Comparison of IRC of carbon/metal oxide composites based in recently published HECDI systems.

Active material	Initial concentration or initial conductivity	V	Ion removal capacity (mg g−1)	Ref.
Graphene aerogel (GA)–TiO2	6000 mg L−1	1.2	24.2	24
Graphene–Co3O4	250 mg L−1	1.6	18.63	6
AC–TiO2	584.4 mg L−1	1.2	17	22
ZrO2–AC	104 mg L−1	1.2	16.35	27
Graphene–Fe3O4	300 μs cm−1	1.6	10.30	25
AC–MnO2	584 mg L−1	1.0	9.3	26
ACC–ZnO	100 mg L−1	1.2	8.5	21
Graphene–SnO2	N.A.	1.4	1.49	28
AC/Co3O4	950 μs cm−1	1.6	40	Present work
AC/Co3O4–Sb2O3–SnO2	950 μs cm−1	1.6	52	Present work