Preparation of corn starch-based monolithic porous carbons

Corn starch-based monolithic porous carbons were prepared by gelatinization of corn starch with or without nickel acetate as a structure modifier, followed by freeze drying and carbonization. The effect of gelatinization parameters such as the concentrations of the starch and addition of nickel acetate on the pore structures of the monoliths was investigated. It was found that the crystallinity of the gelled starch was lower than that of the pristine starch. The concentrations of the starch and nickel acetate simultaneously had an important influence on the pore structure of the gelled starch and the porous carbon monoliths produced. The gelled starch or Ni-doped gelled starch can be obtained using a 10 mass% starch concentration without or with the addition of 0.1 mol/L nickel acetate. The carbon monoliths derived from the Ni-doped or undoped gelled starch had a semi-closed or open pore structure. The semi-closed pores resulted from a severe volume contraction of nearly 80% with the addition of nickel acetate.