Porous palladium phosphide nanotubes for formic acid electrooxidation

Abstract The development of an efficient catalyst for formic acid electrocatalytic oxidation reaction (FAEOR) is of great significance to accelerate the commercial application of direct formic acid fuel cells (DFAFC). Herein, palladium phosphide (Pd_xP_y) porous nanotubes (PNTs) with different phosphide content (i.e., Pd₃P and Pd₅P₂) are prepared by combining the self‐template reduction method of dimethylglyoxime‐Pd(II) complex nanorods and succedent phosphating treatment. During the reduction process, the self‐removal of the template and the continual inside–outside Ostwald ripening phenomenon are responsible for the generation of the one‐dimensional hollow and porous architecture. On the basis of the unique synthetic procedure and structural advantages, Pd₃P PNTs with optimized phosphide content show outstanding electroactivity and stability for FAEOR. Importantly, the strong electronic effect between Pd and P promotes the direct pathway of FAEOR and inhibits the occurrence of the formic acid decomposition reaction, which effectively enhances the FAEOR electroactivity of Pd₃P PNTs. In view of the facial synthesis, excellent electroactivity, high stability, and unordinary selectivity, Pd₃P PNTs have the potential to be an efficient anode electrocatalyst for DFAFC.