@misc{10481/86550,
year = {2022},
month = {10},
url = {https://hdl.handle.net/10481/86550},
abstract = {An environmentally friendly solvent-free approach was tested using spent coffee as a biomass sacrificial template for the preparation of TiO2 modified with CeOx. The use of coffee as a template pursues the preparation of a nanostructured heterojunction without the need for a solvent. Two variables were optimized in the synthesis process, i.e. calcination temperature and proportion of CeOx. Firstly, bare coffee-template titania was prepared to explore the effect of the calcination temperature, within 500–650 °C. The anatase phase was obtained up to 600 °C. Higher temperatures, i.e. 650 °C, led to the appearance of rutile (10%) and efficient removal of the sacrificial agent (0.6% residue). The maximum photocatalytic activity in terms of conversion, in the oxidation of benzyl alcohol, was achieved employing the bare coffee-template TiO2 at 650 °C, and it was found comparable to the benchmarked P25. The incorporation of ceria in the solvent-free approach considerably improved photocatalytic benzaldehyde production. No changes in the XRD pattern of TiO2 were appreciated in the presence of ceria due to the low amount added, within 1.5–6.0%, confirmed by XPS as superficial Ce3+/Ce4+. The UV–visible absorption spectra were considerably redshifted in the presence of Ce, reducing the bandgap values of bare titania. An optimum amount of ceria in the structure within 3-0% was found. In this case, the selectivity towards benzaldehyde was ca. 75%, 3 times higher than the selectivity value registered for the benchmarked P25 or the bare prepared TiO2.},
keywords = {Green synthesis},
keywords = {Solvent-free},
keywords = {Coffee-templated},
keywords = {Cerium},
keywords = {Titania},
keywords = {Photocatalysis},
keywords = {Benzaldehyde},
title = {Coffee-waste templated CeOx/TiO2 nanostructured materials for selective photocatalytic oxidations},
doi = {10.1016/j.chemosphere.2022.136672},
author = {Rodríguez Solís, Rafael and Rodríguez Padrón, Daily and Martín Lara, Mª Ángeles and Calero, Mónica and Luque, Rafael and Muñoz Batista, Mario J.},
}