| 1. |
- Han, Ning, et al.
(författare)
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Lowering the kinetic barrier via enhancing electrophilicity of surface oxygen to boost acidic oxygen evolution reaction
- 2024
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Ingår i: Matter. - 2590-2393 .- 2590-2385. ; 7:3, s. 1330-1343
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Tidskriftsartikel (refereegranskat)abstract
- The acidic oxygen evolution reaction (OER) is essential for many renewable energy conversion and storage technologies. However, the high energy required to break the strong covalent O-H bond of H2O in acidic media results in sluggish OER kinetics. Here, we report the critical role of iron in a new family of iron-containing yttrium ruthenate (Y2-xFexRu2O7-δ) electrocatalysts in highly increasing the electrophilicity of surface oxygen, leading to a significant reduction of the kinetics barrier by 33%, thus an exceptional OER mass activity of 1,021 A· up to 12.4 and 7.7 times that of Y2Ru2O7-δ and RuO2, respectively. Introducing iron reduces the Mulliken atomic charge on the O sites in the generated Ru-O-Fe structure, thereby facilitating the acid-base nucleophilic assault from H2O and reducing the free energy on the rate-determining step of OER. This work provides an effective strategy to reduce the kinetics barrier to achieve highly efficient and economic OER in acidic conditions.
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| 2. |
- Pang, Kanglei, 1993-, et al.
(författare)
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Redirecting configuration of atomically dispersed selenium catalytic sites for efficient hydrazine oxidation
- 2024
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Ingår i: Matter. - 2590-2393 .- 2590-2385. ; 7:2, s. 655-667
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Tidskriftsartikel (refereegranskat)abstract
- Understanding the reconstruction of surface sites is crucial for gaining insights into the true active sites and catalytic mechanisms. While extensive research has been conducted on reconstruction behaviors of atomically dispersed metallic catalytic sites, limited attention has been paid to non-metallic ones despite their potential catalytic activity comparable or even superior to their noble-metal counterpart. Herein, we report a carbonaceous, atomically dispersed non-metallic selenium catalyst that displayed exceptional catalytic activity in the hydrazine oxidation reaction (HzOR) in alkaline media, outperforming the noble-metal Pt catalysts. In situ X-ray absorption spectroscopy (XAS) and Fourier transform infrared spectroscopy revealed that the pristine SeC4 site pre-adsorbs an ∗OH ligand, followed by HzOR occurring on the other side of the OH–SeC4. Theoretical calculations proposed that the pre-adsorbed ∗OH group pulls electrons from the Se site, resulting in a more positively charged Se and a higher polarity of Se–C bonds, thereby enhancing surface reactivity toward HzO/R.
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