Ce-Doped FeNi-Layered Double Hydroxide Nanosheets Grown on an Open-Framework Nickel Phosphate Nanorod Array for Oxygen Evolution Reaction

Abstract

The doping of foreign atoms into the electrocatalyst can effectively adjust the electronic structure and further improve the electrocatalytic activity. Here, we constructed a threedimensional integrated electrode of Ce-doped FeNi LDH (LDH, layered double hydroxide) with an amorphous structure on a Ni foam-supported open-framework nickel phosphate nanorods array (donated as CFN@VSB-5/NF) via a hydrothermal-electrodeposition two-step process. The as-constructed CFN@VSB-5/ NF electrocatalyst merely required an overpotential of 226 mV to generate a current density of 100 mA cm −2 with a Tafel slope of 43.1 mV dec −1 , which was remarkably lower than FN@VSB-5/NF (η 100 = 273 mV) without the addition of Ce. Also, the CFN@VSB-5/NF could continuously catalyze for 50 h at a current density of 500 mA cm −2 without obvious potential fluctuation, presenting appealing durability at a large current density. Further investigations revealed that the superior oxygen evolution reaction (OER) electrocatalytic performance should be attributed to the high intrinsic activity, optimal surface, and electronic structure of the as-constructed CFN@VSB-5/NF catalyst. Compared with the traditional FeNi-based catalysts, moreover, the present CFN@VSB-5/NF-integrated electrocatalyst also displayed stronger OER electrocatalytic activity and excellent stability at large current densities. Markedly, this work provides a path for constructing non-noble metal electrocatalysts with high OER activity.

Boosting of overall water splitting activity by regulating the electron distribution over the active sites of Ce doped NiCo–LDH and atomic level understanding of the catalyst by DFT study

“…2 Among the various methods, the photoelectrochemical water splitting mainly depends on the intensity of light incident on the photoelectrodes resulting in a low current density and hydrolysis of metal hydride leading to the release of a large amount of heat. 3,4 Hence, water electrolysis is considered a suitable route for the production of hydrogen with no carbonaceous emission. This process has a signicant advantage when compared to other methods, with hydrogen used in fuel cells generating water as a by-product with no emission of carbon material.…”

Ce Hydroxide-Interfaced NiFe Sulfide Electrocatalyst with Improved Performance for the Oxygen Evolution Reaction

“…Figure 4c displays the high-resolution spectrum of Ce 3d; the peak located at 916 eV is assigned to the characteristic peak of Ce 4+ , while other peaks demonstrate the coexistence of Ce 3+ and Ce 4+ . 42,43 In addition, the XPS spectra of S 2p in Figure 4d show peaks with binding energies of 162.1 and 163.4 eV, corresponding to the S 2− 2p 3/2 and S 2− 2p 1/2 species, respectively, which indicates metal−sulfur bonds in Ce-(OH) 3 @Fe-Ni 3 S 2 . The binding energy of 168.7 eV corresponds to the oxidized sulfur species, which is from the surface oxidation of sulfur by exposure to air for Ce(OH) 3 @Fe-Ni 3 S 2 .…”

Modulating the Surface Electronic Structure of Active Ni Sites by Engineering Hierarchical NiFe-LDH/CuS over Cu Foam as an Efficient Electrocatalyst for Water Splitting

“…Out of various non-renewable energy resources, hydrogen is considered as a one of the most effective alternative energy sources due to zero emission of CO 2 and its high energy density . There are numerous methods available to produce hydrogen in industries such as coal gasification, partial oxidation of hydrocarbons, steam reforming, hydrolysis of metal hydride, water electrolysis, and photoelectrochemical water splitting. , Among the several methods as mentioned above, water electrolysis could offer a suitable route for hydrogen production with zero emission of carbonaceous by-products.…”