Electrocatalytic Performance of V2O5/Ti Composite Membrane for High-Efficiency Treatment of Ammonia Nitrogen Wastewater

Abstract

V2O5 films were deposited on Ti substrates to create V2O5/Ti composite membranes by using magnetron sputtering with V2O5 as the target. The effect of sputtering temperature (150 °C–450 °C) on the structure and performance of the V2O5/Ti composite membrane was mainly investigated. The results showed that V2O5 films prepared by magnetron sputtering were α-V2O5, exhibiting lamellar particulates with a rather dense structure. Additionally, V2O5 could enter the microporous structure inside Ti substrates while providing reactive centers and microchannels for the degradation of contaminants in electrocatalytic membrane reactor (ECMR). The strong diffraction peak in the XRD of 300-V2O5/Ti membranes indicated that the sputtering temperature of 300 °C was comparatively advantageous for the transformation of V2O5 crystal phase. The 300-V2O5/Ti also had a smaller interface impedance, larger electrochemical active area (1.45 cm2) as well as diffusion coefficient (7.14 × 10−3 cm2 s−1). The ECMR was built by using V2O5/Ti composite membrane and stainless steel mesh to be anode and cathode, respectively. The ammonia nitrogen removal rate of ECMR reached 93.68% with 300-V2O5/Ti as the anode, and the energy consumption was 0.35 kWh/kg (NH4 +-N). In conclusion, V2O5/Ti composite membrane has excellent potential for ammonia nitrogen effluent treatment.