Novel electroblowing synthesis of tin dioxide and composite tin dioxide/silicon dioxide submicron fibers for cobalt(ii) uptake

Abstract

Nanoscale SnO₂ has many important properties ranging from sorption of metal ions to gas sensing. Using a novel electroblowing method followed by calcination, we synthesized SnO₂ and composite SnO₂/SiO₂ submicron fibers with a Sn : Si molar ratio of 3 : 1. Different calcination temperatures and heating rates produced fibers with varying structures and morphologies. In all the fibers SnO₂ was detected by XRD indicating the SnO₂/SiO₂ fibers to be composite instead of complete mixtures. We studied the Co²⁺ separation ability of the fibers, since ⁶⁰Co is a problematic contaminant in nuclear power plant wastewaters. Both SnO₂ and SnO₂/SiO₂ fibers had an excellent Co²⁺ uptake with their highest uptake/K_d values being 99.82%/281 000 mL g⁻¹ and 99.79%/234 000 mL g⁻¹, respectively. Compared to the bare SnO₂ fibers, the SiO₂ component improved the elasticity and mechanical strength of the composite fibers which is advantageous in dynamic column operation.