Highly Active Polyethylene Glycol Grafted Cellulose Supported Pd Nanoparticles for Glucose Electrooxidation

Abstract

In this study, poly(ethylene glycol) (PEG) grafted cellulose (CE) composite catalyst support material (PEG -CE) was obtained by chemically cross -linking PEG at varying molecular weight and CE with isophorone diisocyanate (IPDI) and 2,4-toluylene diisocyanate (TDI). PEG -CE supported Pd (Pd/PEG-CE) catalyst was prepared by the chemical reduction method. The crystal size of the Pd/PEG-CE catalyst is 4.79 nm and its crystal structure has been determined to be face -centered cubic Pd. Elemental mapping results indicate that Pd was reduced onto PEGCE successfully and uniformly. Pd exists in the elemental and Pd -O form in the catalyst system. The Pd loading rate of Pd/PEG-C_IPDI catalyst was determined as 18.8% by mass. Among the PEG-CEs prepared with TDI and IPDI, PEG4000-CE_TDI and PEG6000-CE_IPDI displayed the highest specific activities of 1.03 and 1.50 mA cm -2 for glucose electrooxidation. With Pd reduction on PEG4000-CE_TDI and PEG6000-CE_IPDI, the specific activities increased to 1.62 mA cm -2 and 6.97 mA cm -2. Pd/PEG6000-CE_IPDI has the highest electrocatalytic activity and stability in this study for glucose electrooxidation and is an encouraging anode catalyst for direct glucose fuel cells.