Synthesis and structural properties of carbon/alumina composites: Practical application in solid phase extraction of explosives

Abstract

Abstract Carbon-inorganic composites belong to group of modern nanomaterials possessing high potential in many applications. Such adsorbents combine characteristics of nonpolar carbon phase and polar inorganic matrix. Both porosity and texture of composites substantially depend on applied carbon precursor, inorganic component and pyrolysis conditions. Novel carbon/alumina composites were prepared using co-polymerization of resorcinol-formaldehyde polymer with fumed Al2O3 and subsequent pyrolysis of derived materials in inert atmosphere at 800 °C. Morphological and structural characteristics of as-obtained initial polymeric and carbon-inorganic nanocomposites were studied using powder X-ray diffraction, scanning electron microscopy, Raman spectroscopy, nitrogen adsorption methods, and temperature-programmed desorption mass spectrometry. The experimental results showed that filler Al2O3 acting as catalyst has significant influence on the resorcinol-formaldehyde polycondensation reaction and further pyrolysis step, therefore affects the structure of carbon-inorganic composites that is evidenced by the changes of specific surface area and porosity. It was shown that the porosity and texture of prepared composites substantially influenced the adsorption/desorption steps of explosives from aqueous samples. The results provide new ideas on the hybrid composites synthesis as well allow one to elucidate the effect of synthesis method on the structural characteristics of materials which can be used as high quality adsorbents in water treatment.