Synthesis of molecular imprinted polymer modified TiO2 nanotube array electrode and their photoelectrocatalytic activity

A tetracycline hydrochloride (TC) molecularly imprinted polymer (MIP) modified TiO2 nanotube array electrode was prepared via surface molecular imprinting. Its surface was structured with surface voids and the nanotubes were open at top end with an average diameter of approximately 50 nm. The MIP-modified TiO2 nanotube array with anatase phase was identified by XRD and a distinguishable red shift in the absorption spectrum was observed. The MIP-modified electrode also exhibited a high adsorption capacity for TC due to its high surface area providing imprinted sites. Photocurrent was generated on the MIP-modified photoanode using the simulated solar spectrum and increased with the increase of positive bias potential. Under simulated solar light irradiation, the MIP-modified TiO2 nanotube array electrode exhibited enhanced photoelectrocatalytic (PEC) activity with the apparent first-order rate constant being 1.2-fold of that with TiO2 nanotube array electrode. The effect of the thickness of the MIP layer on the PEC activity was also evaluated.