Functional zirconium phosphate nanosheets enabled transfer hydrogenolysis of aromatic ether bonds over a low usage of Ru nanocatalysts

Catalytic hydrogenolysis of aromatic ether bonds is a highly promising strategy for upgrading lignin into small-molecule chemicals, which relies on developing innovative heterogeneous catalysts with high activity. Herein, we designed porous zirconium phosphate nanosheet-supported Ru nanocatalysts (Ru/ZrPsheet) as the heterogeneous catalyst by a process combining ball milling and molten-salt (KNO3). Very interestingly, the fabricated Ru/ZrPsheet showed good catalytic performance on the transfer hydrogenolysis of various types of aromatic ether bonds contained in lignin, i.e., 4-O-5, α-O-4, β-O-4, and aryl-O-CH3, over a low Ru usage (<0.5 mol%) without using any acidic/basic additive. Detailed investigations indicated that the properties of Ru and the support were indispensable. The excellent activity of Ru/ZrPsheet originated from the strong acidity and basicity of ZrPsheet and the higher electron density of metallic Ru0 as well as the nanosheet structure of ZrPsheet.