Boosted Photocatalytic Activities of Ag<sub>2</sub>CrO<sub>4</sub> through Eu<sup>3+</sup>-Doping Process
Josiane Carneiro Souza, Samantha C.S. Lemos, Marcelo Assis, Carlos H.M. Fernandes, Lara Kelly Ribeiro, Yeison Núñez‐de la Rosa, M. D. Teodoro, Lourdes Gracia, Juán Andrés, Lúcia H. Mascaro, E. Longo
Abstract
High Resolution Image Download MS PowerPoint Slide Ag 2 CrO 4 is a representative member of a family of Ag-containing semiconductors with highly efficient visible-light-driven responsive photocatalysts. The doping process with Eu 3+ is known to effectively tune their properties, thus opening opportunities for investigations and application. Here, we report the enhancement of the photocatalytic activity and stability of Ag 2 CrO 4 by introducing Eu 3+ cations. The structural, electronic, and photocatalytic properties of Ag 2 CrO 4: x Eu 3+ ( x = 0, 0.25, 0.5, 1%) synthesized using the coprecipitation method were systematically discussed, and their photodegradation activity against rhodamine B (RhB), ciprofloxacin hydrochloride monohydrate (CIP), and 4-nitrophenol (4-NP) was evaluated. Structural analyses reveal a short-range symmetry breaking in the Ag 2 CrO 4 lattice after Eu 3+ doping, influencing the material morphology, size, and electronic properties. XPS analysis confirmed the incorporation of Eu 3+ and alteration of the surface oxygen species. Furthermore, photoluminescence measurements indicated that the doping process was responsible for reducing recombination processes. The sample doped with 0.25% Eu 3+ exhibited superior photocatalytic performance compared to pure Ag 2 CrO 4 . Scavenger experiments revealed an increase in the degradation via • OH reactive species for the sample doped with 0.25% Eu 3+ . DFT calculations provided atomic-scale insights into the structural and electronic changes induced by the Eu 3+ doping process in the Ag 2 CrO 4 host lattice. This study confirms that Eu 3+ doping alters the band structure, enabling different degradation paths and boosting the separation/transfer of photogenerated charges, thereby improving the overall photocatalytic performance.