A comparative study of BiFeO3-based compounds for enhanced hydrogen evolution reaction
Manal Benyoussef, Yassine Nassereddine, Sébastien Saitzek, Jean‐François Blach, M. El Marssi, Adlane Sayede, Mustapha Jouiad
Abstract
• Theoretical predictions reveal that BiFeO 3 substitutions can tailor the band gap. • Substituted BiFeO 3 compounds exhibit appropriate band alignment with water redox potential. • Photoelectrochemical measurements reveal high hydrogen yields of BiFeO 3 -25SrTiO 3 . • Substitution via solid solutions offers a promising approach to boost hydrogen yields. We present a comprehensive study, combining experimental and theoretical approaches, to assess the hydrogen evolution reaction (HER) efficiency of BiFeO 3 -based solid solutions. Initially, we investigate the electronic and optical properties of these compounds, with a particular focus on band edge alignment relative to water redox potentials. Our findings show that the materials exhibit optimal band gaps of approximately 2.0 eV, indicative of enhanced visible light absorption and favorable energetic alignment to drive efficient hydrogen generation. To corroborate our theoretical predictions, we perform photoelectrochemical measurements on selected BiFeO 3 -based compounds synthesized via the solid-state method. Our experimental results reveal a high hydrogen yield, with BiFeO 3 -SrTiO 3 achieving a production rate of ∼114 µmol/L in 30 min, outperforming BiFeO 3 -BaTiO 3 (∼70 µmol/L) and pristine BiFeO 3 (∼61 µmol/L). These findings validate our theoretical assumptions and demonstrate the superior HER performance of BiFeO 3 -SrTiO 3 , positioning it as a highly promising candidate for sustainable hydrogen production.