Niobium pentoxide nanomaterials with distorted structures as efficient acid catalysts

authors	Skrodczky, K; Antunes, MM; Han, XY; Santangelo, S; Scholz, G; Valente, AA; Pinna, N; Russo, PA
nationality	International
journal	COMMUNICATIONS CHEMISTRY
keywords	USEFUL BIO-PRODUCTS; REDUCTIVE ETHERIFICATION; BRONSTED ACIDITY; ETHYL LEVULINATE; HYDROXYL-GROUPS; OXIDE; CONVERSION; RAMAN; NANOSHEETS; LEWIS
abstract	Niobium pentoxides are promising acid catalysts for the conversion of biomass into fuels and chemicals. Developing new synthesis routes is essential for designing niobium pentoxide catalysts with improved activity for specific practical processes. Here we show a synthesis approach in acetophenone, which produces nanostructured niobium pentoxides with varying structure and acidity that act as efficient acid catalysts. The oxides have orthorhombic structures with different extents of distortions and coordinatively unsaturated metal atoms. A strong dependence is observed between the type and strength of the acid sites and specific structural motifs. Ultrasmall niobium pentoxide nanoparticles, which have strong Bronsted acidity, as well as Lewis acidity, give product yields of 96% (3 h, 140 degrees C, 100% conversion), 85% (3 h, 140 degrees C, 86% conversion), and 100% (3 h, 110 degrees C, 100% conversion) in the reactions of furfuryl alcohol, 5-(hydroxymethyl)furfural, and a-angelica lactone with ethanol, respectively.
publisher	NATURE PUBLISHING GROUP
issn	2399-3669
year published	2019
volume	2
digital object identifier (doi)	10.1038/s42004-019-0231-3
web of science category	Chemistry, Multidisciplinary
subject category	Chemistry
unique article identifier	WOS:000496178400002