Tailoring the performance of Ni-CaO dual function materials for integrated CO2 capture and conversion by doping transition metal oxides

Transition metal oxides (TMOs) doping is proposed as one effective strategy to improve CO 2 capture and conversion performance of Ni-CaO dual function materials (DFMs). The effect of single and binary TMOs doping on structure–property-activity relationships of Ni-CaO DFMs for integrated CO 2 capture and in-situ reverse water gas shift (RWGS) is investigated. ZrO 2 doping enhances the surface basicity and reducibility of Ni-CaO DFMs for improved CO 2 uptakes and reinforced catalytic activity. ZrO 2 doping also endows Ni-CaO DFMs with improved working stability by forming CaZrO 3 solid solution, which acts as physical barrier to retard the agglomeration and sintering of CaO and NiO species. Doping binary metal oxides of ZrO 2 -CeO 2 further boosts the oxygen vacancy concentration in the DFMs for promoted CO 2 activation and conversion and stabilized CO yield. The desired Ni-CaO-6ZrO 2 -6CeO 2 DFMs shows a higher CO 2 conversion of 72.1% and a lower decay rate of 12.0% for CO yield in consecutive cycles.