10.1021/acs.jpcc.6b12720.s001
Wei An
Wei
An
Yong Men
Yong
Men
Jinguo Wang
Jinguo
Wang
Ping Liu
Ping
Liu
Interfacial and Alloying Effects on Activation of
Ethanol from First-Principles
American Chemical Society
2017
EOR
engineering alloyed structure
first-principles density-functional theory study
OH
Rh 1 Cu 3
Rh ensemble sizes
DEFC anode
Rh 1 Pd 3
ethanol fuel cell
Rh 1 Ir 3
CO
SRE
Rh 1 Ru 3 surface alloys
MO x chain
ethanol oxidation reaction
2017-02-24 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Interfacial_and_Alloying_Effects_on_Activation_of_Ethanol_from_First-Principles/4715212
We
present a first-principles density-functional theory study of
ethanol activation at oxide/Rh(111) interface and the alloying effect
on mitigating carbon deposition, which are essential to direct ethanol
fuel cell (DEFC) anode reaction and steam reforming of ethanol (SRE)
reaction. Our calculated results show that charge can transfer from
Rh(111) substrate to MO<sub><i>x</i></sub> chain (e.g.,
MoO<sub>3</sub> and MnO<sub>2</sub>), or from MO<sub><i>x</i></sub> chain (e.g., MgO, SnO<sub>2</sub>, ZrO<sub>2</sub>, and TiO<sub>2</sub>) to Rh(111) substrate. The OH-binding strength is increased
exponentially with M<sup>δ+</sup> charge ranging from 1.4 to
2.2, which renders MnO<sub>2</sub>/Rh(111) and MgO/Rh(111) interfaces
weaker OH-binding, and thereby enhanced oxidizing functionality of
OH* for promoting ethanol oxidation reaction (EOR) at DEFC anode.
For efficient C–C bond breaking, a large number of Rh ensemble
sizes are critically needed at the interface of MO<sub><i>x</i></sub>/Rh(111). We found that Rh<sub>1</sub>Au<sub>3</sub> near surface
alloy has the weakest C* and CO* binding, followed by Rh<sub>1</sub>Cu<sub>3</sub> and Rh<sub>1</sub>Pd<sub>3</sub> near surface alloys,
while Rh<sub>1</sub>Ir<sub>3</sub> and Rh<sub>1</sub>Ru<sub>3</sub> surface alloys have C* and CO* binding strength similar to that
of pure Rh metal. The general implication of this study is that by
engineering alloyed structure of weakened C* and CO* binding complemented
with metal oxides of weakened OH-binding, high-performance DEFC anode
or SRE catalysts can be identified.