Starch\nDerived Porous Carbon Nanosheets for High-Performance\nPhotovoltaic Capacitive Deionization

Abstract

Capacitive\ndeionization (CDI) is an emerging technology that uniquely\nintegrates energy storage and desalination. In this work, porous carbon\nnanosheets (PCNSs) with an ultrahigh specific surface area of 2853\nm²/g were fabricated by the simple carbonization of starch\nfollowed by KOH activation for the electrode material of photovoltaic\nCDI. The CDI cell consisting of PCNSs electrodes exhibited a high\nsalt adsorption capacity (SAC) of 15.6 mg/g at ∼1.1 V in 500\nmg/L NaCl as well as high charge efficiency and low energy consumption.\nKOH activation played a key role in the excellent CDI performance\nas it not only created abundant pores on the surface of PCNSs but\nalso made it fluffy and improved its graphitization degree, which\nare beneficial to the transport of ions and electrons. PCNSs are supposed\nto be a promising candidate for CDI electrode materials. The combination\nof solar cells and CDI may provide a new approach to reduce the energy\ncost of CDI and boost its commercial competitiveness.