The freshwater crisis is undoubtedly one of the major global concerns the world needs to address. Many countries face clean drinking water shortages in the near future due to irresponsible resources management and increasing chemical pollution. The latter is particularly vexing as emerging technologies and industries generate new chemical contaminants continuously. There is an urgent need to develop new and sustainable water purification technologies to reduce chemical water pollution.

Many strategies, such as bioremediation and advanced chemical oxidation, have been proposed to reduce and even completely remove chemical contaminants from natural water sources. Yet, these approaches have low efficacy and often generate unwanted by-products. Conversely, remediation through adsorption is often considered as an effective, cheaper, low energy consumption, easy to operate, and desirable mild alternative remediation solution to other traditional approaches. In this study, we synthesized a new composite by modifying multi-walled carbon nanotubes (MWCNT) with ferrihydrite (FHY), a nanocrystalline oxyhydroxide phase. The composite composition was optimized for the adsorption of contaminants under electrochemical assistance. Our results determined that 36% FHY and 64% MWCNT is the optimum ratio and the estimated maximum electrosorption (with +0.6 V applied potential) capacity (initial of 100 μg.L^-1 PFOA) of FHY/MWCNT under electrosorption was 623 times higher than that obtained without electrosorption. This composite is not only a promising material for water purification technology but also for other related industrial applications requiring materials with high electrochemical capacitance and specific surface areas, such as biosensors technologies, water softening materials, and ingredients for supercapacitors.