and hexavalent chromium removal activity. (C) 2020 Elsevier B.V. All rights reserved.