Synthesis of polyhedral Pt-Pd-Ni nanobelts regulated by W(CO)6 and applied as a highly performing oxygen reduction reaction electrocatalyst

Pt-Pd-Ni polyhedral nanobelt (PNBs) composite catalysts are synthesized in presence of tungsten hexacarbonyl [W(CO)(6)] by a simple solvothermal method, combining both higher specific surface area and more index active site than the corresponding single-structure catalysts. The thermal decomposition of W(CO)(6) plays a crucial role in the morphology formation. The tenuous composite with a moderate nanobelt width of 7.46 nm formed after heating for 6 h (Pt-Pd-Ni PNBs2) shows better ORR performance and durability than the ternary (Pt-Pd-Ni) and binary (Pt-Pd) single structures. It exhibits a mass activity of 1.49 (A mg(Pt)(-1)), which only degrades by about 10.63 % after 50,000 durability cycles. The metal regulatory effects induced by the carbonyl compounds cause the contraction of the Pt-Pt bonds. Density functional theory calculations indicate that the compressive strain of PtPd-Ni PNBs2 leads to a decrease in the d-band center and overpotential negatively shifted, thus provide a more sufficient and faster ORR proceeding process in thermodynamics, facilitating a higher energy conversion efficiency.