Enhanced photocatalytic green hydrogen production of naturally occurring serpentine over thermally exfoliated graphitic carbon nitride
Yahia ALANIZAN, Muhammad TAHIR
Abstract. Naturally occurring serpentine 1D nanotubes support and co-catalyst was coupled with 2D thermally exfoliated graphitic carbon nitride g-C3N4 via simple wet impregnation to achieve green hydrogen production through a simple, low-cost, sustainable, and noble metal-free approach. The Serp/g-C3N4 composite exhibited enhanced photocatalytic water splitting performance under visible light irradiation and resulted in the best average H2 yield of 3.1 µmol g-1 h-1 at 3% Serp/g-C3N4, indicating 2.1-fold, over bare g-C3N4 with 1.5 µmol g-1 h-1. The enhanced H2 results are attributed to enhanced charge separation, good dispersion, higher surface area, and enhanced wettability due to the hydrophilic Si–OH bond in serpentine structure. Milling the naturally occurring serpentine rock lowered the band gap from reported value of 4.7 eV to 3.86 eV due to oxygen vacancies obtained by milling process. This study investigates the improved visible light irradiation photocatalytic water splitting green hydrogen production performance using the abundant naturally occurring serpentine rock as support and co-catalyst coupled with g-C3N4.
Keywords
Photocatalysis, Green Hydrogen, Water Splitting, Sustainability, Carbon Nitride, Natural Material, Serpentine
Published online 6/20/2026, 8 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Yahia ALANIZAN, Muhammad TAHIR, Enhanced photocatalytic green hydrogen production of naturally occurring serpentine over thermally exfoliated graphitic carbon nitride, Materials Research Proceedings, Vol. 67, pp 415-422, 2026
DOI: https://doi.org/10.21741/9781644904176-56
The article was published as article 56 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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