Capillary Melt Method for Micro Antimony Oxide pH Electrode

Abstract

Abstract In this work, a new approach named “capillary melt method” was developed to fabricate micro antimony wires, and the wire surface was then oxidized in a nitrate melt at high temperature to obtain an antimony/antimony oxide pH electrode. Characterization results show that the oxide layer on the wire surface is porous, and consists of Sb 2 O 3 crystal phase. The pH electrode, made using this method, showed good sensing performance in buffer solutions in the tested pH range of 2–12. Its EMF signal was found to have a linear relationship with pH value of the solution, with a sensitivity of 54.1 mV/pH and a fitting correlation coefficient of R 2 =1.00. The advantages of the electrode are long‐term stability, fast response, reproducibility and low cost.