Tailor the crystal planes of MIL-101(Fe) derivatives to enhance the activity of SCR reaction at medium and low temperature.

Mainly exposed crystal facets and controllable morphology play a key role in the final performance of the preparation of specific nanomaterials. In the present study, a metal-organic framework pyrolysis method without adding solvent modifiers was developed. By adding CO in the calcination atmosphere to change atmosphere ratio, FeO nanostructures are exposed with different crystal planes and evaluated their performance in NH-SCR reaction. This study proves that SCR catalytic activity of FeO nanocrystals is dependent on morphology and crystal facet. Compared with materials exposed (100), catalysts with more (111) show stronger deNO performance. The preferential exposure of FeO (111) crystal facets increases the concentration of adsorbed oxygen on the catalyst, showing higher surface acidity, and enhances the interaction among NO, O and catalyst, which is conducive to SCR reaction. This is supported by DFT calculations. The results present a great application prospect in preparing nanomaterials with specific crystal structures to effectively treat pollutants.