[en] Highlights: • Pd–P/OCNTs using NaH₂PO₂ as the P source and reducing agent was developed. • P and Pd were anchored through the electrostatic interaction and chemical bonds. • Pd NPs could be effectively incorporated with P species (P⁰ or P^V). • P can feasibly change the outer electron structure of the Pd NPs. • Pd–P/OCNTs showed enhanced the electrocatalytic performance for FAO. In the present work, O–functionalized carbon nanotubes (OCNTs) supported Pd–P nanoparticles (Pd–P/OCNTs) were prepared by using sodium hypophosphite (NaH₂PO₂) as the P source and the reducing agent. The presence of O-functionalities on the carbon surface provide a microenvironment of the reaction system which favors the anchorage of P precursors and Pd salt ions through the electrostatic interaction and the formation of chemical bonds on the carbon support. Thus, Pd nanoparticles supported on the OCNTs could be efficiently incorporated with P. Pd with the modified outer electron structure enhanced the electrocatalytic performance for formic acid oxidation (FAO).