High-performance transition metal–doped Pt ₃ Ni octahedra for oxygen reduction reaction

Abstract

Bimetallic platinum-nickel (Pt-Ni) nanostructures represent an emerging class of electrocatalysts for oxygen reduction reaction (ORR) in fuel cells, but practical applications have been limited by catalytic activity and durability. We surface-doped Pt3Ni octahedra supported on carbon with transition metals, termed M-Pt3Ni/C, where M is vanadium, chromium, manganese, iron, cobalt, molybdenum (Mo), tungsten, or rhenium. The Mo-Pt3Ni/C showed the best ORR performance, with a specific activity of 10.3 mA/cm(2) and mass activity of 6.98 A/mg(Pt), which are 81- and 73-fold enhancements compared with the commercial Pt/C catalyst (0.127 mA/cm(2) and 0.096 A/mg(Pt)). Theoretical calculations suggest that Mo prefers subsurface positions near the particle edges in vacuum and surface vertex/edge sites in oxidizing conditions, where it enhances both the performance and the stability of the Pt3Ni catalyst.

Towards Versatile and Sustainable Hydrogen Production through Electrocatalytic Water Splitting: Electrolyte Engineering

“…In general, the anode is in the form of an oxide or hydroxide, and in most cases, it is inactive towards the dissociation of hydrogen molecules. However, the cathode material is also active for the ORR in most cases, for example, Pt171, 172, 173 and multi‐metal electrodes,174, 175, 176, 177, 178, 179 as is known for fuel cell technology. Thus, oxygen‐tolerant cathodes are highly desirable 180.…”

Charge distribution and Fermi level in bimetallic nanoparticles

“…In recent years, bimetallic nanoparticles have received increasing attention due to their promising electrocatalytic, [1][2][3] catalytic, [4][5][6][7][8] magnetic, 4,9,10 and optical properties. 4,11 The interaction of nanoparticles with their environment can, sometimes drastically, shift the Fermi level of electrons in the nanoparticles, influencing their chemical and electrochemical properties, as highlighted in a recent review.…”

Potential‐Cycling Synthesis of Single Platinum Atoms for Efficient Hydrogen Evolution in Neutral Media

“…This result is consistent with the X‐ray diffraction (XRD) pattern of a centimeter‐scale piece of PtSA‐NT‐NF (Figure 3 a), which contains the signals of not Pt but Ni(OH) 2 , CoP, and Co 2 P crystal grains. Moreover, as shown in Figure 3 b, the X‐ray photoelectron spectrum (XPS) of commercial Pt/C containing Pt nanoparticles displays two Pt 4f peaks at 71.6 and 74.9 eV, indicative of Pt 0 (Refs 4b, 13c, 19). In contrast, the two Pt 4f peaks of a centimeter‐scale piece of PtSA‐NT‐NF are located at 72.3 and 75.6 eV, which are characteristic of Pt 2+ (Refs.…”

“…In contrast, the two Pt 4f peaks of a centimeter‐scale piece of PtSA‐NT‐NF are located at 72.3 and 75.6 eV, which are characteristic of Pt 2+ (Refs. 4b, 13c, 19). The lack of a detectable Pt 0 signal implies that not Pt crystal grains but only single Pt atoms exist in PtSA‐NT‐NF, conforming to the absence of Pt crystal grain signals in the XRD and the electron diffraction patterns.…”