Photoproduction of green hydrogen using doped Cu-BDC MOFs
Résumé
The need for energy is growing rapidly around the world but it must cope with the significant environmental pollution challenges and depleting resources simultaneously. Solar-driven hydrogen production has gained attention as an environmentally friendly approach to address global energy demands for sustainable and clean energy in combating climate change [1]. Producing green hydrogen through photocatalytic water splitting is a clean and sustainable alternative to conventional methods like using fossil fuels or electrolysis. Metal-Organic Frameworks (MOFs), with their customizable structures, high surface area, and exceptional light-harvesting capabilities, have emerged as advanced materials for this process [2]. This research aims to synthesize photocatalytically active MOFs, specifically, copper 1,4-benzenedicarboxylate (CuBDC) as it is a promising MOF for photocatalytic hydrogen production due to its efficient light absorption and catalytic potential. In this study, we investigate the enhancement of CuBDC photocatalytic performance by doping with various transition metals to improve the hydrogen evolution reaction (HER) activity. Conventional CuBDC allows H2 photoproduction under visible light irradiation and a H2 production rate of 2500 µmol g-1 h-1 was achieved. Ni-doped CuBDC exhibits a much higher activity (5700 µmol g-1 h-1) and the highest activity is reached for Co-doped CuBDC (13000 µmol g-1 h-1), value almost six-fold higher than that of CuBDC. The prepared photocatalysts were characterized using FT-IR, XRD to assess their structural and chemical properties. SEM, TEM, and EDAX were carried out to study the morphology, size, elemental composition, and structure of the samples. UV-visible spectroscopy, photoluminescence (PL) and electrochemical impedance spectroscopy (EIS) measurements were conducted to determine their optical properties and charge separation efficiency. BET measurements were also performed to measure the specific surface area and porosity of the prepared MOFs. This work highlights the advancements in doped CuBDC MOFs and provides insights into the future development of MOF-based photocatalysts for sustainable energy applications.

