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Due to the ever-increasing plastic waste causing serious environmental problems, it is highly desirable to recycle it into high-value-added products, such as carbon nanomaterials. However, the traditional catalytic carbonization of hydrocarbon polymers is severely prohibited by the complexity of real-world plastic waste due to the existence of halogen-containing polymers. In this study, through a universal combined template based on magnesium oxide and iron(III) acetylacetonate (Fe(acac)3), a three-dimensional hollow carbon sphere/porous carbon flake hybrid nanostructure is prepared from carbonization of plastic waste with high yields (>70 wt%). This approach is not only suitable for hydrocarbon polymers, but also for halogen-containing polymers. Interestingly, the obtained advanced carbon framework exhibits excellent performance in lithium-ion batteries (802 mA h g−1 after 500 cycles at 0.5 A g−1). The present research paves a new avenue to upcycle plastic waste into a high value-added product. [ABSTRACT FROM AUTHOR]

Solar steam generation is emerging as a promising technology to harvest solar energy for diverse applications such as distillation, desalination, and production of freshwater. However, the synthesis of low-cost and high-efficiency photothermal materials remains a challenge for both industrial and academic research. Here, hierarchically porous carbon having an irregular, inter-connected nanoparticle morphology is facilely synthesized through "controlled carbonization" of low-cost waste poly(ethylene terephthalate) (PET) using ZnCl2/NaCl eutectic salts at 550 °C. We prove that ZnCl2 catalyzes the dehydration and decarboxylation of PET to form vinyl-terminated chain fragments and aromatic rings, which subsequently construct a carbon material frame through further cyclization and crosslinking. Meanwhile ZnCl2/NaCl eutectic salts act as porogens to produce mesopores and macropores. The resultant hierarchically porous carbon shows high specific surface area, fast water transportation, high solar absorption efficiency, and low thermal conductivity. Such combined features endow it with a high evaporation rate of 1.68 kg m−2 h−1 under 1 sun irradiation, an energy conversion efficiency of 97%, and a metallic ion removal efficiency of ca. 99.9% for seawater. More importantly, it outperforms the state-of-the-art carbon-based photothermal materials. This work not only reveals the potential of hierarchically porous carbon for application in solar steam generation, but also gives impetus to the sustainable conversion of low-cost waste polyesters into valuable carbon materials by a "controlled carbonization" strategy for energy storage and conversion, environmental remediation, etc. [ABSTRACT FROM AUTHOR]

A facile and efficient method is used to synthesize porous iron oxide coated with graphene as electrode materials for lithium-ion batteries and supercapacitors. Graphene encapsulation of porous Fe2O3 and Fe3O4 nanorods is directly carried out from FeOOH@GO colloids by taking advantage of an electrostatic self-assembly method, owing to the positively-charged surface of FeOOH and the negatively-charged surface of GO. The combination of graphene and porous iron oxide brings about multifunctional features of the electrode materials as follows: (1) enhanced electrical conductivity makes the electrodes the current collectors; (2) reinforced softness of the electrodes accommodates the large volume changes during charge–discharge cycles; (3) improved high specific surface area of the electrodes increases the accessibility of the active electrode materials to electrolyte; (4) the pores formed by graphene and iron oxide particles facilitate ion transportation; (5) iron oxide particles separate graphene and prevent their restacking or agglomeration, and vice versa, thus improving the immersion and splitting of electrolyte into and out of the electroactive material. Consequently, the porous iron oxide/graphene hybrid nanocomposites deliver a good performance in the electrochemical energy storage for lithium-ion batteries and supercapacitors. [ABSTRACT FROM AUTHOR]

Core–shell hybrid particles, possessing a hard core of silica particles (SiPs) and a soft shell of brushlike polystyrene (PS), were successfully prepared by the combination of lithium–iodine exchange (LIE) and surface-initiated living anionic polymerization (SI-LAP). The molecular weight, graft density and brush thicknesses of the PS brushes were controllable. [ABSTRACT FROM AUTHOR]