Abstract

Developing efficient bifunctional catalysts for overall water splitting that are earth-abundant, cost-effective, and durable is of considerable importance from the practical perspective to mitigate the issues associated with precious metal-based catalysts. Herein, we introduce a heterostructure comprising perovskite oxides (La0.5Sr0.5CoO3–δ) and molybdenum diselenide (MoSe2) as an electrochemical catalyst for overall water electrolysis. Interestingly, formation of the heterostructure of La0.5Sr0.5CoO3–δ and MoSe2 induces a local phase transition in MoSe2, 2 H to 1 T phase, and more electrophilic La0.5Sr0.5CoO3–δ with partial oxidation of the Co cation owing to electron transfer from Co to Mo. Together with these synergistic effects, the electrochemical activities are significantly improved for both hydrogen and oxygen evolution reactions. In the overall water splitting operation, the heterostructure showed excellent stability at the high current density of 100 mA cm−2 over 1,000 h, which is exceptionally better than the stability of the state-of-the-art platinum and iridium oxide couple.

While catalysts are necessary for H2 and O2 production from water, developing materials capable of evolving both under the same conditions has proven challenging. Here, authors prepare perovskite-oxide and molybdenum sulfide heterostructures as bifunctional water-splitting electrocatalysts.

Details

Title
In-situ local phase-transitioned MoSe2 in La0.5Sr0.5CoO3-δ heterostructure and stable overall water electrolysis over 1000 hours
Author
Oh Nam Khen 1 ; Kim, Changmin 2 ; Lee, Junghyun 1 ; Kwon Ohhun 2 ; Choi Yunseong 1 ; Jung, Gwan Yeong 2 ; Lim, Hyeong Yong 2 ; Kwak, Sang Kyu 2   VIAFID ORCID Logo  ; Kim Guntae 2 ; Park Hyesung 1 

 Ulsan National Institute of Science and Technology (UNIST), Department of Energy Engineering, School of Energy and Chemical Engineering, Low Dimensional Carbon Materials Center, Perovtronics Research Center, Ulsan, Republic of Korea (GRID:grid.42687.3f) (ISNI:0000 0004 0381 814X) 
 Ulsan National Institute of Science and Technology (UNIST), Department of Energy Engineering, School of Energy and Chemical Engineering, Ulsan, Republic of Korea (GRID:grid.42687.3f) (ISNI:0000 0004 0381 814X) 
Publication year
2019
Publication date
2019
Publisher
Nature Publishing Group
e-ISSN
20411723
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2208722867
Copyright
© The Author(s) 2019. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.