Rational design of NiFe LDH@Ni₃N nano/microsheet arrays as a bifunctional electrocatalyst for overall water splitting

Abstract

Low-cost, efficient and stable electrocatalysts are required for large-scale production of hydrogen by industrial scale water electrolysis. We report here a hybrid bifunctional electrocatalyst, composed of amorphous NiFe LDH nanosheets...

Layered double hydroxide-based electrocatalysts for the oxygen evolution reaction: identification and tailoring of active sites, and superaerophobic nanoarray electrode assembly

“…Pang et al studied both the bubble and electrolyte droplet contact angle on bare NF and NiFe-LDH@Ni 3 N-NF. 199 As shown in Fig. 20b, the NF exhibited both hydrophobicity and aerophobicity (CA 4 1201), while NiFe-LDH@Ni 3 N-NF showed superhydrophilicity (01) and superaerophobicity (153.61).…”

“…Reproduced with permission. 199 Copyright 2020, The Royal Society of Chemistry. (c) Adhesive behaviour of a gas bubble on a (Ni 0.33 Fe 0.67 ) 2 P electrode; inset: the bubble contact angle (E1581 AE 1.21) suggests a negligible interaction between the electrode and gas bubble.…”

Vanadium-Doping and Interface Engineering for Synergistically Enhanced Electrochemical Overall Water Splitting and Urea Electrolysis

“…Meanwhile, the strong hydrogen binding energy (HBE) of Ni leads to the reduced efficiency of hydrogen evolution . To expedite the water dissociation, the integration of Ni 3 N with the promoters of water dissociation such as Ni, Nb 2 O 5 , MoO 2 , and NiFe LDH, is an effective method. To optimize the HBE, the electronic structures and d-band center of catalysts need to be tuned by high-valent metal doping (e.g., V, Cr, Mo, and W), , interface engineering, and defect engineering. , With delicate design, some catalysts such as Ni 3 N-VN, Cr-Co 4 N, Mo-Ni/NiO, and Cr-Ni 3 N/Ni, were capable of adjusting the water adsorption energy and the HBE simultaneously.…”

Recent Progress on Transition Metal Based Layered Double Hydroxides Tailored for Oxygen Electrode Reactions

“…Recently, metal hydroxides or oxides are selected as water cleavage "promoters" for cleaving HO-H bonds to produce hydrogen species to increase the alkaline HER activity [237]. As an example, Wang et al designed and fabricated a bifunctional electrocatalyst, 3D hierarchical heterostructure NiFe-LDHs@Ni 3 N nano/microsheet arrays on Ni foam (NiFe-LDHs@Ni 3 N/NF), showing a low cell voltage of 1.80 V at a current density of 500 mA cm −2 with a remarkable durability of 100 h in an alkaline aqueous electrolyzer [238]. Such bifunctional OER/HER performance was ascribed to the strong coupling and synergistic effects between the NiFe-LDHs nanosheets and the Ni 3 N micro-sheet arrays, which provides a robust integrated structure and fast electron transfer.…”