A novel composite electrode with multiple pore structures for efficient treatment of heavy metal ions in capacitive deionization.

Multiple porous carbon materials have great promise and potential in the capacitive deionization (CDI) field. Specific surface area (SSA), pore size distribution, and preparation method of CDI electrode materials are essential for the treatment of heavy metal ions. In this work, PPy composited porous carbon electrodes (hypercrosslinked polymers/polypyrrole, HCPs/PPy) were obtained by one-step crosslinked carbonization preparation and electro-deposition. The diverse pore structure gives the composite electrode a large SSA and excellent adsorption performance. HCPs/PPy-4 gives a high SSA of 251.26 m2/g. In the CDI process, the adsorption capacity of HCPs/PPy-4 for Fe3+, Cu2+, Pb2+, and Ag+ is 20.69 mg/g, 37.81 mg/g, 26.86 mg/g, and 40.95 mg/g. The negative electrode recoveries for the adsorption of the four ions were reached 81.2%, 89.2%, 85.5%, and 100%, respectively. It indicates that HCPs/PPy is a novel and potentially porous carbon electrode for high-performance CDI. • A novel electrode material with diverse porous structure was obtained more easily by one-step preparation. • The contents of micropores, mesopores, and macropores can be adjusted by conditions of the amount of PAM. • Specific capacitance only 15.51% decay after 10 cycles and the regeneration rate was remained at 97.61%. • The adsorption capacity for Ag+, Cu2+, Pb2+, and Fe3+ is 40.95 mg/g, 26.86 mg/g, 37.81 mg/g and 20.69 mg/g. [ABSTRACT FROM AUTHOR]