Facile synthesis of MoO2 microspheres and their application as ion-to-electron transducers for potentiometric sensors

Abstract

As a representation of metallic transition metal oxide, MoO2 has drawn great attention for its synthesis and application. Herein, MoO2 microspheres with rough surface have been synthesized from MoO3 microrods via a facile solvothermal method for the first time. The structure and morphology of the as-synthesized MoO2 microspheres are characterized, and it has found that the produced MoO2 microspheres have a typical monoclinic structure with a good single-crystalline property. In addition, the obtained MoO2 microspheres with diameters ranging from 0.5 to 2 μm feature with a rough surface characteristic. Comparative experiments are conducted to investigate the reaction mechanism, and it has proved that the presence of H+ is crucial to the fabrication of rough surface characteristic. The as-synthesized MoO2 microspheres have been applied as ion-to-electron transducers for potentiometric sensors. And the fabricated potentiometric sensor exhibits fast potentiometric response and good potential stability, which can be due to the good ion-to-electron transduction ability and high capacitance of the introduced MoO2 microspheres.