CuO nanoparticle-functionalized cellulose-based aerogel as high-performance visible-light photocatalyst.

CuO nanoparticle (NP)-functionalized cellulose-based aerogel (CuO/CBA) with three-dimensional (3D) macroporous structure and abundant active sites was successfully prepared for visible-light photocatalysis via in situ deposition of CuO NPs on cellulose-based aerogel (CBA). Octahedral CuO NPs were formed and anchored onto the surface and inner wall of the cellulose matrix, which acted as a microreactor to prevent aggregation and protect the catalytic character of the CuO NPs. The photocatalytic performance of the CuO/CBA composite catalysts was evaluated using degradation of methylene blue (MB) as model pollutant. The effects of catalyst dosage, initial MB concentration, and solution pH on MB photodegradation were investigated. Use of 3D macroporous CBA improved the MB adsorption capacity and extended the absorption of visible-light irradiation. In particular, in situ deposition of CuO in the cellulose matrix enhanced separation of photogenerated electrons and holes via surface-adsorbed molecular oxygen, and consequently the catalytic activity. The photodegradation rate of MB by CuO/CBA composite catalyst reached 95.79%, much higher than the value of 73.59% for pure CuO. The photodegradation process on the CuO/CBA composite catalysts followed an apparent pseudo-first-order kinetic model. The CuO/CBA composite catalyst was easily recycled and reused, with 80% MB degradation rate retained even after six cycles of irradiation for 30 min each. Such CuO/CBA composite catalysts can be applied for wastewater treatment utilizing solar radiation. [ABSTRACT FROM AUTHOR]