Deciphering the structure evolution and active origin for electrochemical oxygen evolution over Ni3S2

“…Figure 4b shows the total density of states (DOS) of NiCuOOH and Cu/NiCuOOH, with both catalysts exhibiting metallic properties due to their non-zero density at Fermi energy, and Cu/NiCuOOH displaying more electron filling at the Fermi level than NiCuOOH, indicating better conductivity [43,44]. In addition, we also calculated the Gibbs free energy of NiCuOOH and Cu/NiCuOOH during the OER reaction, which contains three typical oxygen-containing intermediates (*OH, *O, and *OOH), with Ni being the active site [45,46]. As shown in Figure 4c, the rate determination step (RDS) on NiCuOOH is the first step (from H 2 O to *OH) with an overpotential of 2.24 V. After the introduction of Cu nanoparticles, the RDS of the OER reaction is still the first step from H 2 O to *OH, but its overpotential is significantly reduced to 1.97 V (Figure 4d).…”

Section: Resultsmentioning

confidence: 99%

Engineering Cu/NiCu LDH Heterostructure Nanosheet Arrays for Highly-Efficient Water Oxidation

Wang¹,

Zhang²,

Xu³

et al. 2023

Materials

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The development of stable and efficient electrocatalysts for oxygen evolution reaction is of great significance for electro-catalytic water splitting. Bimetallic layered double hydroxides (LDHs) are promising OER catalysts, in which NiCu LDH has excellent stability compared with the most robust NiFe LDH, but the OER activity is not satisfactory. Here, we designed a NiCu LDH heterostructure electrocatalyst (Cu/NiCu LDH) modified by Cu nanoparticles which has excellent activity and stability. The Cu/NiCu LDH electrocatalyst only needs a low over-potential of 206 mV and a low Tafel slope of 86.9 mV dec−1 at a current density of 10 mA cm−2 and maintains for 70 h at a high current density of 100 mA cm–2 in 1M KOH. X-ray photoelectron spectroscopy (XPS) showed that there was a strong electronic interaction between Cu nanoparticles and NiCu LDH. Density functional theory (DFT) calculations show that the electronic coupling between Cu nanoparticles and NiCu LDH can effectively improve the intrinsic OER activity by optimizing the conductivity and the adsorption energy of oxygen-containing intermediates.

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Section: Origin Of Anions Adsorbed On the Reconstructed Catalystsmentioning

confidence: 99%

mentioning

confidence: 99%

Progress in Manipulating Dynamic Surface Reconstruction via Anion Modulation for Electrocatalytic Water Oxidation

Ajmal

Zhang

et al. 2023

Advanced Science

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The development of efficient and economical electrocatalysts for oxygen evolution reaction (OER) is of paramount importance for the sustainable production of renewable fuels and energy storage systems; however, the sluggish OER kinetics involving multistep four proton‐coupled electron transfer hampers progress in these systems. Fortunately, surface reconstruction offers promising potential to improve OER catalyst design. Anion modulation plays a crucial role in controlling the extent of surface reconstruction and positively persuading the reconstructed species' performances. This review starts by providing a general explanation of how various types of anions can trigger dynamic surface reconstruction and create different combinations with pre‐catalysts. Next, the influences of anion modulation on manipulating the surface dynamic reconstruction process are discussed based on the in situ advanced characterization techniques. Furthermore, various effects of survived anionic groups in reconstructed species on water oxidation activity are further discussed. Finally, the challenges and prospects for the future development directions of anion modulation for redirecting dynamic surface reconstruction to construct highly efficient and practical catalysts for water oxidation are proposed.

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Deciphering the structure evolution and active origin for electrochemical oxygen evolution over Ni3S2

Cited by 17 publications

References 47 publications

Electronic structure modification of ultrathin MnFeOOH and integration with Ni₃S₂ as bifunctional electrocatalysts for improved alkaline water splitting

Electronic structure modification of ultrathin MnFeOOH and integration with Ni₃S₂ as bifunctional electrocatalysts for improved alkaline water splitting

Engineering Cu/NiCu LDH Heterostructure Nanosheet Arrays for Highly-Efficient Water Oxidation

Progress in Manipulating Dynamic Surface Reconstruction via Anion Modulation for Electrocatalytic Water Oxidation

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Deciphering the structure evolution and active origin for electrochemical oxygen evolution over Ni3S2

Cited by 17 publications

References 47 publications

Electronic structure modification of ultrathin MnFeOOH and integration with Ni3S2 as bifunctional electrocatalysts for improved alkaline water splitting

Electronic structure modification of ultrathin MnFeOOH and integration with Ni3S2 as bifunctional electrocatalysts for improved alkaline water splitting

Engineering Cu/NiCu LDH Heterostructure Nanosheet Arrays for Highly-Efficient Water Oxidation

Progress in Manipulating Dynamic Surface Reconstruction via Anion Modulation for Electrocatalytic Water Oxidation

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Electronic structure modification of ultrathin MnFeOOH and integration with Ni₃S₂ as bifunctional electrocatalysts for improved alkaline water splitting

Electronic structure modification of ultrathin MnFeOOH and integration with Ni₃S₂ as bifunctional electrocatalysts for improved alkaline water splitting