4.8 Article

Interstitial carbon atoms enhance both selectivity and activity of rhodium catalysts toward C-C cleavage in direct ethanol fuel cells

期刊

NANO ENERGY
卷 113, 期 -, 页码 -

出版社

ELSEVIER
DOI: 10.1016/j.nanoen.2023.108597

关键词

Interstitial carbon atom; Rhodium catalyst; C -C cleavage; Selectivity; Direct ethanol fuel cells

向作者/读者索取更多资源

Selective breaking of the C-C bond in ethanol is crucial for various industrial processes, and introducing C atoms into the interstitial sites of Rh nanosheets enhances this process. The insertion of C atoms changes the Rh lattice structure and promotes the exothermic cleavage of the C-C bond. Based on these findings, a new method is developed to enhance the selectivity and activity of commercial Rh black catalysts by introducing C atoms into their surface.
Selective breaking of the C-C bond in ethanol holds the key to many industrial processes, including the operation of direct ethanol fuel cells and steam reforming. Interstitial C atoms in the subsurface region of noble-metal catalysts have major impacts on the selectivity and activity, but an understanding of the mechanistic details is still elusive due to their nature of in situ formation and metastability. Herein, we develop a method to obtain stable RhCx (x & AP; 0.5) by introducing C atoms into the interstitial sites of well-defined Rh nanosheets of 8-10 at. layers in thickness, and further elucidate the electronic and geometric effects of the interstitial C atoms on the cleavage of C-C bond. With the introduction of C atoms into half of the octahedral sites, the Rh lattice changes from a cubic to an orthorhombic structure. The lattice expansion induced by the insertion of C atoms, together with the electron transfer between C and Rh atoms, effectively suppresses the coupling reaction between OH* and CH3CO* to form acetic acid while making the cleavage of C-C bond more exothermic. As such, we obtain a selectivity of ethanol to CO2 as high as 18.1 %, much higher than those of the Rh counterpart (10.0 %), together with 3.1-fold improvement in kinetics. Guided by these findings, a new method is also developed to directly introduce C atoms into the subsurface of a commercial Rh black to enhance its selectivity and activity by 2.5- and 1.6- folds, respectively.

作者

我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。

评论

主要评分

4.8
评分不足

次要评分

新颖性
-
重要性
-
科学严谨性
-
评价这篇论文

推荐

暂无数据
暂无数据