Herein,we report the excellent De-NO_(x)performance of La0.7Sr0.3MnO3(LSM)perovskite-supported Pd catalysts(Pd-LSM)in alternating lean-burn/fuel-rich atmospheres using C3H6 as reductant and describe the in situ activa...Herein,we report the excellent De-NO_(x)performance of La0.7Sr0.3MnO3(LSM)perovskite-supported Pd catalysts(Pd-LSM)in alternating lean-burn/fuel-rich atmospheres using C3H6 as reductant and describe the in situ activation of the Pd catalysts via metal-support interaction(MSI)tuning.The NO_(x)reduction conversion of the Pd-LSM catalyst increased significantly from 56.1%to 90.1%and the production of N2O was suppressed.Our results demonstrated that this behavior was mainly attributed to the in situ transformation of Pd2+into Pd0 during the reaction.The generated Pd0 species could readily activate the C3H6 reductant and achieve an eight-fold higher turnover frequency than Pd2+for the reduction of NO_(x).Moreover,excessive MSIs inhibited the in situ generation of Pd0,and thereby,lowered the De-NO_(x)activity of the catalyst even at high Pd dispersion.In addition,the Pd-LSM catalysts exhibited much higher S tolerance than conventional Al_(2)O_(3)-supported catalysts.Our study provides a new approach for analyzing and designing highly active metal catalysts operated under dynamic alternating oxidizing/reducing atmospheric conditions.展开更多
文摘Herein,we report the excellent De-NO_(x)performance of La0.7Sr0.3MnO3(LSM)perovskite-supported Pd catalysts(Pd-LSM)in alternating lean-burn/fuel-rich atmospheres using C3H6 as reductant and describe the in situ activation of the Pd catalysts via metal-support interaction(MSI)tuning.The NO_(x)reduction conversion of the Pd-LSM catalyst increased significantly from 56.1%to 90.1%and the production of N2O was suppressed.Our results demonstrated that this behavior was mainly attributed to the in situ transformation of Pd2+into Pd0 during the reaction.The generated Pd0 species could readily activate the C3H6 reductant and achieve an eight-fold higher turnover frequency than Pd2+for the reduction of NO_(x).Moreover,excessive MSIs inhibited the in situ generation of Pd0,and thereby,lowered the De-NO_(x)activity of the catalyst even at high Pd dispersion.In addition,the Pd-LSM catalysts exhibited much higher S tolerance than conventional Al_(2)O_(3)-supported catalysts.Our study provides a new approach for analyzing and designing highly active metal catalysts operated under dynamic alternating oxidizing/reducing atmospheric conditions.
