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We demonstrated the deposition of the architecture of graphene oxide on stainless steel substrate and its potential environmental application. The synthesis and characterization of graphene oxide were described. The controlled formation of graphene oxide coatings in the form of the homogenous structure on stainless steel is demonstrated by scanning electron microscopy (SEM). The structure, morphology and properties of the material were assessed by Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, transmission electron microscopy (TEM) and atomic force microscopy (AFM). The morphology and stability of these structures are shown to be particularly related to the pre-treatment of stainless steel substrate before the electrophoretic deposition. This approach opens up a new route to the facile fabrication of advanced electrode coatings with potential use in environmental applications.

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BACKGROUND Clay‐based materials represent great potential for the development of efficient and environmentally friendly sorbents. The study focuses on a laboratory‐obtained manganese dioxide/montmorillonite (MnO2/MMT) composite for removal of two types of antibiotics – amoxicillin (AMX) and ampicillin (AMP) – from aqueous solution. RESULTS The composite was successfully prepared using a reduction procedure involving the reaction between potassium permanganate (KMnO4) and hydrochloric acid (HCl) to form MnO2 followed by the addition of MMT. X‐ray analysis, scanning electron microscopy, X‐ray fluorescence and Fourier transform infrared spectroscopy were performed for characterization of physicochemical and structural properties, simultaneous thermogravimetry and differential scanning calorimetry for estimation of thermal stability and high‐performance liquid chromatography for determination of antibiotic equilibrium concentrations in aqueous solution. The precipitated MnO2 component, manifested by long fibers, corresponded to the tunnel structure of cryptomelane. In the case of MnO2/MMT it is evident that MnO2 developed short fibers with the participation of the MMT matrix. The thermal data suggested that the MnO2 phase upon contact with the clay support showed better thermal stability. The final decomposition of Mn2O3 was shifted to higher temperature of 985 °C. Adsorption procedure in a batch regimen showed sufficient sorption ability for both antibiotics with over 90% efficiency. For AMP the value of qmax was about 45 mg g−1 and for AMX it was only 21 mg g−1. CONCLUSIONS The results provided valuable information for the design of a potentially inexpensive clay‐based adsorbent and demonstrated the removal of two types of broad‐spectrum β‐lactam antibiotics from aqueous solution to a sufficient degree. © 2022 Society of Chemical Industry (SCI).

<p>The main objective of this study is to investigate the changes in structure, surface area and porosity of monomineral fraction of the local bentonite upon heating at 300, 500 and 650 °C. IR spectroscopy, DTA, XRD and N2 adsorption method were employed for the analyses. The non-heated montmorillonite was characterized by a basal spacing of 1.50 nm, after thermal treatment of 0.98 nm. This decrease was attributed to the loss of interlamellar water, finally a phase transformation occured. Changes of the crystal structure related with the decrease of the value of specific surface area and total pore volume.</p>

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