Quantification of oxygen surface groups on carbon materials via diffuse reflectance FT-IR spectroscopy and temperature programmed desorption

The aim of this investigation is to quantify surface oxygen groups on an activated carbon by combining the results from temperature programmed desorption (TPD) and diffuse reflectance FT-IR spectroscopy (DRIFTS). A commercial activated carbon was oxidized with ozone to form surface oxygen groups. Afterwards the samples were heated in TPD experiments up to 500 °C. The evolved gases were detected and quantified via IR spectroscopy and DRIFT spectra were collected from the heat-treated samples. Simulation of the DRIFT spectra with a set of Gauss functions led to identification of four surface oxygen groups in the range of 1500–1950 cm−1. Specific concentrations of the four groups can be calculated with the conversion factors obtained by combining TPD and DRIFTS information.