New Phosphorus‐Doped Perovskite Oxide as an Oxygen Reduction Reaction Electrocatalyst in an Alkaline Solution

Abstract

Because of their structural and compositional flexibility, perovskite oxides represent an attractive alternative electrocatalyst class to precious metals for the oxygen reduction reaction (ORR); an important reaction in fuel cells and metal-air batteries. Partial replacement of the original metal cation with another cation, namely, doping, can be used to tailor the ORR activity of perovskite, for which a metal has been exclusively used as the dopant component in the past. Herein, phosphorus is proposed as a non-metal dopant for the cation site to develop a new perovskite family with the formula of La Sr Mn P O (x=0, 0.02, 0.05, and 0.1; denoted as LSM, LSMP0.02, LSMP0.05, and LSMP0.1, respectively). Powder XRD patterns reveal that the solubility of phosphorus in the perovskite structure is around 0.05. Rotating ring-disk electrode experiments in the form of linear-sweep voltammetry scans demonstrated the best ORR performance for LSMP0.05, and also revealed close to a four-electron ORR pathway for all four compositions. A chronoamperometric test (9000 s) and 500 cycle accelerated durability test demonstrated higher durability for LSMP0.05 relative to that of LSM and the commercial 20 wt % Pt/C catalyst. The higher ORR activity for LSMP0.05 is attributed to the optimised average valence of Mn, as evidenced by combined X-ray photoelectron spectroscopy and soft X-ray absorption spectroscopy data. Doping phosphorus into perovskites is an effective way to develop high-performance electrocatalysts for ORR.

Perovskite Oxides for Cathodic Electrocatalysis of Energy‐Related Gases: From O2 to CO2 and N2

“…With the optimized e g ‐filling and increaed oxygen vacancy, LaFeO 3− δ ‐P yielded improved ORR activity. [ 79,80 ]…”

Synthesis of Self‐Ordered Tantalum‐Niobium Mixed Oxide Nanotubes and Their Use for Clean Hydrogen Production

“…Vertically‐oriented nanotubular structures have gained a lot of interest nowadays due to their diverse technological applications [1–6] . The unique structure of the nanotubes ensures excellent carrier transport with low recombination rates while enjoying a high surface‐to‐volume ratio.…”

“…Furthermore, the O 1s spectra (Figure 2d), revealing a singlet peak at 531.2 fitted into two main peaks at 531.6 and 532.4 eV, respectively. The first peak at 531.6 eV characteristic of oxygen ions in the metal oxide lattice, and the second peak at 532.4 eV can be related to the O−H bonding [6,36–38] …”

Supramolecular Iron Complex Formed Between Nitrogen Riched Phenanthroline Derivative and Iron With Improved Oxygen Reduction Activity in Alkaline Electrolyte

“…With the emergence, development and application of anion exchange membranes, the advantages of alkaline fuel cells are become increasingly prominent, and the research of alkaline fuel cells is becoming more and more prosperous both in extension and in-depth. Oxygen reduction reaction is an important parts of alkaline fuel cell, and its reaction kinetics is sluggish than that of hydrogen oxidation (Lefevre et al, 2009; Wang et al, 2012; Shen et al, 2018). Therefore, selecting and developing suitable catalyst for cathodic oxygen reduction reaction is the key to improve the performance of alkaline fuel cell and promote the large-scale use of fuel cell (Chen et al, 2018).…”