Three-level micro–meso–macroporous three-dimensional graphene for highly fast capacitive deionization

Capacitive deionization (CDI) has attracted immense attention in recent years due to its simple energy efficient and eco-friendly desalination process. In capacitive deionization research, limited scale of fabrication for active materials and improving desalination efficiency have been the major challenges. Herein, micro-meso-macroporous three-dimensional graphene (MMM-3DG) with a high surface area (1492.8 m2 g−1) was fabricated in gram-scale production (>1.0 g per one time) as an effective active material for CDI. MMM-3DG exhibited a high electrosorption capacity (9.37 mg g−1) and a fast electrosorption rate (2.79 mg g−1 min−1). Furthermore, MMM-3DG delivered an outstanding rate constant value of 0.071 by a pseudo-second-order kinetic model, and thus low energy consumption value per desalinating ion (33.17 kJ mol−1) during the adsorption process.