On the importance of steady-state isotopic techniques for the investigation of the mechanism of the reverse water-gas-shift reactionElectronic supplementary information (ESI) available: experimental details. See http://www.rsc.org/suppdata/cc/b4/b403438d/

Abstract
The formation and reactivity of surface intermediates in the reverse water-gas-shift reaction on a Pt/CeO2 catalyst are critically dependent on the reaction conditions so that conclusions regarding the reaction mechanism cannot be inferred using ex operando conditions.