The creation of ultrafine alloy nanoparticles(<5 nm) that can maintain surface activity and avoid aggregation for heterogeneous catalysis has received much attention and is extremely challenging.Here,ultrafine PtRh...The creation of ultrafine alloy nanoparticles(<5 nm) that can maintain surface activity and avoid aggregation for heterogeneous catalysis has received much attention and is extremely challenging.Here,ultrafine PtRh alloy nanoparticles imprisoned by the cavities of reduced chiral covalent imine cage(PtRh@RCC3) are prepared successfully by an organic molecular cage(OMC) confinement strategy,while the soluble RCC3 can act as a homogenizer to homogenize the heterogeneous PtRh alloy in solution.Moreover,the X-ray absorption near-edge structure(XANES) results show that the RCC3 can act as an electron-acceptor to withdraw electrons from Pt,leading to the formation of higher valence Pt atoms,which is beneficial to improving the catalytic activity for the reduction of 4-nitrophenol.Attributed to the synergistic effect of Pt/Rh atoms and the unique function of the RCC3,the reaction rate constants of Pt_(1)Rh_(16)@RCC3 are 49.6,8.2,and 5.5 times than those of the Pt_(1)Rh_(16)bulk,Pt@RCC3 and Rh@RCC3,respectively.This work provides a feasible strategy to homogenize heterogeneous alloy nanoparticle catalysts in solution,showing huge potential for advanced catalytic application.展开更多
基金supported by the National Natural Science Foundation of China (52161135302 and 21674019)the Research Foundation of Flanders (FWO Grant No. 1298323N)+3 种基金the Natural Science Foundation of Shanghai (20ZR1401400)the Shanghai Scientific and Technological Innovation Project (18JC1410600)the Program of Shanghai Academic Research Leader (17XD1400100)the Fundamental Research Funds for the Central Universities and DHU Distinguished Young Professor Program (LZB2021002)。
文摘The creation of ultrafine alloy nanoparticles(<5 nm) that can maintain surface activity and avoid aggregation for heterogeneous catalysis has received much attention and is extremely challenging.Here,ultrafine PtRh alloy nanoparticles imprisoned by the cavities of reduced chiral covalent imine cage(PtRh@RCC3) are prepared successfully by an organic molecular cage(OMC) confinement strategy,while the soluble RCC3 can act as a homogenizer to homogenize the heterogeneous PtRh alloy in solution.Moreover,the X-ray absorption near-edge structure(XANES) results show that the RCC3 can act as an electron-acceptor to withdraw electrons from Pt,leading to the formation of higher valence Pt atoms,which is beneficial to improving the catalytic activity for the reduction of 4-nitrophenol.Attributed to the synergistic effect of Pt/Rh atoms and the unique function of the RCC3,the reaction rate constants of Pt_(1)Rh_(16)@RCC3 are 49.6,8.2,and 5.5 times than those of the Pt_(1)Rh_(16)bulk,Pt@RCC3 and Rh@RCC3,respectively.This work provides a feasible strategy to homogenize heterogeneous alloy nanoparticle catalysts in solution,showing huge potential for advanced catalytic application.
