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New carbon/ZnO/Li₂O nanocomposites with enhanced photocatalytic activity.

ABSTRACT: Our study was focused on the synthesis of photocatalytic materials for the degradation of organic dyes based on the valorization of biomass resources. The biochar resulted from pyrolysis process of cherry pits wastes was activated by CO₂ flow. Activated and inactivated carbon was used to obtain carbon-based photocatalysts impregnated with different zinc salt precursors. The activation of carbon had no significant influence on the photodegradation process. The doping procedure used Li₂CO₃ and Zn(CH₃COO)₂ of different concentrations to impregnate the biochar. The carbon-ZnO-Li₂O based nanomaterials were analysed by TEM and SEM, while the presence of hexagonal wurtzite ZnO was investigated by XRD. The solid samples were analysed by PL at 360?nm excitation fixed wavelength to correlate their morphology with the optical and photocatalytic properties. The presence of Li atoms led to photocatalytic activities of the doped ZnO similar to the undoped ZnO obtained at higher concentrations of zinc acetate precursor.

SUBMITTER: Diacon A

PROVIDER: S-EPMC6856305 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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