Selective (sono)photocatalytic cleavage of lignin-inspired β–O–4 linkages to phenolics by ultrasound derived 1-D titania nanomaterials

• Published in: Ultrasonics sonochemistry Vol. 104; p. 106829
• Main Authors: Qayyum, Abdul, Giannakoudakis, Dimitrios A., Łomot, Dariusz, Fernando Colmenares-Quintero, Ramón, Nikiforow, Kostiantyn, LaGrow, Alec P., Carlos Colmenares, Juan
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.03.2024; Elsevier
• Subjects: Biomass valorization; Catalysis under ultrasound irradiation; SonoPhotoCatalysis; Titania nanostructure; Ultrasonication; β-O-4 linkages; Ultrasonication; Titania nanostructure; SonoPhotoCatalysis; Biomass valorization; β-O-4 linkages
• ISSN: 1350-4177; 1873-2828
• DOI: 10.1016/j.ultsonch.2024.106829

[Display omitted] •Ultrasonication was successful utilized as a synthetic tool for novel TiOx photocatalyst.•Ultrasounds led to 1-D nanostructures with interesting physicochemical features.•Optimization of ultrasound power play a key role on the synthesis of the titania samples.•Our novel ultrasound-derived titanate sample showed elavated β-O-4 selective cleavage.•Sonophotocatalytic studies revealed the higher selective conversion of lignin inspired model compound to the phenolics than photocatalytic studies. Catalytic conversion of lignin to value-added aromatic compounds is still an open challenge, since the selective cleavage of the linkages interconnecting the aromatic molecules, especially the β-O-4 ones, is not efficiently achieved yet. Herein, novel titania-based nanostructured materials were synthesized using low-power-low-frequency ultrasound that demonstrated high efficiency for the selective cleavage of Cα-Cβ bond of β-O-4 linkages of lignin-inspired model compounds. Going a step ahead, experiments of sonophotocatalytic valorization of 2-phenoxy-1-phenylethanol were contacted for the first time, where the exposure to ultrasound leading to better conversion and selectivity towards the desired products in the case of the novel ultrasound-synthesized nano-photocatalyst. Mechanistic insights showcased that photogenerated holes are the main active species in the catalytic process. In general, this research work provides a green, effective, and cost-effective approach for the selective and efficient catalytic lignin valorization.