Oxidative Dehydrogenation of Ethane: Superior Nb₂O₅-NiO/Ni-Foam Catalyst Tailored by Tuning Morphology of NiO-Precursors Grown on a Ni-Foam

Large-scale shale gas exploitation greatly enriches ethane resources, making the oxidative dehydrogenation of ethane to ethylene quite fascinating, but the qualified catalyst with unique combination of enhanced activity/selectivity, enhanced heat transfer, and low pressure drop presents a grand challenge. Herein, a high-performance Nb₂O₅-NiO/Ni-foam catalyst engineered from nano- to macroscale for this reaction is tailored by finely tuning the performance-relevant Nb₂O₅-NiO interaction that is strongly dependent on NiO-precursor morphology. Three NiO-precursors of different morphologies (clump, rod, and nanosheet) were directly grown onto Ni-foam followed by Nb₂O₅ modification to obtain the catalyst products. Notably, the one from the NiO-precursor of nanosheet achieves the highest ethylene yield, in nature, because of markedly diminished unselective oxygen species due to enhanced interaction between Nb₂O₅ and NiO nanosheet. An advanced catalyst is developed by further thinning the NiO-precursor nanosheet, which achieves 60% conversion with 80% selectivity and is stable for at least 240 h.