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Illustration for the fabrication of PANI-GO-Fe3O4 nanomaterials by hydrothermal method and in-situ polymerization. • The lamellar structure PANI-GO-Fe 3 O 4 was prepared by Fe 3 O 4 nanoparticles embedded in the PANI-coated GO template by in-situ polymerization. • Special lamellar structure effectively improves the adsorption performance of PANI-GO-Fe 3 O 4 ,and the maximum adsorption capacities of CR and MO dyes are 252.7 and 181.0 mg g−1, respectively. • The adsorption behavior is spontaneous and endothermic, and a high adsorption performance of PANI-GO-Fe 3 O 4 is attributed to the interaction of π-π stacking/electrostatic interactions with dyes. • Langmuir adsorption isotherm model indicated the existence of saturated active sites and its chemisorption mechanism. Magnetic separation performance and reproducibility show the superiority of adsorbent materials. Although adsorption by nanomaterial adsorbents represents a promising approach to remove the dye pollutants in water, the easy agglomeration and low recycling has limited such a prospective application. Herein, we developed a lamellar PANI-GO-Fe 3 O 4 hybrid nanosheet adsorbent by an in-situ polymerization strategy in a hydrothermal reactor with Fe 3 O 4 as an intercalant and GO (graphene oxide) as a template for PANI. Besides the merits of easy magnetic separation ability, the PANI-GO-Fe 3 O 4 hybrid adsorbent also shows a high adsorption capacity of 252.7 and 181.0 mg/g for congo red (CR) and methyl orange (MO) dyes, respectively, quite higher than that of PANI-Fe 3 O 4 and many similar adsorbents in literature. The adsorption behavior followed the quasi-secondary kinetic model and the adsorption isotherms were well fitted with the Langmuir model at 298 K, 313 K and 333 K. After 5 cycles of adsorption and desorption, the removal rates of CR and MO dyes by PANI-GO-Fe 3 O 4 can still reach 88.5% and 76.3%. The superiority of PANI-graphene-Fe 3 O 4 hybrid adsorbent was mainly ascribed to its high dispersibility, thin nanosheets morphology, and π–π stacking/electrostatic interactions with the dyes. This work provides a new direction to promote the separable high-performance adsorbents for removing the ionic dyes contamination from waste water. [ABSTRACT FROM AUTHOR]

Although tremendous efforts have been paid on Ti 3 C 2 T x as a cathode for capacitive deionization (CDI), its structural instability and easy agglomeration have always limited such a promising application. In this study, a hybrid of hollow Ti 3 C 2 T x spheres and flakes was synchronously fabricated by a novel sacrificial-templated method for the first time, and then immobilized/bonded together by in-situ polymerization of polyaniline, which was labelled as S-Ti 3 C 2 T x /PANI/F-Ti 3 C 2 T x. The highest specific capacitance of S-Ti 3 C 2 T x /PANI/F-Ti 3 C 2 T x in 1 M NaCl solution was measured to be 102 F·g−1, and diffusion capacitance of the as-obtained S-Ti 3 C 2 T x /PANI/F-Ti 3 C 2 T x was calculated to be 63%. Thus, a high salt adsorption capacity of 76 mg·g−1 with a maximum salt adsorption rate of 11.45 mg·g−1·min−1 was obtained, which is much higher than that of Ti 3 C 2 T x -related materials in literature for asymmetric CDI system. Moreover, such a superior desalination performance was verified stable at almost 100% after 30 cycles. Besides the ion intercalation and fluoro/hydroxyl groups of Ti 3 C 2 T x , the high performance and stability of the as-obtained S-Ti 3 C 2 T x /PANI/F-Ti 3 C 2 T x should also be ascribed to the beneficial effects of immobilization/bonding role of conductive PANI between S-Ti 3 C 2 T x and F-Ti 3 C 2 T x. This study gives a new perspective to promote the real applications of CDI by designing highly capacitive and stable electrode materials. [Display omitted] • A kind of S-Ti 3 C 2 T x /PANI/F-Ti 3 C 2 T x as intercalation-type pseudo-capacitive cathode electrode was invented. • The S-Ti 3 C 2 T x /PANI/F-Ti 3 C 2 T x electrode has high salt adsorption capacity with 76 mg g-1. • The salt adsorption capacity of S-Ti 3 C 2 T x /PANI/F-Ti 3 C 2 T x electrode remained at almost 100% after 30 cycles. [ABSTRACT FROM AUTHOR]