A 3D ordered hierarchically porous non-carbon electrode for highly effective and efficient capacitive deionization

Abstract

In this work, three-dimensional ordered mesoporous titanium nitride (3DOM-TiN) has been synthesized via a templating method as a novel high-performance non-carbon capacitive deionization (CDI) electrode material. The dual ion electrosorption mechanisms, fast ion diffusion and rapid charge transfer enabled by the multiple advantageous features of the 3DOM-TiN electrode facilitate an outstanding CDI salt adsorption capacity (SAC) as high as 23.6 mg g⁻¹ and a record-breaking maximum salt adsorption rate (SAR) of 3.2 mg g⁻¹ min⁻¹ in 500 mg L⁻¹ NaCl solution at an applied voltage of 1.2 V. Such excellent CDI performance in addition to excellent cycling stability not only ranks the 3DOM-TiN electrode as one of the most promising electrodes for future CDI applications but also confirms the great potential of nanoengineered non-carbon electrodes for next-generation CDI cells.