Hydrophilic swellable metal-organic framework encapsulated Pd nanoparticles as an efficient catalyst for Cr() reduction

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Vol. 4; no. 3; pp. 1168 - 11687
• Main Authors: Li, Hong-Chao, Liu, Wu-Jun, Han, He-Xing, Yu, Han-Qing
• Format: Journal Article
• Language: English
• Published: 01.01.2016
• Subjects: Catalysts; catalytic activity; chromium; coordination polymers; Durability; Encapsulation; formic acid; hydrophilicity; Metal-organic frameworks; Nanoparticles; Nanostructure; Palladium; pollutants; Reduction; toxicity
• DOI: 10.1039/c6ta03688k
• ISSN: 2050-7488; 2050-7496

Controllable integration of metallic nanoparticles and metal-organic frameworks (MOFs) may create a new material with multifunctional applications. In this work, an emerging type of core-shell nanostructure, in which metallic Pd nanoparticle cores were encapsulated by MOF (ZIF-67) shells, was facilely synthesized through an impregnation-reduction process. The as-synthesized Pd@ZIF-67 material, with highly dispersed Pd nanoparticles encapsulated in the porous ZIF-67 structure, exhibited favorable catalytic performance towards the formic acid (HCOOH)-induced reduction of highly toxic hexavalent chromium (Cr( vi )). In this process Cr( vi ) was converted to Cr( iii ) within 5 min, and the material could be reused 10 times without significant loss of its catalytic activity. The highly hydrophilic and swellable nature of the ZIF-67 was proposed to be responsible mainly for the favorable durability of the Pd@ZIF-67. The results provided in this work may pave a way for the concise preparation of nano-hybrid catalysts with high performance and durability for pollutant elimination. An emerging type of core-shell nanostructure, in which metallic Pd nanoparticle cores were encapsulated by MOF (ZIF-67) shells, was facilely synthesized through an impregnation-reduction process.