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[Display omitted] • Hydrophobic ZIF-8/SA monolithic materials were fabricated via in situ synthesis. • The cooperation of SA, PDMS, and ZIF-8 significantly enhanced adsorption capacity. • The composites displayed rapid kinetic adsorption. • The composites have remarkable absorption recyclability. Microplastics (MPs), a newly emerging class of environmental contaminants, pose a severe threat to the entire ecosystem. The development of efficient and environmentally responsible adsorbents for removing the MPs is a particularly urgent research. Herein, a kind of monolithic ZIF-8 based adsorbents featuring stable hydrophobicity and micropore-mesopore-macropore hierarchical porous structure were fabricated by in situ growth of ZIF-8 nanoparticles on sodium alginate (SA) framework, and using polydimethylsiloxane (PDMS) as a hydrophobic agent. The monolithic nature of ZIF-8/SA allowed an easy solid–liquid separation process for adsorbents from water environment compared to powdered materials. The hierarchical porous structure ensures a remarkable MPs removal performance. The ZIF-8/SA showed high adsorption capacities of 594, 585, and 282 mg/g for polymethyl methacrylate (PMMA), poly (vinylidene difluoride) (PVDF), and polyvinyl chloride (PVC) respectively, and rapid adsorption kinetic progress within 120 min. The ZIF-8/SA adsorbents also exhibited excellent stability in the presence of interfering ions, acid/alkali, and humic acid, and displayed adsorption performance of > 70 % even in actual aquatic environment such as tap water, river water, and seawater. The results of characterizations showed that the synergistic effect of electrostatic interaction, hydrogen bonding, hydrophobic force, and van der Waals force was the main adsorption mechanism. The well-designed hydrophobic ZIF-8/SA monolithic materials would be promising to rapidly remove the MPs from the water environment. [ABSTRACT FROM AUTHOR]

NaBr-mediated "bait and switch" mechanism can promote the formation of ZnO, and thus etches carbon matrix around the N -dopants. As a result, the fully formed N -doping and intrinsic carbon defect (N/DC) coupling sites can greatly improve capacitive behavior, so an excellent cycling stability with high reversible capacity is realized. [Display omitted] Coupling sites of nitrogen-dopants and intrinsic carbon defects (N/DC) are highly attractive to improve potassium-storage capacity and cycling stability, yet it is hard to effectively construct them. Herein, a novel strategy is proposed to establish abundant N/DC sites in N -doped carbon (ZIF8/NaBr-1-900) by pyrolyzing the mixture of metal–organic framework (ZIF8)/sodium bromide (NaBr). Systematic investigations disclose that the introduced NaBr can promote the full conversion of Zn-N 4 moieties into zinc oxide (ZnO) via a "bait and switch" mechanism. Such formed endogenous ZnO can etch the carbon matrix of the confined domains around the N dopants during pyrolysis process, and meanwhile the released N -atoms from Zn-N 4 moieties can largely form edge-N. As such, these N/DC coupling sites enable the resultant carbon to have a more significant capacitive behavior related to fast K-ion migration and high structural stability, leading to 255.3 mAh/g at 2 A/g with a prolonged cycle lifespan over 2000 cycles. Moreover, the assembled K-full battery presents a high energy density of 171.2 Wh kg−1 and excellent cyclability over 5000 cycles. This NaBr-mediated endogenous ZnO domain-confined etching strategy provides a new insight into the exploration of advanced carbon anode. [ABSTRACT FROM AUTHOR]