Hierarchical NiMo-based 3D electrocatalysts for highly-efficient hydrogen evolution in alkaline conditions

• Published in: Nano energy 2016-09, Vol.27, p.247-254
• Main Authors: Fang, Ming, Gao, Wei, Dong, Guofa, Xia, Zhaoming, Yip, SenPo, Qin, Yuanbin, Qu, Yongquan, Ho, Johnny C.
• Format: Article
• Language: English
• Subjects: Electrocatalysis; Hierarchical nanostrutures; Hydrogen evolution; Nickel-molybdenum alloys
• ISSN: 2211-2855
• DOI: 10.1016/j.nanoen.2016.07.005

In recent years, electro- or photoelectrochemical water splitting represents a promising route for renewable hydrogen generations but still requires the substantial development of efficient and cost-effective catalysts to further reduce the energy losses and material costs for scalable and practical applications. Here, we report the design and development of a hierarchical electrocatalyst constructed from microporous nickel foam and well-assembled bimetallic nickel-molybdenum (NiMo) nanowires, which are capable to deliver current densities as comparable to those of the state-of-the-art Pt/C catalyst at low overpotentials and even larger current densities at higher overpotentials (>124mV). This binder-free 3D hydrogen evolution cathode catalyst also exhibits the excellent stability, without any decay of the current density observed after long-term stability tests at a low current density of 10mAcm−2 and a high current density of 50mAcm−2. By pairing this NiMo 3D cathode with a NiFe-based anode, a water electrolyzer can be achieved with a stable current density of 10mAcm−2 for overall water splitting at a voltage of ~1.53V, indicating that the water splitting can be indeed realized without any performance sacrifice by using earth abundant electrocatalysts. A hierarchical electrocatalyst is constructed from microporous nickel foam and well-assembled bimetallic nickel-molybdenum (NiMo) nanowires, which is capable to catalyze hydrogen evolution with an activity comparable to that of state-of-the art precious Pt/C catalyst. [Display omitted] •Nanostructured NiMo alloy can catalyse HER comparable to that does by Pt/C.•This 3D catalyst also shows excellent stability over long-term tests.•A current density of 10 mA cm-2 achieved for overall water splitting at 1.53 V.