Metal-organic frameworks derived Ce0.3Ni0.7Ox carrier improve Pd dispersion and three-way catalytic performance

The effect of MOFs-derived Ce0.3Ni0.7Ox carrier (CN-M) on Pd dispersion states for three-way catalytic (TWC) performance of natural gas vehicles (NGVs) comparing with Ce0.3Ni0.7Ox carrier (CN-C) prepared by citric acid complexation method has been studied. The results showed that the Pd/CN-M catalyst displayed better Pd dispersion (46.3%) and much higher activity for the conversions of CO, NO and CH4. Both T-50 and T-90 of CO conversion over Pd/CN-M were lower ca. 100 degrees C than that over Pd/CN-C catalyst, T-50 and T-90 of NO conversion were same trend with lower degree ca. 150 degrees C, the CH4 conversion of Pd/CN-M was also much better than that of Pd/CN-C. After thermal aging, the conversions of CO, NO and CH4 of Pd/CN-M had a finite shift with 20-50 degrees C to high temperature. It showed unique structure, smaller crystal particles, higher metal dispersion, stronger reducibility, and higher adsorbed oxygen (O-alpha) on Pd/CN-M catalyst in comparison to Pd/CN-C, and dispersion thermal stabilization of Pd particles on Pd/CN-M catalyst was better than that on Pd/CN-C. This work maybe provides a new method for preparing TWCs with high active for NGVs.

Automated summary

The effect of MOFs-derived Ce0.3Ni0.7Ox carrier (CN-M) on Pd dispersion states for three-way catalytic (TWC) performance of NGVs was compared with Ce0.3Ni0.7Ox carrier (CN-C) prepared by citric acid complexation method. The Pd/CN-M catalyst exhibited better Pd dispersion and higher activity for the conversions of CO, NO, and CH4. It also displayed a better thermal stabilization of Pd particles compared to Pd/CN-C.