Promoting Surface Reconstruction of NiFe Layered Double Hydroxide for Enhanced Oxygen Evolution

Abstract

A dynamic surface reconstruction of oxide electrocatalysts in alkaline media is widely observed especially for layered double hydroxide (LDH), but little is known about how to promote the reconstruction toward desired surfaces for improved oxygen evolution reaction (OER). Here, surface reconstruction of NiFe LDH nanosheets is successfully induced to a higher degree via in situ sulfur doping than that by natural electrochemical activation. Theoretical calculations, operando Raman, and various ex situ characterizations reveal the S anion‐induced effect can lower the energy barrier and facilitate the phase transformation into highly active S‐doped oxyhydroxides. The generated S‐NixFeyOOH can optimize the intermediate adsorption and facilitate the OER kinetics. The reconstructed S‐oxyhydroxides catalyst presents superior OER activity and long‐term durability compared to undoped ones. This work provides a structure–composition–activity relationship during the in situ surface restructuring of NiFe LDH pre‐catalysts.

Pt‐Quantum‐Dot‐Modified Sulfur‐Doped NiFe Layered Double Hydroxide for High‐Current‐Density Alkaline Water Splitting at Industrial Temperature

“…The generated S–Ni x Fe y OOH can optimize the intermediate adsorption and facilitate the reaction kinetics during the OER process. [ 39,40 ] Notably, the catalytic performances of S–NiFe LDH and Pt@S–NiFe LDH are comparable, indicating that Pt nanodots did not enhance OER catalysis. The Ir@S–NiFe LDH exhibits poor catalytic activity compared to the initial S–NiFe LDH (Figure S9b, Supporting Information), suggesting that this deposition method cannot be extended to Ir.…”

Construction of a S and Fe co-regulated metal Ni electrocatalyst for efficient alkaline overall water splitting

“…Moreover, S and Fe atoms reduce the H adsorption energy on the S–Fe–Ni surface. For the OER process, S-doped NiFe hydroxyl oxide converted from the S–Fe–Ni catalyst has strong OH − adsorption, 72 and the in situ formed interface of S–Fe–Ni and derived NiFe hydroxyl oxide could facilitate the deprotonation of *OH and stabilize the *OOH intermediate, thus enhancing alkaline OER performance.…”

Corrosion engineering approach to rapidly prepare Ni(Fe)OOH/Ni(Fe)Sx nanosheet arrays for efficient water oxidation

“…S38a†), which corresponded to the M–O bending and stretching vibrations of M III –OOH (M: Ni, Fe). 42,50,51 This indicates that Ni–OH is transformed into NiOOH at an applied potential of 1.4 V vs. RHE and above. In the specific polarization potential interval (1.45 V to 1.6 V), O 2 bubbles appeared on the surface of Ni(Fe)OOH/Ni(Fe)S x , and the vibrational bands of Raman spectra did not show significant shifts, demonstrating that the M–OOH evolved at the applied potential of 1.4 V vs. RHE is the active phase for catalytic O 2 evolution.…”