Wenjing Huang,1 Xian-Yin Ma,2 Han Wang,3 Renfei Feng,4 Jigang Zhou,4 Paul N. Duchesne,5 Peng Zhang,5 Fengjiao Chen,1 Na Han,1 Feipeng Zhao,1 Junhua Zhou,1 Wen-Bin Cai,*3 and Yanguang Li*1
1Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou 215123, China
2Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power, Shanghai University of Electric Power, Shanghai 20090, China
3Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Collaborative Innovation Center of Chemistry for Energy Materials, Department of Chemistry, Fudan University, Shanghai 200433, China
4Canadian Light Source Inc. Saskatoon, Saskatchewan S7N 0X4, Canada
5Department of Chemistry, Dalhousie University, Halifax NS B3H 4R2, Canada
Most electrocatalysts for the ethanol oxidation reaction suffer from extremely limited operational durability and poor selectivity toward the C-C bond cleavage. In spite of tremendous efforts over the past several decades, little progress has been made in this regard. This study reports the remarkable promoting effect of Ni(OH)2 on Pd nanocrystals for electrocatalytic ethanol oxidation reaction in alkaline solution. A hybrid electrocatalyst consisting of intimately mixed nanosized Pd particles, defective Ni(OH)2 nanoﬂakes, and a graphene support is prepared via a two-step solution method. The optimal product exhibits a high mass-specifc peak current of>1500 mA mg−1Pd, and excellent operational durability forms both cycling and chronoamperometric measurements in alkaline solution. Most impressively, this hybrid catalystretains a mass-specifc current of 440 mA mg−1 even after 20 000 s of chronoamperometric testing, and its original activity can be regenerated via simple cyclic voltammetry cycles in clean KOH. This great catalyst durability is understood based on both CO stripping and in situ attenuated total reﬂection infrared experiments suggesting that the presence of Ni(OH)2 alleviates the poisoning of Pd nanocrystals by carbonaceous intermediates. The incorporation of Ni(OH)2 also markedly shifts the reaction selectivity from the originally predominant C2 pathway toward the more desirable C1 pathway, even at room temperature.