Synthesis, characterization and electrochemical behavior of Sb-doped ZnO microsphere film

• Sb-doped ZnO microsphere (SZM) films were grown by hydrothermal deposition.
• Carboxylate ions were used to form complex during hydrothermal growth.
• The formation of Zn–Sb tartrate complex is the key to realize SZM.
• The biosensors based on SZM film are feasible and sensitive to detect H2O2.
• The Sb doping could improve the electrochemical property of ZnO.

Sb-doped ZnO microsphere film was fabricated by a carboxylate ion assisted hydrothermal route coupled with a post-calcination process. The structure, chemical composition and optical band gap of the Sb-doped ZnO microsphere film were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, inductively couple plasma optical emission spectroscopy and UV–visible spectrophotometry, and compared with the un-doped ZnO microsphere film. The results suggest that the formation of zinc–antimony tartrate complex species during hydrothermal growth is the key to realize Sb-doped ZnO microstructures, and the present hydrothermal method with post-calcination is an effective way to dope Sb into ZnO. Furthermore, the Sb-doped ZnO microsphere film based electrochemical biosensor exhibits a good sensing performance for the detection of hydrogen peroxide, with a sensitivity of 271 μA mM− 1 cm− 2 which is more than three times higher than that of the un-doped ZnO biosensor.