Engineering Sulfide-Phosphide Based Double Catalysts on 3D Nickel Phosphides Framework for Electrolytic Hydrogen Evolution: Activating Short-range Crystalline MoS2 with Ni5P4-Ni2P Template. Issue 2 (24th January 2020)

• Record Type: Journal Article
• Authors: Yu, Shu Hearn; Chen, Wenzhou; Wang, Hongyu; Haiwen, Dai; Ng, Zhen Quan Cavin; Pan, Hui; Chua, Daniel H. C.
• Is Part Of: Journal of the Electrochemical Society. Volume 167:Issue 2(2020)
• Publication Date: 2020-01-24
• Subjects: Electrochemistry -- Periodicals; 541.3705
• DOI: 10.1149/1945-7111/ab6a85
• Languages: English
• ISSNs: 0013-4651

Abstract

Abstract : It is a universal quest to produce molecular hydrogen (H2 ) from sustainable green routes to diversify the heavy dependence of fossil fuels for energy consumption. Developing earth-abundant electrocatalysts for water electrolysis is a promising method to generate hydrogen via hydrogen evolution reaction (HER). In this work, we strategically promote electron transport and activate the basal planes of MoS2 via a thermal hybridization with vertically-aligned hierarchical nickel phosphide Ni5 P4 -Ni2 P (denoted as MoS2 /Ni5 P4 -Ni2 P) for HER. The metallic-like Ni5 P4 -Ni2 P foam promotes electron transportation into the MoS2 matrix by electron injection due to the difference of their Fermi levels. Moreover, MoS2 basal planes are activated by Ni5 P4 -Ni2 P due to phosphorus doping effects, triggering additional actives sites and boosting the overall HER performances. Notably, the HER performance of MoS2 /Ni5 P4 -Ni2 P electrode only requires an overpotential of 96 mV to reach a geometric current density of −10 mA cm −2 with relatively low Tafel slope of 74 mV dec −1 . The catalytic performances can last for at least 22 h at −10 mA cm −2 without discernible degradation, indicating the extraordinary long-term operation stability. This work provides insights into the synergistic effects of a hybridized catalyst, which may potentially serve as a next-generation electrocatalyst for efficient water splitting.