ZnO/Carbon xerogel photocatalysts by low-pressure plasma treatment, the role of the carbon substrate and its plasma functionalization
| Autor: | Yan Busby, Nikolay Tumanov, Laurent Houssiau, Yingying Wang, Nathalie Job, Jean-François Colomer, Jean-Jacques Pireaux, Vaios Stergiopoulos, Emile Haye, Margot Cardinal, Bao-Lian Su, Sébastien Penninckx |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
ZnO nanoparticles
Substrate (chemistry) chemistry.chemical_element Nanoparticle 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences Surfaces Coatings and Films Electronic Optical and Magnetic Materials Nanomaterials Biomaterials chemistry.chemical_compound Plasma Colloid and Surface Chemistry Adsorption chemistry Chemical engineering Photocatalysis Rhodamine B Surface modification 0210 nano-technology Carbon |
| Zdroj: | Journal of Colloid and Interface Science. 570:312-321 |
| ISSN: | 0021-9797 |
| Popis: | ZnO is known to be photocatalytic, but with limited performances due to the strong electron-hole recombination after irradiation. The integration of ZnO nanomaterials on a conductive and high surface area carbon substrate is thus a potential alternative to obtain a significant improvement of the photocatalytic performance. Moreover, the carbon functionalization is expected to have a significant role in the adsorption/degradation mechanisms of dye, due to the difference in wettability or surface charge. In this view, ZnO photocatalytic nanoparticles have been deposited on high surface area carbon xerogel substrate (CXG), using a new and original plasma process, consisting in the degradation of a solid organometallic directly on the carbon substrate (no gaseous precursor). In addition to the ZnO nanoparticle formation, the plasma treatment allows the carbon functionalization. The ZnO/CXG composite has been tested for the degradation of Rhodamine B (RhB) in aqueous media and compared with and O2 or NH3 plasma-treated xerogels (without nanoparticles) to identify the significant role of the substrate and its modification in the RhB adsorption and degradation mechanism. The high photocatalytic activity of ZnO/CXG composite is attributed to (i) the formation of small (8–10 nm) and well-crystallized ZnO nanoparticles anchored to the carbon substrate and (ii) to the modification of the xerogel surface chemistry. Indeed, O2 plasma treatment of the CXG promotes the generation of hydroxyl, carbonyl and carboxyl surface functional groups, which are polar and acidic, while the NH3 plasma treatment mainly leads to the formation of polar and basic amino groups. While both plasma treatments promote the formation of polar functional groups, which enhance the CXG wettability, the formation of acidic groups is identified as beneficial for the adsorption of the RhB dye, while basic groups are detrimental. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect