Dynamic structural transformation induced by defects in nano-rod FeOOH during electrochemical water splitting

Hu, Yitian; Zhou, Jing; Li, Lili; Hu, Zhiwei; Yuan, Taotao; Jing, Chao; Liu, Renduo; Xi, Shibo; Jiang, Haiqing; Wang, Jianqiang; Zhang, Linjuan

doi:10.1039/d1ta08938b

Cited by 27 publications

(25 citation statements)

References 70 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Raman spectra are shown in Figure b, where the peaks located at 308, 386, 546, 612, and 728 cm –1 are typical Raman vibrational peaks of β-FeOOH. , The relative intensity of the characteristic peaks at 308 and 386 cm –1 can distinguish between β-FeOOH and α-FeOOH. When the peak intensity at 308 cm –1 is higher than that at 386 cm –1 , it indicates that the sample is β-FeOOH . Upon doping with Ni 2+ and Co 2+ and further doping with Yb 3+ , the positions and relative intensities of the Raman characteristic peaks of the catalysts do not change significantly, indicating that FeOOH/CC, Ni,Co–FeOOH/CC, and Ni,Co,Yb–FeOOH/CC are all β-FeOOH, which is consistent with the XRD patterns.…”

Section: Resultssupporting

confidence: 74%

“…When the peak intensity at 308 cm −1 is higher than that at 386 cm −1 , it indicates that the sample is β-FeOOH. 32 The chemical environments and valence states of each element in the catalyst are analyzed by X-ray photoelectron spectroscopy (XPS). Figure 2c is the high-resolution XPS spectra of O 1s, where the peak at the binding energy of 529.62 eV is attributed to M−O, the peak at 531.20 eV corresponds to M−OH, and the peak at 532.46 eV corresponds to the hydroxyl group or water adsorbed on the surface of catalysts.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Ni, Co, and Yb Cation Co-doping and Defect Engineering of FeOOH Nanorods as an Electrocatalyst for the Oxygen Evolution Reaction

et al. 2023

View full text Add to dashboard Cite

Electrocatalytic water splitting is a feasible technology that can produce hydrogen from renewable sources. The oxygen evolution reaction (OER), which has a slower kinetics and higher overpotential than the hydrogen evolution reaction, is the bottleneck that limits the overall water splitting. It is essential to develop efficient OER catalysts to reduce the anode overpotential. Herein, Ni,Co,Yb–FeOOH nanorod arrays grown directly on a carbon cloth are synthesized by a simple one-step hydrothermal method. The doped Ni2+ and Co2+ can occupy Fe2+ and Fe3+ sites in FeOOH, increasing the concentration of oxygen vacancies (V O), and the doped Yb3+ with a larger ionic radius can occupy the interstitial sites, which leads to more edge dislocations. V O and edge dislocations greatly enrich the active sites in FeOOH/CC. In addition, density functional theory calculations confirm that doping of Ni2+, Co2+, and Yb3+ modulates the electronic structure of the main active Fe sites, bringing its d-band center closer to the Fermi level and reducing the Gibbs free energy change of the rate-determining step of the OER. When the current density reaches 10 mA cm–2, the overpotential of Ni,Co,Yb–FeOOH/CC is only 230.9 mV, and the Tafel slope is 22.7 mV dec–1. In particular, a mechanism of multi-cation doping synergistic interaction with the oxygen vacancy and edge dislocation to enhance the OER catalytic activity of the material is proposed.

show abstract

Section: Resultssupporting

confidence: 74%

Section: Resultsmentioning

confidence: 99%

Ni, Co, and Yb Cation Co-doping and Defect Engineering of FeOOH Nanorods as an Electrocatalyst for the Oxygen Evolution Reaction

et al. 2023

View full text Add to dashboard Cite

show abstract

“…[14] In recent years, several studies have begun to focus on the effects and modulation of the reconstruction process and products, such as pH, potential, phase composition, and structural defects. [25][26][27][28][29] However, even if the reconstruction has a huge modulation space, its precise tuning, especially in situ tuning, remains a challenge. In the field of OER, the reconstruction process usually occurs in linear sweep voltammetry (LSV), cyclic voltammetry (CV), or chronopotentiometry (CP) testing, as these techniques are the performance evaluation methods for electrocatalysts.…”

Section: Introductionmentioning

confidence: 99%

Potentiostatic Reconstruction of Nickel‐Cobalt Hydroxysulfate with Self‐Optimized Structure for Enhancing Energy Storage

