精确的合成控制独有的联结体效应增强氧降解催化
1School of Materials Science and Engineering, Peking University, Beijing, 100871, China.
Nature communications
|October 29, 2023
概括
这项研究精确合成了-/芯/外纳米板,以隔离氧降解反应中的联体效应. 结果表明增强了活性和稳定性,为催化剂设计提供了新的见解.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 纳米技术纳米技术
背景情况:
- 理论上说,联体效应通过改变d波段中心来增强催化氧降解反应 (ORR).
- 在真正的纳米结构中,联体效应经常被应变效应混,掩盖了它对电催化活动的唯一贡献.
- 实验验证隔离联结体效应对ORR的影响仍然是一个挑战.
研究的目的:
- 为了合成核心/外纳米结构,这些纳米结构表现出氧降解反应的专属连接体效应.
- 通过实验确定联结效应对电催化活性改善的贡献,独立于应变效应.
- 调查电子结构的变化及其与ORR性能增强的相关性.
主要方法:
- 精确合成Pd3Ru1/Pt核心/外纳米板与匹配的格子参数,以消除应变.
- 在Pd3Ru1核心上,金覆盖层逐层生长.
- 合成的纳米板的电化学表征,以测量氧降解反应活性和稳定性,在性和酸性电解质中.
- 分析电子转移和d波段中心转移由于连接体效应.
主要成果:
- 成功合成了没有格子不匹配的Pd3Ru1/Pt核心/外纳米板,确保了孤立的连接体效应.
- 观察到电子从Pd3Ru1转移到Pt,导致Pt d频段中心的下移.
- 最佳的Pd3Ru1/Pt1-2L纳米板在各种电解质中表现出极好的活性和稳定性,用于氧降解反应.
- 证明,仅靠连接物效应就能显著提高电催化性能.
结论:
- 精确的合成策略使得在Pd3Ru1/Pt核心/外纳米结构中隔离联体效应成为可能.
- 通过电子转移和d波段中心修改,隔离的连接体效应显著提高了氧降解反应的性能.
- 这些发现为联结体效应的有益作用提供了关键的实验证据,并为设计高效电催化剂提供了途径.
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