PUBLICATION
Recent Papers (for full list, please click here)
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Cao, Y., Zhang, Q., Yu, I.K.M.*, Tsang, D.C.W.* Revealing OH species in situ generated on low-valence Cu sites for selective carbonyl oxidation. PNAS, 2024, 121, e2408770121.
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Yu, I.K.M.; Deng, F.; Chen, X.; Cheng, G.; Liu, Y.; Zhang, W.*; Lercher, L.A.* Impact of hydronium ions on the Pd-catalyzed furfural hydrogenation. Nat. Comm., 2022, 13, 7154. [Abstract]
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Yu, I.K.M.; Rechberger, H.; Gutberlet, J.; Istrate, I.; Parizeau, K.; Sanctuary, M.; McQuillian, H.; de Barcellos, M.D. Closing the waste gap. One Earth, 2022, 5, 1181-1184.
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Dutta, S.; Yu, I.K.M.; Fan, J.; Clark, J.H.; Tsang, D.C.W.* Critical factors for levulinic acid production from starch-rich food waste: Solvent effects, reaction pressure, and phase separation. Green Chem., 2022, 24, 163-175.
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Yu, I.K.M*. Mechanistic understandings of catalytic hydrogenation of bio-derived aromatics. Green Chem., 2021, 23, 9239-9253. [Abstract]
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Xiong, X.; Yu I.K.M.* ; Dutta, S.; Mašek, O.; Tsang, D.C.W.* Valorization of humins from food waste biorefinery for synthesis of biochar-supported Lewis acid catalysts. Sci. Total Environ., 2021, 775, 145851.
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Zhang, Q.; Wan, Z.; Yu, I.K.M.* ; Tsang, D.C.W.* Sustainable production of high-value gluconic acid and glucaric acid through oxidation of biomass-derived glucose: A critical review. J. Clean. Prod., 2021, 127745.
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Yu, I.K.M.; Fan, J.*; Budarin, V.L.*; Bouxin, F.P.; Clark, J.H.; Tsang, D.C.W.* Evidences of starch-microwave interactions under hydrolytic and pyrolytic conditions. Green Chem., 2020, 22, 7109-7118.
Yu et al., Nat. Comm., 2022, 13, 7154.
In aqueous mediums, the chemical environment for catalytic reactions is not only comprised of water molecules but also of corresponding ionized species, i.e., hydronium ions, which can impact the mechanism and kinetics of a reaction. Here we show that in aqueous-phase hydrogenation of furfural on Pd/C, increasing the hydronium ion activities by five orders of magnitude (from pH 7 to pH 1.6) leads to an increase of less than one order of magnitude in the reaction rate. Instead of a proton-coupled electron transfer pathway, our results show that a Langmuir-Hinshelwood mechanism describes the rate-limiting hydrogen addition step, where hydrogen atom adsorbed on Pd is transferred to the carbonyl C atom of the reactant. As such, the strength of hydrogen binding on Pd, which decreases with increasing hydronium ion concentration (i.e., 2 kJ molH2−1 per unit pH), is a decisive factor in hydrogenation kinetics (rate constant +270%). In comparison, furfural adsorption on Pd is pH-independent, maintaining a tilted geometry that favors hydrogen attack at the carbonyl group over the furan ring.
Yu, IKM. Green Chem., 2021,23, 9239-9253.
Biorefinery, the transformation of biomass to renewable energy and materials, is a prominent player in the sustainability agenda to achieve carbon neutrality in 30–40 years. In the reductive upgrading of bio-based aromatic compounds (e.g., furfural), disparity in the reported product profiles leads to a scientific question – what general principles govern the catalytic rate and selectivity towards certain paths? There are increasing pieces of evidence for metal–reactant interactions serving as the fundamental determinants of the reaction rate and product distribution. The binding strength and geometry of substrates depend on the coverage of the substrate itself as well as other surface species. Modifying metal electronic properties not only affects the state of the adsorbed organic substrate but also hydrogen binding as quantified by electrochemical characterization. This review addresses the issues above from the viewpoint of kinetics and thermodynamics, by aligning multi-disciplinary findings from catalyst evaluations, theoretical calculations, and electrochemical analyses, shedding light on the universal descriptors of catalytic hydrogenation.