Capacitive deionization (CDI) is a competent water desalination technique offering an appropriate route to obtain clean water. However, a rational designed structure of the electrode materials is essentially required for achieving high CDI performance. Here, a novel sponge‐templated strategy is developed for the first time to prepare graphene sheets with high specific surface area and suitable pore size distribution. Sponge is used as the support of graphene oxide to prevent the restack of graphene sheets, as well as to suppress the agglomerate during the annealing process. Importantly, the as‐fabricated graphene sheets possess high specific surface area of 305 m2 g−1 and wide pore size distribution. Ultrahigh CDI performance, a remarkable electrosorptive capacity of 4.95 mg g−1, and siginificant desorption rate of 25 min, is achieved with the sponge‐templated prepared graphene electrodes. This work provides an effective solution for the synthesis of rational graphene architectures for general applications in CDI, energy storage and conversion.

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A three-dimensional porous graphene electrode is prepared by using cellulose acetate as a template. The electrode possesses ideal porous structure and large surface area, therefore resulting in high electrosorption capacity for CDI application.

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Capacitive deionization (CDI) is a competent water desalination technique offering an appropriate route to obtain clean water. On page 3917, Y.‐M. Yan, K.‐N. Sun and co‐workers design and prepare a 3D‐structured, graphene‐based electrode using sponge (polyurethane, PU) as a template. The electrode possesses a large surface area, wide pore size distribution from nanopores to micropores, and low internal resistance, therefore exhibiting a remarkable electrosorptive capacity of 4.95 mg g−1 and a desorption rate of 25 min.

a b s t r ac tCapacitive deionization (CDI) offers a green and efficient strategy of supplying sustainable clean water. Up to now, high-performance carbon electrode has been substantially pursued for developing advanced CDI technology. In this work, a surfactant-assisted freeze-drying route is reported for the facile synthesis of porous graphene electrode based on the hydrothermal reduction of graphene oxide with ascorbic acid in the presence of sodium dodecyl sulfate (SDS), followed by a freeze-drying treatment. The obtained porous graphene (defined as SRGO) is characterized by scanning electron microscopy, X-ray powder diffraction, elemental distribution analysis, Brunauer-Emmett-Teller adsorption isotherm and Raman spectra. The SRGO exhibits ideal pore size distribution and specific surface area, while the effects of the surfactant on the graphene structural properties are investigated. When used as CDI electrode, the SRGO shows a promising electrosorptive capacity of 5.38 mg·g, an excellent recyclability (64 min for regeneration), and a remarkable salt removal efficiency of 15.85%. This work opens up a facile and variable route to rationally tailor structural properties of graphene for water treatment applications.