Yang

Zhang

et al. 2022

Advanced Energy Materials

View full text Add to dashboard Cite

Transition metal chalcogenides (TMCs) are widely used as energy storage materials, however, most studies have neglected the reconstruction process that occurs during the operation. Thus, the intrinsic energy storage mechanism of TMCs and the identification and modulation of the reconstruction process are not adequately investigated. Herein, a proactive modulation strategy for reconstruction kinetics under nonoperating conditions is proposed, and a potentiostatic reconstruction method is developed. The effects of three electrochemical techniques of potentiostatic, cyclic voltammetry, and galvanostatic on reconstruction products are also revealed. Notably, under potentiostatic reconstruction, the needle‐like nickel‐cobalt sulfide precursor is transformed into columnar, polycrystalline, defect‐rich nickel‐cobalt hydroxysulfate (NCHS‐E), and the process is analyzed in detail by in situ and ex situ characterization. NCHS‐E exhibits an excellent electrochemical performance with a specific capacity of 5040 mC cm−2 at 1 mA cm−2 and capacity retention of 67.1% at 50 mA cm−2. Kinetic analysis and theoretical calculations show that NCHS‐E has fast charge transfer ability and low deprotonation energy, indicating a favorable energy storage pathway. This work proves the important potential of reconstruction kinetic modulation to optimize the structure and properties of the products and provides new insights into the mechanism of reconstruction occurrence.

show abstract

“…14 For practical applications, Febased oxyhydroxides have great potential due to their low cost and abundance, especially bimetallic iron oxyhydroxides such as FeNiOOH and FeCoOOH exhibit excellent electrocatalytic properties. 8 Besides, the Fe-based system with its variable oxidation states readily adsorbs OH − species and possesses high intrinsic electrocatalytic activity. 8,15 However, Fe-based catalysts suffer from poor intrinsic conductivity and sluggish oxidation kinetics.…”

Section: ■ Introductionmentioning

confidence: 99%

Tapping the Potential of High-Valent Mo and W Metal Centers for Dynamic Electronic Structures in Multimetallic FeVO(OH)/Ni(OH)₂ for Ultrastable and Efficient Overall Water Splitting

Moi

Sahu

Qureshi

2023

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

Rationally designing a noble metal-free electrocatalyst for OER and HER is pivotal for large-scale energy generation via water splitting. A multimetallic electrocatalyst FeVO(OH)/Ni0.86Mo0.07W0.07(OH)2, aimed at tuning the electronic structure, is fabricated and shows considerable improvement in the water-splitting reaction kinetics, aided by low Tafel slope values of 24 mV/dec for OER and 67 mV/dec for HER, respectively. By taking advantage of (e̅–e̅) repulsions at the t2g level, we introduced high-valency Mo and W to provide a viable path for π-electron donation from oxygen 2p orbitals to vacant Mo and W orbitals for a dynamic electronic structure and an interfacial synergistic effect, which optimized the bond lengths for reaction intermediates to facilitate water splitting. The hybrid catalyst FeVO(OH)/NiMoW(OH)2 shows intrinsic activity and durability toward OER and HER tested for 48 h at a current density of 20 mA/cm2 and a cell voltage of 1.65 V @ 20 mA/cm2.

show abstract

Dynamic structural transformation induced by defects in nano-rod FeOOH during electrochemical water splitting

Abstract: Defect engineering is a prevailing strategy for enhancing the oxygen evolution reaction activity for water spitting of electrocatalysts with a single phase or single metal; however, the exact role of...

Cited by 27 publications

References 70 publications

Ni, Co, and Yb Cation Co-doping and Defect Engineering of FeOOH Nanorods as an Electrocatalyst for the Oxygen Evolution Reaction

Ni, Co, and Yb Cation Co-doping and Defect Engineering of FeOOH Nanorods as an Electrocatalyst for the Oxygen Evolution Reaction

Potentiostatic Reconstruction of Nickel‐Cobalt Hydroxysulfate with Self‐Optimized Structure for Enhancing Energy Storage

Tapping the Potential of High-Valent Mo and W Metal Centers for Dynamic Electronic Structures in Multimetallic FeVO(OH)/Ni(OH)₂ for Ultrastable and Efficient Overall Water Splitting

Contact Info

Product

Resources

About

Dynamic structural transformation induced by defects in nano-rod FeOOH during electrochemical water splitting

Abstract: Defect engineering is a prevailing strategy for enhancing the oxygen evolution reaction activity for water spitting of electrocatalysts with a single phase or single metal; however, the exact role of...

Cited by 27 publications

References 70 publications

Ni, Co, and Yb Cation Co-doping and Defect Engineering of FeOOH Nanorods as an Electrocatalyst for the Oxygen Evolution Reaction

Ni, Co, and Yb Cation Co-doping and Defect Engineering of FeOOH Nanorods as an Electrocatalyst for the Oxygen Evolution Reaction

Potentiostatic Reconstruction of Nickel‐Cobalt Hydroxysulfate with Self‐Optimized Structure for Enhancing Energy Storage

Tapping the Potential of High-Valent Mo and W Metal Centers for Dynamic Electronic Structures in Multimetallic FeVO(OH)/Ni(OH)2 for Ultrastable and Efficient Overall Water Splitting

Contact Info

Product

Resources

About

Tapping the Potential of High-Valent Mo and W Metal Centers for Dynamic Electronic Structures in Multimetallic FeVO(OH)/Ni(OH)₂ for Ultrastable and Efficient Overall Water Splitting