Producing hydrogen from biomass and seawater using immobilized carbon nitride photocatalysts

• Type: Article in International Scientific Journal
• Date: 2025

Authors

Machado, AL (Author) Other; Oliveira, RA (Author) Other; Drazic, G (Author) Other; Lopes, JC (Author) Other; Claudia G Silva (Author) FEUP; Faria, JL (Author) Other; Sampaio, M.J. (Author) FEUP

Journal

The Journal is awaiting validation by the Administrative Services.

Title: Chemical Engineering Journal Advances

Vol. 21

ISSN: 2666-8211

Indexing

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Associated Projects

SuN2Fuel - Produção foto-assistida de combustíveis verdes baseados em amoníaco

Other information

Authenticus ID: P-017-QMA

DOI: 10.1016/j.ceja.2024.100697

Abstract (EN): To address the challenges related with using powdered catalysts and freshwater in photocatalytic hydrogen (H2) production, this study explores the performance of carbon nitride-based catalyst immobilized on a 3D structure, employing seawater as a proton source. Methanol and saccharides such as cellobiose, fructose, glucose, saccharose and sorbitol were used as sacrificial agents to accelerate H2 production via photoreforming. The results using immobilized photocatalyst showed that, at similar molar concentrations, glucose reveals higher efficiency compared with methanol, achieving an amount of H2 evolution of 102 mu mol after 180 min under visible light, compared to 45 mu mol with methanol. Among the mono- and polysaccharides used, cellobiose has emerged as the most promising for H2 evolution, achieving the highest amount of H2 (124 mu mol) after 180 min reaction. This result suggests a correlation between the efficiency of scavenging holes and the number of hydroxyl groups in the electron donor's structure. Despite a slight decrease in H2 evolution compared with the powdered catalysts, the use of immobilized photocatalyst exhibited remarkable stability in both ultrapure water and seawater, maintaining its performance across multiple reuse cycles. The photocatalytic system demonstrated remarkable efficiency for H2 production, avoiding phases separation processes, promotes the transition to continuous flow reactors and preserve freshwater resources.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10