A-Site Cation-Ordering Layered Perovskite EuBa_0.5Sr_0.5Co_2–xFe_xO_5+δ as Highly Active and Durable Electrocatalysts for Oxygen Evolution Reaction

Abstract

The developments of high-performance and tolerant catalysts may enable more sustainable energy in the future, especially toward water oxidation. Herein, we report A-site cation-ordering layered perovskite EuBa 0.5 Sr 0.5 Co 2−x Fe x O 5+δ (EBSCFx) (x = 0.2−0.6) electrocatalysts. When evaluated for oxygen evolution reaction (OER) in alkaline media, EuBa 0.5 Sr 0.5 Co 1.6 Fe 0.4 O 5+δ (EBSCF0.4) exhibits the best catalytic activity among all of these catalysts, as evidenced by the lowest overpotential of 420 mV at a current density of 10 mA cm −2 . Notably, the catalytic activity of EBSCF0.4 is better than that of commercial IrO 2 at the overpotential >460 mV. Furthermore, the EBSCF0.4−20RuO 2 (involving 20 wt % RuO 2 ) composite catalyst is developed and gives an overpotential as low as 390 mV at 50 mA cm −2 , which is even superior to commercial RuO 2 . For overall water splitting, an electrolysis voltage of merely 1.47 V is achieved at 10 mA cm −2 in an electrolyzer employing EBSCF0.4−20RuO 2 as bifunctional catalysts, with exceptional durability for 24 h. Such a performance outperforms state-of-the-art IrO 2 ∥Pt/C and RuO 2 ∥Pt/C couples. According to density functional theory (DFT) calculations, the unique catalytic properties of EBSCF0.4 may benefit from highly active Fe sites with octahedral coordination, and the synergistic effects of Fe and Ru sites in the composite catalyst accelerate the electrochemical water oxidation.

Iron and Manganese Codoped Cobalt Tungstates Co1–(x+y)FexMnyWO4 as Efficient Photoelectrocatalysts for Oxygen Evolution Reaction

“…Among common methods, the electrochemical and photocatalytic reactions govern many systems such as fuel cells, metal air batteries, and water splitting systems . The main focus of these reactions is oxygen evolution reaction (OER), hydrogen evolution reaction (HER), oxygen reduction reaction (ORR), and photocatalytic water splitting . Visible-light-driven electrochemical water splitting is an outbreak for the production of energy from water.…”

Recent Advances in Perovskite Oxides Electrocatalysts: Ordered Perovskites, Cations Segregation and Exsolution

“…reported a layered perovskite La 2 NiO 4 bifunctional ORR/OER electrocatalyst exhibiting a reduced voltage gap (1.51 V at 75 mA cm −2 ) than Pt/C (1.62 V), as well as high stability for metal‐air batteries. Wang et al [12] . developed an A‐site ordering layered perovskite EuBa 0.5 Sr 0.5 Co 1.6 Fe 0.4 O 5+δ (EBSCF 0.4 ), demonstrating a high OER catalytic activity with an overpotential of 420 mV at 10 mA cm −2 .…”

High-Efficiency of Bi-Functional-Based Perovskite Nanocomposite for Oxygen Evolution and Oxygen Reduction Reaction: An Overview

“…Interestingly, the crystal structure of cobalt-free BaFeO 3−δ (BF) perovskite has become an innovative new class of electrode catalyst, specifically the surface-active cathode materials that play an important role in the development of oxygen-ion conductivity for SOFCs and exhibit a power density value of 870 mW cm −2 [ 60 ]. Wang et al [ 61 ] have developed a high-performance-based A-site cation-layered EuBa 0.5 Sr 0.5 Co 2-x Fe x O 5+δ (EBSCF 0.4 -20RuO 2 ) bifunctional perovskite that can be used as an efficient electrocatalyst for OER and water splitting.…”

“…Interestingly, the crystal structure of cobalt-free BaFeO 3−δ (BF) perovskite has become an innovative new class of electrode catalyst, specifically the surface-active cathode materials that play an important role in the development of oxygen-ion conductivity for SOFCs and exhibit a power density value of 870 mW cm −2 [60]. Wang et al [61] have developed a high-performance-based A-site cation-layered EuBa 0.5 Sr 0.5 Co 2-x Fe x O 5+δ (EBSCF 0.4 -20RuO 2 ) bifunctional perovskite that can be used as an efficient electrocatalyst for OER and water splitting. Interestingly, the crystal structure of cobalt-free BaFeO3-δ (BF) perovskite has become an innovative new class of electrode catalyst, specifically the surface-active cathode materials that play an important role in the development of oxygen-ion conductivity for SOFCs and exhibit a power density value of 870 mW cm −2 [60].…”