Solidophobic Surface for Electrochemical Extraction of High-Valued Mg(OH)2 Coupled with H2 Production from Seawater

Li Yi; Xu Chen; Yingjie Wen; Haocheng Chen; Sixie Zhang; Hao Yang; Wenbo Li; Lihui Zhou; Beibei Xu; Wenwen Xu; Wanbing Guan; Sheng Dai; Zhiyi Lu

doi:10.1021/acs.nanolett.4c01484

Solidophobic Surface for Electrochemical Extraction of High-Valued Mg(OH)₂ Coupled with H₂ Production from Seawater

Nano Lett. 2024 May 15;24(19):5920-5928. doi: 10.1021/acs.nanolett.4c01484. Epub 2024 May 6.

Authors

Li Yi^{1

2}, Xu Chen¹, Yingjie Wen¹, Haocheng Chen^{1

2}, Sixie Zhang^{1

3}, Hao Yang^{1

2}, Wenbo Li⁴, Lihui Zhou⁴, Beibei Xu⁵, Wenwen Xu¹, Wanbing Guan^{1

3}, Sheng Dai⁴, Zhiyi Lu^{1

3}

Affiliations

¹ Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Advanced Fuel Cells and Electrolyzers Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, Zhejiang, China.
² College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310032, China.
³ University of Chinese Academy of Sciences, Beijing 100049, China.
⁴ Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Centre, Frontiers Science Center for Materiobiology and Dynamic Chemistry, Institute of Fine Chemicals, School of Chemistry and Molecular Engineering, East China University of Science & Technology, Shanghai 200237, China.
⁵ Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China.

PMID: 38708934
DOI: 10.1021/acs.nanolett.4c01484

Abstract

A significant challenge in direct seawater electrolysis is the rapid deactivation of the cathode due to the large scaling of Mg(OH)₂. Herein, we synthesized a Pt-coated highly disordered NiCu alloy (Pt-NiCu alloy) electrode with superior solidophobic behavior, enabling stable hydrogen generation (100 mA cm^-2, >1000 h durability) and simultaneous production of Mg(OH)₂ (>99.0% purity) in electrolyte enriched with Mg²⁺ and Ca²⁺. The unconventional solidophobic property primarily stems from the high surface energy of the NiCu alloy substrate, which facilitates the adsorption of surface water and thereby compels the bulk formation of Mg(OH)₂ via homogeneous nucleation. The discovery of this solidophobic electrode will revolutionarily simplify the existing techniques for seawater electrolysis and increase the economic viability for seawater electrolysis.

Keywords: double-product; high disorder alloy; high-purity Mg(OH)2; natural seawater electrolysis; solidophobic; surface energy.