Electrocatalytic oxidation of formic acid on Pd/CNTs nanocatalysts synthesized in special "non-aqueous" system.

• A friendly strategy for fabricating Pd particles on MWCNTs supported catalyst. • The reaction condition was optimized (7 h, n NaBH4/Pd = 10, pH = 9, 170 ℃). • The catalyst Pd/CNTs-D170 has the larger ECSA was attribute to smaller particle. • The Pd/CNTs-D170 shows higher electrocatalytic performance for formic acid. It remains a major challenge to enhance the activity of Pd catalyst and meanwhile minimize the CO poisoning due to adsorbed CO during formic acid oxidation (FAO). Herein, highly dispersed Pd on multi-walled carbon nanotubes (MWCNTs) supported catalysts were prepared in a non-aqueous deep eutectic solvent (DES) system. The catalyst prepared at 170 °C (referred to Pd/CNTs-D170) showed higher catalytic performance toward FAO (peak current: 1712.6 mA mg Pd −1) and better CO anti-poisoning capability (onset potential: 0.59 V, peak potential: 0.69 V) than the Pd/CNTs-W (synthesized in water) (1130.9 mA mg Pd −1, 0.65 V, 0.71 V) and commercial Pd/C (555.8 mA mg Pd −1, 0.66 V, 0.74 V) catalysts. This study provides a suitable strategy for the preparation of high-performance Pd-based electrocatalysts for direct formic acid fuel cell (DFAFC). [ABSTRACT FROM AUTHOR]