In a groundbreaking development poised to impact the energy and environmental sectors, researchers have unveiled a novel approach to enhancing photocatalytic degradation of pharmaceutical pollutants. The study, led by Ricardo Barbosa from the Programa de Pós-Graduação em Engenharia Física at Universidade Federal Rural de Pernambuco, introduces a new method for synthesizing Gd³⁺/Cu²⁺ co-doped ZnO photocatalysts. This innovation could revolutionize water treatment technologies and open new avenues for energy-efficient solutions.
The research, published in the journal *Discover Materials* (translated as *Discover Materials* in English), focuses on the synthesis of ZnO photocatalysts doped with gadolinium (Gd³⁺) and copper (Cu²⁺) using a sonochemical-assisted coprecipitation method. This technique not only improves the structural and optical properties of ZnO but also significantly enhances its photocatalytic performance.
“Our goal was to explore the synergistic effects of co-doping ZnO with rare-earth and transition metals to improve its efficiency in degrading pharmaceutical pollutants under UV irradiation,” explained Barbosa. The team synthesized various compositions of ZnO, including Zn1 − x−yGdxCuyO, with different ratios of Gd³⁺ and Cu²⁺. The results were striking: the Zn0.96Gd0.02Cu0.02O sample (ZGC22) exhibited the smallest crystallite size (~6 nm), a high BET surface area (~57 m²/g), and a narrowed band gap, which enhanced UV absorption.
The morphological analysis revealed a transition from well-defined rods in undoped ZnO to dense, cauliflower-like nanoparticle agglomerates in the ZGC22 sample, and to more open, flaky aggregates at higher Cu levels. This structural evolution played a crucial role in the enhanced photocatalytic activity. Under UV irradiation, the ZGC22 sample achieved 70% degradation of furosemide after 180 minutes, outperforming undoped ZnO (55%) and the higher-Cu sample (44%).
Scavenger tests identified hydroxyl radicals (•OH) as the dominant reactive species responsible for the degradation process. Moreover, reuse experiments demonstrated that the ZGC22 sample retained more than 90% of its degradation efficiency after multiple cycles, highlighting its stability and potential for long-term use.
The implications of this research are far-reaching. “This study not only advances our understanding of the role of rare-earth and transition metal doping in ZnO but also paves the way for developing more efficient and sustainable photocatalytic materials,” Barbosa noted. The enhanced photocatalytic performance of the co-doped ZnO could lead to more effective water treatment technologies, reducing the environmental impact of pharmaceutical pollutants.
In the energy sector, the improved efficiency of these photocatalysts could contribute to the development of more energy-efficient processes for water purification and other environmental applications. As the demand for clean water and sustainable energy solutions continues to grow, innovations like this are crucial for addressing global challenges.
The research published in *Discover Materials* marks a significant step forward in the field of photocatalysis. By leveraging the unique properties of Gd³⁺/Cu²⁺ co-doped ZnO, Barbosa and his team have demonstrated a promising approach to enhancing the performance of photocatalytic materials. This work not only highlights the potential of rare-earth and transition metal doping but also sets the stage for future developments in the field, offering new possibilities for energy-efficient and environmentally friendly solutions.