Biomass-derived carbons and their modification techniques in electrochemical capacitive deionization desalination

Abstract

Capacitive deionization (CDI), a new electrochemical technique, exhibits excellent desalting performance for removing salt from seawater. The desalting performance mainly depends on the electrode adsorption and desorption processes in CDI devices, which are inseparable from the structure of the electrode material. Traditional porous electrode materials are typically carbon-based, and among these materials, biomass-derived carbon has emerged as a promising candidate owing to its abundant raw material sources, structural tunability, and environmental benignity. In this study, the desalination mechanism and process of CDI are comprehensively expounded, and the advantages and disadvantages of each unit structure of CDI are summarized. This study completely analyzes the entire process of biomass-derived carbon materials from raw material selection, pretreatment of precursors, and preparation of bio-derived carbon to modification, providing a complete technical route. By selecting the appropriate CDI unit structure and combining the preparation and modification technologies of biomass materials, it is expected that electrode materials with economical, environmentally friendly and excellent desalination performance can be designed. In addition, this study focuses on the desalination performance of different biomass-derived carbons under various modification technologies, providing scholars with a comprehensive research perspective on modification technologies.