Highly Active Lanthanum Perovskite Electrocatalysts (LaMnxCo1-xO3 (0 ≤ x ≤ 1)) by Tuning the Mn:Co Ratio for ORR and MOR in Alkaline Medium

• Published in: Electrocatalysis Vol. 14; no. 1; pp. 55 - 67
• Main Authors: Shafath, Sadiyah, Logade, Khulood, Ashok, Anchu, Kumar, Anand, Abu-Reesh, Ibrahim M.
• Format: Journal Article
• Language: English
• Published: New York Springer US 2023; Springer Nature B.V
• Subjects: Catalysis; Catalysts; Chemical reduction; Chemistry; Chemistry and Materials Science; Combustion synthesis; Electrocatalysts; Electrochemistry; Energy Systems; Lanthanum; Original Research; Oxidation; Oxygen evolution reactions; Oxygen reduction reactions; Perovskites; Physical Chemistry; Surface properties; Surface stability; Temperature profiles; Voltammetry; X ray photoelectron spectroscopy; Solution combustion synthesis; Oxygen evolution reaction; Lanthanum perovskites; Electrocatalysts; Oxygen reduction reaction; Methanol oxidation
• ISSN: 1868-2529; 1868-5994
• DOI: 10.1007/s12678-022-00772-0

Lanthanum-based perovskites (LaMn
x
Co
1-
x
O
3
(0 ≤ 
x
 ≤ 1)) were synthesized using a solution combustion synthesis technique with variable ratios of Co and Mn to investigate the surface property and electrocatalytic characteristics (stability and activity of catalyst) for methanol oxidation reaction (MOR), oxygen reduction reaction (ORR), and oxygen evolution reaction (OER) under alkaline medium (KOH). The structural, chemical, and morphological characterizations of the synthesized catalyst were performed by XRD, FTIR, SEM, TEM, and XPS techniques as a function of the Mn:Co elemental ratio. The time–temperature profile during the combustion process was also monitored to study the completion of the combustion reaction and to understand its impact on the structure of the perovskites. SEM/EDX and XPS analysis confirmed the formation of the targeted ratio of Mn and Co on the catalyst. Cyclic voltammetry (CV) and linear sweep voltammetry (LSV) results revealed that all perovskite samples with different Co:Mn ratios were active for ORR, OER, and MOR. The LaMn
x
Co
1-
x
O
3
perovskite with
x
 = 0.4 showed the highest current density compared to the other samples toward all the electrocatalytic reactions under alkaline reaction conditions.
Graphical Abstract