TY - JOUR
T1 - Surface engineering in improving activity of Pt nanocubes for ammonia electrooxidation reaction
AU - Siddharth, Kumar
AU - Hong, Youngmin
AU - Qin, Xueping
AU - Lee, Hye Jin
AU - Chan, Yat Tung
AU - Zhu, Shangqian
AU - Chen, Guohua
AU - Choi, Sang-Il
AU - Shao, Minhua
PY - 2020/7/15
Y1 - 2020/7/15
N2 - Ammonia (NH3) electro-oxidation reaction (AOR) is an important reaction in direct NH3 fuel cells, NH3 electrolyzer, and NH3-based electrochemical sensors. However, its slow kinetics and structure-sensitive properties require specific electrocatalyst designs. In this study, Ir-decorated Pt nanocubes are developed as unique surface engineered model catalysts. For the first time, we find that a trace amount of Ir (less than 2%) could increase the AOR activity of Pt nanocubes by more than twice. Theoretical simulation results also illustrate that the surface-decorated Ir could lower the energy barrier in the rate determining *NH formation step on Pt surfaces, thus increasing activity in accordance with experimental findings. Additionally, Ir and Ni(OH)2-decorated Pt nanocubes can significantly improve the durability. Our findings demonstrate the importance of surface engineering in catalyst synthesis and pave the way of advanced electrocatalyst designs for ammonia oxidation and other catalytic reactions.
AB - Ammonia (NH3) electro-oxidation reaction (AOR) is an important reaction in direct NH3 fuel cells, NH3 electrolyzer, and NH3-based electrochemical sensors. However, its slow kinetics and structure-sensitive properties require specific electrocatalyst designs. In this study, Ir-decorated Pt nanocubes are developed as unique surface engineered model catalysts. For the first time, we find that a trace amount of Ir (less than 2%) could increase the AOR activity of Pt nanocubes by more than twice. Theoretical simulation results also illustrate that the surface-decorated Ir could lower the energy barrier in the rate determining *NH formation step on Pt surfaces, thus increasing activity in accordance with experimental findings. Additionally, Ir and Ni(OH)2-decorated Pt nanocubes can significantly improve the durability. Our findings demonstrate the importance of surface engineering in catalyst synthesis and pave the way of advanced electrocatalyst designs for ammonia oxidation and other catalytic reactions.
KW - Ammonia electro-oxidation reaction
KW - Density functional theory calculations
KW - Electrocatalyst
KW - Iridium
KW - Platinum
UR - http://www.scopus.com/inward/record.url?scp=85080121001&partnerID=8YFLogxK
UR - https://www.scopus.com/record/pubmetrics.uri?eid=2-s2.0-85080121001&origin=recordpage
U2 - 10.1016/j.apcatb.2020.118821
DO - 10.1016/j.apcatb.2020.118821
M3 - RGC 21 - Publication in refereed journal
SN - 0926-3373
VL - 269
JO - Applied Catalysis B: Environmental
JF - Applied Catalysis B: Environmental
M1 - 118821
ER -
