Extended Data Fig. 2: Debromination mechanisms via a gaseous and oxide-mediated radical route.

(a) Pyro-GC/MS analysis of 2-bromophenol with the absence and presence of CaO at 600 °C, helium atmosphere. (b) The gaseous debromination route without CaO. Gibbs free energy change for gaseous molecular reaction was calculated at M06-2X(D3)/Def2tzvp level using Gaussian. For reference, the ΔG from VASP calculation is ~69 kcal/mol. (c) One of the CaO promoted debromination routes through C-Br homolysis with lower Gibbs free energy change compared to the gaseous route.