Investigating the Effect of Variations in One-pot Synthesis on the Properties of Hierarchically Porous Cr/C Monoliths

Described is a facile route for the synthesis of 1 wt% chromium supported on hierarchically porous carbon (1Cr/C) using onepot co-gelation sol-gel method. Addition order of the components is varied in three different ways in order to study the effect on the properties of hierarchically porous 1Cr/C monolithic materials. The materials are characterized by nitrogen sorption, X-ray diffraction (XRD), scanning electron microscopy (SEM), and Raman spectroscopy. The results show a three-dimensional network of disordered carbon with chromium nanoparticles of sizes ranging from 20 nm to 0.5 ?m. The carbon structure was retained at the macropore level, but not at the mesoscale where the ordered mesopores were lost on chromium addition. The chromium nanoparticles were observed to grow on the surface of the ligaments as well as in the carbon matrix. A few significant differences were observed in final materials on varying the addition order during the synthesis in terms of pore size distribution, particle size distribution, and graphitic nature of the final carbon, etc.