Hierarchical carbon fiber cloth (CFC)/Co3O4 composite with efficient photo-electrocatalytic performance towards water purification

Abstract

Photoelectrocatalysis (PEC) technology is one of the most effective means to remove color and organic pollutants from dyeing wastewater. In this work, hierarchical carbon fiber cloth (CFC)/Co3O4 composites are fabricated by a simple hydrothermal method and are employed as photoanode to treat simulated reactive dyeing effluent. The effect of hydrothermal temperature on the structure of as-obtained composites is investigated to achieve higher removal efficiency. The findings show that the morphology and surface coverage of Co3O4 on the CFC surface can be regulated by controlling the hydrothermal temperature. It is found that the CFC/Co3O4 composite prepared by the hydrothermal temperature of 120 °C (CFC/Co3O4-120 °C) has a more regular nanowire array structure and higher surface coverage, as compared with that of other hydrothermal temperatures. The as-obtained CFC/Co3O4-120 °C composite shows an excellent decolorization rate (as high as 94%) towards degrading simulated reactive dyeing effluent (reactive Brilliant Blue KN-R). The improvement in PEC activity of the CFC/Co3O4-120 °C composite can be ascribed to its higher active surface area, lower charge transfer resistance, and higher generation efficiency of hydroxyl radicals in comparison with other samples. Therefore, CFC/Co3O4-120 °C is expected to be a suitable anode material for PEC degradation of dyeing wastewater.