A “Special” Solvent to Prepare Alloyed Pd₂Ni₁ Nanoclusters on a MWCNT Catalyst for Enhanced Electrocatalytic Oxidation of Formic Acid

Abstract

Herein, an electrocatalyst with Pd2Ni1 nanoclusters, supporting multiwalled carbon nanotubes (MWCNTs) (referred to Pd2Ni1/CNTs), was fabricated with deep eutectic solvents (DES), which simultaneously served as reducing agent, dispersant, and solvent. The mass activity of the catalyst for formic acid oxidation reaction (FAOR) was increased nearly four times compared to a Pd/C catalyst. The excellent catalytic activity of Pd2Ni1/CNTs was ascribed to the special nanocluster structure and appropriate Ni doping, which changed the electron configuration of Pd to reduce the d-band and to produce a Pd–Ni bond as a new active sites. These newly added Ni sites obtained more OH− to release more effective active sites by interacting with the intermediate produced in the first step of FAOR. Hence, this study provides a new method for preparing a Pd–Ni catalyst with high catalytic performance.

Keywords

• Pd₂Ni₁ nanocluster
• doping
• Pd–Ni bond
• deep eutectic solvents
• formic acid oxidation reaction