最近,2023级博士生龙建军,在Applied Catalysis B: Environment and Energy(IF=20.2)发表研究论文,题为“Modulating electronic density of active metal site via MXene intercalated by alkali ions for superior hydrogen production”。
Abstract
As the core of a catalyst, the active site plays a crucial role in determining the activity and selectivity in hydrogen production reactions. Herein, the size and surface electron density of bimetallic alloy nanoparticles (NPs) were engineered by (alkali ions)-intercalated-Ti3C2Tx MXene, in which alkali ions were removed by water after the intercalation of Ti3C2Tx. The intercalation of alkali ions can effectively increase the interlayer spacing of Ti3C2Tx, enhance the surface accessibility, and improve the interaction between active metal species and Ti3C2Tx, resulting in monodisperse, ultrafine, and surface electron-rich active metal NPs. Resultantly, the obtained NiPt/(Li+)-Ti3C2Tx exhibits an exceptional catalytic performance with a turnover frequency (TOF) value of 3200 h−1 toward complete dehydrogenation of N2H4·H2O at 323 K, which is about 43 and 4-times higher than that of pristine NiPt NPs (75 h−1) and them on Ti3C2Tx without alkali ions intercalation (787 h−1), respectively, and surpassing all the reported catalysts for this dehydrogenation reaction. Additionally, this catalyst also shows an ultrahigh catalytic performance (7317 h−1) for complete dehydrogenation of N2H4BH3 under the same reaction conditions. This work for the first time found that the more electrons on the surface of the active center, the better the activity for hydrazine decomposition, providing inspiration for regulating catalytic active sites and designing efficient heterogeneous catalysts to achieve nitrogen-based hydride activation.