Hierarchical Polyelemental Nanoparticles as Bifunctional Catalysts for Oxygen Evolution and Reduction Reactions

Abstract

Efficient electrocatalysts are critical in various clean energy conversion and storage systems.Polyelemental nanomaterials are attractive as multi-functional catalysts due to their wide compositions and synergistic properties. However, controlled synthesis of polyelemental nanomaterials is difficult due to their complex composition. Herein, we present a one-step synthetic strategy to fabricate a hierarchical polyelemental nanomaterial, which contains ultra-small precious metal nanoparticles (IrPt, ~5 nm) anchored on spinel-structure transition metal oxide nanoparticles.The polyelemental nanoparticles serve as excellent bifunctional catalysts for the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). The mass catalytic activity of the polyelemental nanoparticles is 7-times higher than that of Pt in ORR and 28-times that of Ir in OER at the same overpotentials, demonstrating the high activity of the bifunctional electrocatalyst. We attribute this outstanding performance to the controlled multiple elemental composition, mixed chemical states, and large electroactive surface area. The hierarchical nanostructure and polyelemental design of these nanoparticles offers a general and powerful alternative material for catalysis, solar cells, and more.

On the electronic structure and hydrogen evolution reaction activity of platinum group metal-based high-entropy-alloy nanoparticles

“…11 Löffler et al found that Cr-Mn-Fe-Co-Ni complex solid solution showed at least comparable catalytic activity to Pt in oxygen reduction reaction (ORR), in despite that none of its constituents had good ORR activity. 12 In addition to HEA, other alternative denominations have also been discussed elsewhere, such as complex solid solutions, [12][13][14] multiprincipal element alloys, 15 polyelemental particles, 16,17 multi-elemental alloy, 18 and multimetallic clusters/particles. 19 These kinds of alloys may present a class of promising ideal catalysts having desired activity, stability and selectivity and thus make a paradigm shi in catalysis research.…”

“…19 These kinds of alloys may present a class of promising ideal catalysts having desired activity, stability and selectivity and thus make a paradigm shi in catalysis research. 20 These alloy catalysts with appealing performances have been reported recently, [10][11][12][17][18][19][21][22][23][24] yet, the interpretation on their properties is still challenging. Quite recently, Rossmeisl and co-authors have made a great step in theoretically predicting ORR 25 and CO 2 and CO reduction 26 properties on HEAs by combing density functional theory calculations and supervised machine learning.…”

Co-FeS2/CoS2 Heterostructured Nanomaterials for pH Sensing

“…The two peaks with binding energies of 778.7 and 794.1 eV belong to cobalt in Co-FeS 2 . The fitted peaks at 780.9 eV and 797.3 eV can be assigned to cobalt in single-phase CoS 2 [ 25 ]. The two satellite peaks (identified as “Sat”) with binding energies at 784.8 and 803.3 eV are attributed to oxidized Co, produced by the oxidation of the Co-FeS 2 /CoS 2 surface [ 26 ].…”

Interface Engineering of Air Electrocatalysts for Rechargeable Zinc–Air Batteries

“…Catalyst with single component that works to either ORR or OER is generally unsatisfied to the other reaction. [ 86 ] For example, Pt as the efficient ORR catalyst can be oxidized under OER condition, and OER catalyst, such as Ir‐ or Ru‐based catalyst, is insufficient to ORR. Therefore, it is natural to put forward the concept of exploring bifunctional active catalyst from incorporating multiple targeted components, since formation of polyelemental catalyst can combine the merits of different component.…”

“…Reproduced with permission. [ 86 ] Copyright 2019, American Association for the Advancement of Science. e) Schematic illustration of metal atom trapped by defect.…”