Enhanced seawater photocatalytic hydrogen generation using copper-loaded TiO₂
Malaz SULIMAN, Muhammad TAHIR
Abstract. Hydrogen (H₂) is increasingly recognized as a promising renewable energy carrier, capable of addressing the intermittency issues associated with renewable energy sources due to its ability to store energy over long periods. Photocatalytic seawater splitting holds significant promise but remains highly challenging due to the presence of various ions in seawater, which can hinder the photocatalyst’s activity. However, the specific mechanisms by which these ions interfere with photocatalytic hydrogen production are still not well understood. This study investigates the performance of Cu-loaded TiO₂ (Cu/TiO2) photocatalyst synthesized via wet impregnation for simulated seawater splitting (3.5% NaCl) using 5 vol% methanol as a sacrificial agent, aiming to enhance the hydrogen production by TiO₂ in seawater conditions. Different copper loadings ranging from 1 to 5 wt.% were tested under a 65 W lamp, and the results revealed that the highest hydrogen yield was achieved using 4 wt.% Cu/TiO2, producing 883.15 μmol g-1 h-1 compared to only 310.18 μmol g-1 h-1 using pure TiO₂ under simulated seawater conditions. This increase is primarily due to enhanced light absorption and reduced charge carrier recombination. By utilizing copper, an earth-abundant and inexpensive metal, this study provides a cost-effective and environmentally friendly approach to improve TiO₂ performance for photocatalytic hydrogen production in seawater. These findings demonstrate a feasible pathway for efficient solar hydrogen generation directly from seawater.
Keywords
Seawater Splitting, Hydrogen Evolution, Doping, Titanium Dioxide, Copper
Published online 6/20/2026, 7 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Malaz SULIMAN, Muhammad TAHIR, Enhanced seawater photocatalytic hydrogen generation using copper-loaded TiO₂, Materials Research Proceedings, Vol. 67, pp 340-346, 2026
DOI: https://doi.org/10.21741/9781644904176-46
The article was published as article 46 of the book Climate Action and Sustainability
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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