New catalyst design breaks down toxic water pollutants faster and cheaper
Researchers have developed a dual-shell photocatalyst that generates reactive oxygen species more efficiently, accelerating the breakdown of emerging contaminants in water. The advance could lower treatment costs for water utilities and manufacturers dealing with pharmaceuticals, pesticides, and industrial chemicals that conventional systems struggle to remove.
Originaltitel: Enhanced reactive oxygen species generation via a full-spectrum dual-shell photocatalyst towards effective degradation of emerging contaminants
<p>Reactive oxygen species (ROSs) offer strong oxidation capability for water purification, but their practical application is hindered by low energy transfer efficiency and fast exciton recombination. Herein, we construct a dual-shell UCMPs@g-C3N4@MSEP architecture through an integrated energy cascade regulation strategy. This architecture incorporates upconversion microparticles (UCMPs) for broadband spectral harvesting, along with an intimately interfaced g-C3N4 interlayer that achieves exceptional energy transfer efficiency exceeding 69.5%, thereby boosting ROSs generation by 1.7-fold. The second shell consists of magnetic sepiolite (MSEP), significantly enhancing surface hydrophilicity. This composite degrades 98.2% of ofloxacin within 40 min in various aqueous matrices, representing a 2.6-fold improvement over conventional g-C3N4. Experimental and theoretical analyses jointly confirm that the dual-shell configuration suppresses charge-carrier recombination. Liquid chromatography-mass spectrometry (LC-MS) was used to trace degradation intermediates and pathways. Toxicity assessment further confirmed that the photocatalytic process posed lower environmental risk. The enhanced activity arises from extended near-infrared light absorption via UCMPs and improved exciton separation enabled by the dual-shell design. This study offers a viable and environmentally benign strategy for efficient solar-driven water purification.</p>