Efficient Capacitive Deionization of Saline Water by an Integrated Tin disulfide Nanosheet@Graphite Paper Electrode via an in Situ Growth Strategy

Abstract

Capacitive deionization (CDI) is a promising desalination method to address the water resource crisis. However, widely used CDI electrodes mostly rely on carbonaceous nanomaterials and highly complicated slurry-coating processing. It is noteworthy that graphene-like two-dimensional layered metal disulfides with amazing physicochemical properties tend to be promising alternatives. Herein, a novel, integrated, and freestanding SnS2@graphite paper (GP) electrode was rationally designed by a facile solvothermal procedure for CDI application. The texture analyses indicated that as-prepared SnS2@GP displayed a high surface area and a superior open-pore framework. Featuring the SnS2 nanostructure and GP matrix effectively, the SnS2@GP electrode demonstrated an outstanding specific capacitance of 327.66 F/g, favorable electric conductivity, and excellent cyclability. When evaluated as a binder-free electrode for CDI application in a NaCl solution of 500 mg/L and a direct voltage of 1.2 V, the SnS2@GP electrode achieved a high desalination capacity (30.32 mg/g), good adsorption rate, and remarkable regeneration ability. Briefly, the significantly simplified processing and superior desalination behavior make SnS2@GP a promising candidate in water treatment applications.