Structural features of carbons produced using glucose, lactose, and saccharose

Abstract

Glucose, lactose, and saccharose were used as precursors to prepare chars at 400°C then activated at 800°C or 1000°C in closed vessels with controlled amounts of oxygen penetrating through nanopores in the vessel walls. There are correlations between the porosity, amounts of residual O- and H- containing functionalities, and electroconductivity of amorphous carbons studied. The pore size distributions calculated using the nitrogen adsorption isotherms and TEM images show that all carbons are mainly nanoporous with certain contribution of narrow mesopores (at pore half-width x < 5 nm). Oxidizing activation by oxygen penetrating into the closed vessels with chars through nanopores can more strongly change the outer layers of char particles than the inner pores. Therefore, despite relatively great burn-off degree the textural characteristics are relatively low for activated carbons.