The experiments reported in the literature examined the reaction close to atmospheric conditions while our experiments were performed under high vacuum. The carbon surface has a much lower O-atom coverage in our experiments; hence, we would predict a much higher activation energy for the Boudouard reaction. However, the activation energy we obtained from our fits is around 40 kJ mol -1 (TD-slow1 in Fig. ). The maximum possible activation energy from the data can be estimated by using the rate from the residual fit method at 1023 K and the simultaneous fit method at 1823 K. The maximum possible activation energy estimated from our experiments is 65 kJ mol -1 , which is considerably lower than those reported in the literature.