Noble metal-free zeolitic imidazolate framework-based composite for photocatalytic production of green hydrogen

Iqbal, Muhammad Umer (author), Rana, Surjyakanta (author), Zitnan, Michal (author), Ashling, Christopher W. (author), Pérez-Ramos, M. (author), Nadeem, Irfan (author), González-Rodríguez, Modesto (author), Galusek, Dušan (author), Núñez, Pedro (author), Wondraczek, Lothar (author), Velazquez, José Joaquín (author)

Photocatalytic water splitting could become a major pillar in addressing future demands for carbon-free energy supply. To develop noble-metal-free photocatalyst microstructures, a heterostructure photocatalytic system containing hexagonal Zeolitic Imidazolate Framework-8 (ZIF-8) and oxygen-deficient spherical CuWO▫$_{4}$▫ nanoparticles was designed. In addition to preventing CuWO▫$_{4}$▫ aggregation, ZIF-8 promotes the accessibility of active sites, interfacial charge transfer, and separation in the ZIF-8@CuWO▫$_{4}$▫ composite. In this composite, UV-visible diffuse reflectance spectroscopy reveals substantial light absorption in the UV range, while photoluminescence spectroscopy indicates suppressed electron-hole recombination relative to pristine materials. The as-synthesised ZIF-8@CuWO▫$_{4}$▫ exhibits a photocatalytic H▫$_{2}$▫ evolution rate of 2,531 μmol g▫$^{-1}$▫ h▫$^{-1}$▫ under UV irradiation, higher than that of pristine ZIF-8 and CuWO▫$_{4}$▫. The composite achieves a maximum H▫$_{2}$▫ production rate of 79 μmol g▫$^{-1}$▫ h▫$^{-1}$▫ under visible light irradiation using Na▫$_{2}$▫S/Na▫$_{2}$▫SO▫$_{3}$▫ (0.35/0.25 M) as the sacrificial hole scavenger. These results highlight that integrating ZIF-8 with CuWO▫$_{4}$▫ could offer an effective option for improving photocatalytic green hydrogen production in CuWO▫$_{4}$▫-based heterojunction systems.

• Language: English
• Keywords: CuWO4, composites, green hydrogen production, water splitting, ZIF-8
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FS - Faculty of Mechanical Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2026
• Number of pages: 23 str.
• Numbering: Vol. 6, art. 20260107
• PID: 20.500.12556/RUL-185801
• UDC: 544.526.5:678.061
• ISSN on article: 2770-2995
• DOI: 10.20517/microstructures.2026.58
• COBISS.SI-ID: 288336899
• Publication date in RUL: 20.08.2026

Record is a part of a journal

• Title: Microstructures
• Shortened title: Microstructures
• Publisher: OAE Publishing Inc.
• ISSN: 2770-2995
• COBISS.SI-ID: 142678787

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: CuWO4, kompoziti, proizvodnja zelenega vodika, razcep vode, ZIF-8