open access publication

Article, 2024

Enabling direct seawater electrolysis by redox-inactive amphiphilic amines via chloride sequestration

Chemical Engineering Journal, ISSN 1385-8947, Volume 496, 10.1016/j.cej.2024.153763

Contributors

Milia M. [1] Choi Y. 0000-0001-8903-3551 [2] Lima R.J.S. 0000-0003-1528-845X [1] Na K. 0000-0001-5591-449X (Corresponding author) [2] Lee J.-W. 0000-0001-6177-4569 [1]

Affiliations

  1. [1] University of Copenhagen
  2. [NORA names: KU University of Copenhagen; University; Denmark; Europe, EU; Nordic; OECD];
  3. [2] Chonnam National University
  4. [NORA names: South Korea; Asia, East; OECD]

Abstract

Sustainable hydrogen production requires large amounts of treated freshwater and precious metals. Direct electrolysis of seawater without additional electrolytes can be a practical approach to address these limitations, however, it usually suffers from kinetically favored chlorine evolution reaction (CER), which is detrimental to an electrolysis system. We report that organocatalytic amphiphilic diamines play a crucial role in preventing the generation of chlorine gas. The feasibility of direct seawater electrolysis was demonstrated with pH-responsive organic amines, which can self-assemble under neutral and acidic conditions. Electrochemical analysis of our electrolysis in saline solutions revealed that (electro)chemical stability of amphiphilic diamines was responsible for preventing CER and hypochlorite formation. Our findings may have significant implications for the chemical industry and energy sectors as the world transitions towards renewable energy sources.

Keywords

Chlorine, Electrolysis, Hydrogen, Organocatalyst, Seawater

Funders

  • Ministry of Science, ICT and Future Planning
  • Department of Chemistry University of Copenhagen
  • Danmarks Frie Forskningsfond
  • National Research Foundation
  • Villum Fonden
  • Carlsbergfondet

Data Provider: Elsevier