对有序中孔碳支持的Pt基催化剂的氧降解动力学和机制的研究
1Graduate School of Natural and Applied Sciences, Gazi University, Ankara, Turkey.
Turkish journal of chemistry
|December 25, 2023
概括
这项研究研究了氧降解反应 (ORR) 催化剂. 经过修改的 mesoporous carbon (OMC) 支持的 (Pt) 催化剂显示出增强的电活性和占主导地位的 4 电子水形成路径.
科学领域:
- 电化学 电化学 电化学
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
背景情况:
- 氧降解反应 (ORR) 对能量转换装置至关重要.
- 开发高效和耐用的ORR催化剂对于推进燃料电池技术至关重要.
- 订制的半孔碳 (OMC) 提供了一个有前途的支材料,由于其高表面积和可调节性质.
研究的目的:
- 调查ORR在Pt和PtAgFe催化剂上的动力学和机制,这些催化剂由有序半孔碳 (OMC) 支持.
- 评估OMC表面修改对催化剂性能的影响.
- 为了比较OMC支持的催化剂与商业Pt/C催化剂的性能.
主要方法:
- 在表面修改和未修改的OMC上使用湿浸-减少合成Pt和PtAgFe催化剂.
- 使用循环电量计 (CV) 和旋转盘电极 (RDE) 技术进行电化学表征.
- 分析电活性表面积,质量活动和电子转移数.
主要成果:
- 在修改后的OMC (Pt/OMC-M) 上支持的Pt表现出最高的电活性表面积 (987 cm2/mg) 和质量活性 (39.1 mA/mgPt).
- 支持OMC的Pt和PtAgFe催化剂主要遵循4电子水形成路径.
- 与未经修改的同行相比,经过修改的OMC支持的催化剂通常表现出更高的氧气减少活动.
- 支持OMC的催化剂的ORR机制类似于Pt/C,具有更明显的关联途径.
结论:
- 对OMC的表面修改显著提高了ORR支持的Pt催化剂的电催化活性.
- 支持OMC的催化剂与商业Pt/C具有竞争力,为提高燃料电池性能提供了潜力.
- 主要的4电子通路和关联机制表明ORR过程中能有效地产生水.
相关概念视频
02:50Catalysis
27.0K
The presence of a catalyst affects the rate of a chemical reaction. A catalyst is a substance that can increase the reaction rate without being consumed during the process. A basic comprehension of a catalysts’ role during chemical reactions can be understood from the concept of reaction mechanisms and energy diagrams.
27.0K
02:13Reduction of Alkenes: Catalytic Hydrogenation
12.0K
Alkenes undergo reduction by the addition of molecular hydrogen to give alkanes. Because the process generally occurs in the presence of a transition-metal catalyst, the reaction is called catalytic hydrogenation.
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
12.0K
02:24Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
7.7K
Introduction
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
7.7K
02:44Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
10.2K
Alkenes are converted to 1,2-diols or glycols through a process called dihydroxylation. It involves the addition of two hydroxyl groups across the double bond with two different stereochemical approaches, namely anti and syn. Dihydroxylation using osmium tetroxide progresses with syn stereochemistry.
10.2K