Study on the fabrication and photoelectrochemical performance of the F− doped Ti/Co3O4 electrodes with n-type semiconductor characteristics

Herein, the Ti/Co 3 O 4 electrodes with n-type semiconductor characteristics were fabricated by a typical hydrothermal process using F − ion as dopant, and their morphology control was also performed by tailoring the hydrothermal temperature. The F − doped Ti/Co 3 O 4 electrodes could be used as photoanode to degrade anthraquinone dye (reactive Brilliant Blue KN-R), and showed excellent photoelectrocatalytic (PEC) activity. It is proposed that the fast ions and electron transportation, high oxygen evolution potential, lower resistance, large active area, and good electrolyte infiltration are responsible for the improved PEC activity of the F − doped Ti/Co 3 O 4 system. Nevertheless, the F − doped Ti/Co 3 O 4 electrode with divergent flower-like structure composed of needle nanowires exhibited highest PEC activity than that of other electrodes. It is noteworthy that the presence of electrostatic anti-barrier arises from an “ohmic” contact between the metal (Ti) and the semiconductor (Co 3 O 4 ) is also an important factor for the higher PEC activity of the F − doped Ti/Co 3 O 4 electrodes. The work provides unique insight into the design of Co 3 O 4 photoanode from a perspective of tailoring the ion doping and morphology.