Ce-doping induced structure evolution in FeNi-based (oxy)hydroxide for highly efficient oxygen evolution reaction

Distorted Ge–O–Fe Microstructure as an Active Unit in Hematite to Accelerate Solar Water Splitting

“…A small peak at 2.57 Å can also be observed, which is different from the Ge–O–Ge configuration in GeO 2 but matches the Fe–O–Fe environment as revealed by the Fe K -edge EXAFS curve (red curve in Figure g). The results suggest that the Ge atom has been dispersed in Fe 2 O 3 at the vacancy site instead of the formation of a tiny GeO 2 cluster, in good agreement with the HAADF-STEM results, but it shows a position different from the typical Fe vacancy and exhibits a shorter Ge–O bond length than that of Fe–O, leading to a distored local structure. − …”

1-Butyl-3-methylimidazolium hydrogen sulfate-induced structure modification and reconstruction of nickel foams for oxygen evolution reactions

“…40 The peaks at 552 cm −1 and 478 cm −1 were assigned to the vibrations of Ag( ν (Ni–O)) and Eg( δ (Ni–O)) of γ-NiOOH with a high ration of δ (Ni–O) to ν (Ni–O). 40–43 The peaks for γ-NiOOH increased with the [BMIM]HSO 4 % increasing from 0.6% to 6%. Therefore, the hierarchical layers [BMIM]–SO 4 –Ni@NF were reconstructed to γ-NiOOH on the surface of BM x NF during the OER process.…”

“…17 Ni 2p 3/2 and Ni 2p 1/2 at 855.2 eV and 873.1 eV were assigned to trivalent nickel (Ni 3+ ), indicating the formation of NiOOH. 41–43 The O 1s peak shows contributions from three oxygen environments. One small and broad peak was detected at 532.7 eV from oxygen in the hydroxyl group or surface-adsorbed molecular water.…”

3D nanostructured Ce-doped CoFe-LDH/NF self-supported catalyst for high-performance OER

“…44 Because the ionic radii of La 3+ (0.103 nm) and Ce 3+ (0.101 nm) are larger than that of Fe 3+ (0.065 nm), the partial substitution of Fe 3+ may lead to lattice distortion and more defects in catalysts, thereby enhancing the OER performance. 45–47 Upon Ce 3+ or La 3+ adding to CoFe, the diffraction peaks of the (003) crystal plane shifted to large angles and the interlayer spacings of Ce-CoFe ( d 003 ) and Le-CoFe ( d 003 ) increased to 0.811 nm and 0.794 nm, respectively. Moreover, the strongest peak of the (003) crystal plane of CoFe became a small “hump” in Ce-CoFe and La-CoFe, showing a decline in the crystallinity.…”