Structural and thermal characteristics of Ni-doped carbosils prepared by mechanochemistry

Abstract

Abstract The paper presents the effects of differentiation of initial matrix (silica gel Si-50 or Aerosil A-200) and the addition of Ni2+ ions (in the form of Ni(NO3)2·6H2O) on structural and thermal properties of carbosils prepared by mechanochemical deposition of carbon matter (potato starch). Porous structure of the initial and modified materials was characterized by the low-temperature nitrogen adsorption/desorption method as well as by PSD calculated from the calorimetric data (DSC) using the thermal effects of phase transitions of water confined in carbosil pores. To evaluate comprehensive properties of the samples, the thermogravimetric (TG, DTG and DTA), spectroscopic (XRD, FTIR/ATR) and microscopic (SEM) investigations were carried out. It was found that mechanochemistry is an appropriate method for rebuilding the porous structure of silicas as well as for homogeneous deposition of carbon matter and catalyst on the silica matrices. It has been shown the nickel doping causes pore volume increase and lowering of carbon deposit thermal stability. The obtained carbosils are mesoporous materials with a small amount of micropores created in the carbon part.