(665e) Laser-Made Mixed-Metal Hydroxide Nanocatalysts for Selective Electrooxidation of Toluene to Benzyl Alcohol

Electrocatalysis of hydrocarbons to selectively produce alcohols has the potential to transform the manufacturing of chemicals and consumer goods in a sustainable way by replacing existing fossil-fuel-based processes by energy-saving successor technologies that utilize renewable energy.¹ Selective hydrocarbon oxidations to alcohols have the ultimate goal of gas-to-liquid conversion of methane to methanol without energy-intensive steam reforming. Better catalysts, reaction control, and understanding of electrocatalytic processes are needed to achieve high selectivity for single alcohol products at high activity. Arresting the oxidation of hydrocarbons at alcohols without the generation of overoxidized products is challenging because the first oxidation is thermodynamically most difficult and further oxidations are energetically downhill. We developed earth-abundant mixed-metal (hydr)oxide nanocatalysts that were synthesized by pulsed laser in liquids synthesis² and employed them on high-surface-area carbon supports³ to selectively electrooxidize toluene to benzyl alcohol. We show how electrolyte engineering and concomitant accessibility of different mechanistic pathways led to 100 % selectivity for benzyl alcohol with an unprecedentedly high toluene conversion efficiency of >85 %. We also revealed the mechanistic underpinnings of this remarkable performance of laser-made nanocatalysts for the electrooxidation of toluene to benzyl alcohol.

(1) Taseska, T.; Yu, W.; Wilsey, M. K.; Meng, Z.; Cox, C. P.; Ngarnim, S. S.; Müller, A. M. Analysis of the Scale of Global Human Needs and Opportunities for Sustainable Catalytic Technologies. Top. Catal. 2023, DOI:10.1007/s11244-023-01799-3.

(2) Forsythe, R. C.; Cox, C. P.; Wilsey, M. K.; Müller, A. M. Pulsed Laser in Liquids Made Nanomaterials for Catalysis. Chem. Rev. 2021, 121, 7568-7637.

(3) Wilsey, M. K.; Watson, K. R.; Fasusi, O. C.; Yegela, B. P.; Cox, C. P.; Raffaelle, P. R.; Cai, L.; Müller, A. M. Selective Hydroxylation of Carbon Fiber Paper for Long-Lasting Hydrophilicity by a Green Chemistry Process. Adv. Mater. Interfaces 2023, 10, 2201684.