Coral-Like LaNi_xFe_1−xO₃ Perovskite Catalyst for High-Performance Oxygen Evolution Reaction

Abstract

With the rare earth element La was selected as the A site and transition metal ions (Ni, Fe) as the B site of perovskite-type oxides with general formula ABO3, a series of LaNixFe1-xO3 (x=0, 0.3, 0.5, 0.7, 0.8, 1.0) perovskite catalysts were prepared by sol-gel method to investigate their catalytic performance for oxygen evolution reaction (OER). The catalyst activity was screened by linear scanning cyclic voltammetry (LSV), Tafel curves, and electrochemical impedance spectroscopy (EIS). A group of electrochemical tests for LaNixFe1-xO3 with various Ni/Fe ratios indicate that LaNi0.8Fe0.2O3 catalyst exhibits excellent electrochemical activity, with a resistance to charge-transfer reaction (Rct) of 5.942 Ω cm-2, overpotential of 391 mV, a Tafel slope of 102.8 mV dec-1, and electrochemical double-layer capacitance (Cdl) of 12.31 mF cm-1. The stability test after 15000 s proves that the optimized LaNi0.8Fe0.2O3 has better stability compared to pristine LaFeO3 and LaNiO3. In addition, LaNi0.8Fe0.2O3 also exhibits the largest electrochemical active area (ECSA=307.75 cm2) and exchange current density (jo=1.08 mA cm-2). This work provides reference for perovskite in improving oxygen evolution performance.

Efficient Visible-Light-Driven Tetracycline Degradation and Cr(VI) Reduction over a LaNi1–xFexO3 (0 ≤ x ≤ 1)/g-C3N4 Type-II Heterojunction Photocatalyst

“…With the increase in the Fe doping content, XRD diffraction peaks shifted to lower diffraction angles. As the ionic radius of Fe 3+ [( r Fe 3+ ) = 0.0645 nm] is larger than that of Ni 3+ [( r Ni 3+ ) = 0.0600 nm], the crystal plane spacing increases, and the crystal structure gradually changes from the trigonal crystal system of LaNiO 3 to the orthorhombic crystal system of LaFeO 3 . , In the case of g-C 3 N 4 , a typical interlayer stacking (002) peak is located at 2θ = 27.7° ( d = 3.28 Å) (JCPDS 87-1526) . As shown in Figures b and S1, weaker g-C 3 N 4 peaks and distinct LaNi 0.8 Fe 0.2 O 3 peaks can be clearly observed in the XRD pattern of L1C1.…”

Facile synthesis of the SnTe/SnSe binary nanocomposite via a hydrothermal route for flexible solid-state supercapacitors

“…The ECSA polarization curve was employed to measure the value of the electrical double-layer capacitance ( C dl ) according to the following eqn (7) . 34 …”

Recent Advances on Perovskite Electrocatalysts for Water Oxidation in Alkaline Medium

“…The influence of the morphology of perovskite on the catalytic performance has always been a hot topic in experimental and theoretical research. ,− Fine control of the micro-/nanostructure engineering of the perovskite morphology can expose abundant active sites and enhance the mass diffusion efficiency, thus improving the catalytic performance of the material. Recently, perovskite catalysts with different morphologies including nanofiber, nanosphere, egg-yolk structure, nanorod, nanotube, porous structure, and nanoparticle have been designed and prepared. ,− For example, Pinxian Xi et al prepared LaCo 1‑x Fe x O 3 perovskite with yolk-shell nanostructure using a ligand-assisted synthesis strategy (Figure a) . Due to its unique structure and composition, the overpotential at 10 mA cm –2 for LaCo 0.75 Fe 0.25 O 3 is only 310 mV (Figure b).…”