Metal-organic frameworks derived tin-doped cobalt oxide yolk-shell nanostructures and their gas sensing properties

Yolk-shell nanomaterials with controlled morphology have received great attention because of their promising applications in gas sensing. Here, we reported the facile synthesis of pure and 1-5 mol% Sn doped Co3O4 yolk-shell nanostructures by calcinating the Co based metal-organic framework (MOF, ZIF-67) prepared from hydrothermal method. The morphologies of the as-obtained samples were characterized by various experimental techniques. Furthermore, the gas sensing properties were systematically measured. Gas sensors based on 3 mol% Sn doped Co3O4 yolk-shell nanostructures exhibited extremely enhanced response to ethanol at 200 degrees C (R-g/R-a = 13.4-100 ppm at 200 degrees C) and low detection limit (R-g/R-a = 1.3-1 ppm ethanol at 200 degrees C). Most importantly, the gas response to 100 ppm ethanol is still maintained well after continuous measurement for 20 days. (C) 2018 Published by Elsevier Inc.