Electrospun porous carbon nanofibers/TiO2 composite coated over carbon cloth- A flexible electrode for capacitive deionization

The combination of porous carbon matrix and metal oxide is trending for capacitive deionization (CDI) due to their synergistic electrochemical behaviour and properties. In this research, a flexible electrode based on electrospun porous carbon nanofibers and TiO2 nanoparticles (particle size -7 nm) i.e., PCNFs/TiO2 composite coated over carbon cloth is developed. A facile in-situ activation procedure using sacrificial polymer is adopted over typical chemical activation treatment to synthesize PCNFs/TiO2 composite. PCNFs/TiO2 composite is prepared in two steps, possessing a high specific surface area of -343 m2 g-1 and pore volume of 0.038 cm3 g-1. Interestingly, CDI unit assembled with PCNFs/TiO2 composite based flexible electrodes delivers the large salt electrosorption capacity of 204.8 mg g-1 at voltage 1.2 V in a salt solution of concentration 500 ppm and conductivity 880 mu S cm- 1. The excellent adsorption capacity retention of 96.4% up to ten adsorptionregeneration cycles can be a tempting option for future flexible CDI applications.

Automated summary

This research developed a flexible electrode based on electrospun porous carbon nanofibers and TiO2 nanoparticles, and synthesized the PCNFs/TiO2 composite through a simple in-situ activation procedure. The composite exhibited a high specific surface area and pore volume, and the CDI unit assembled with the flexible electrodes demonstrated excellent salt electrosorption capacity and stability in high salt concentration and conductivity solutions, making it a promising option for future flexible CDI applications.