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

Abstract

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 m(2) 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. (C) 2020 Elsevier Ltd. All rights reserved.