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选择性和持久的H₂O₂电合成催化剂在酸中通过化诱导的应力和分相

Zhiyong Yu¹, Hao Deng^2,3,4, Qing Yao¹

¹State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China.

Nature communications

|October 30, 2024

概括

在芯上开发无形-外使得在酸性条件下高效的过氧化 (H2O2) 电合成成为可能. 这种新型催化剂对H2O2的生产和降解具有很高的选择性和稳定性.

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
催化剂是一种催化剂.

背景情况:

酸性过氧化 (H2O2) 电合成的电催化剂在选择性和稳定性方面面临挑战.
优化氧降解反应 (ORR) 途径对于高效的H2O2生产至关重要.

研究的目的:

在酸性介质中开发高效稳定的电催化剂,用于H2O2电合成.
研究 (Pt) 芯上的无形- (Pt-Se) 外在操纵ORR路径中的作用.

主要方法:

在晶体Pt核上构建无形Pt-Se外.
使用纳米颗粒具有优化的外厚度用于H2O2生产.
在流电池反应堆中测试催化剂性能,以测量H2O2度和生产率.
评估催化剂在有机染料降解中的有效性.

主要成果:

在Pt核心上的Pt-Se外实现了超过95%的H2O2生产选择性,抑制了分解.
催化剂在400小时内保持了250 mA cm-2的电流密度.
达到113.2g L−1的H2O2度,生产率为4160.3 mmol gcat−1h−1.1.
使用产生的H2O2.2,证明有效的有机染料降解.

结论:

Pt核上的无形Pt-Se外通过优化ORR路径有效催化酸中的H2O2电合成.
Pt-Se外增强了O2吸附和OOH*结合,加速了反应动力学,提高了选择性和稳定性.
化方法可用于调整其他贵金属催化剂中的2e−ORR路径.

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