Physical Sciences and Mathematics Commons^™

On The Limited Role Of Electronic Support Effects In Selective Alkyne Hydrogenation: A Kinetic Study Of Au/MoX Catalysts Prepared From Oleylamine-Capped Colloidal Nanoparticles, James E. Bruno, K. B. Sravan Kumar, Nicolas S. Dwarica, Alexander Hüther, Zhifeng Chen, Clemente S. Guzman Iv, Emily R. Hand, William C. Moore, Robert M. Rioux, Lars C. Grabow, Bert D. Chandler

Chemistry Faculty Research

We report a quantitative kinetic evaluation and study of support effects for partial alkyne hydrogenation using oleylaminecapped Au colloids as catalyst precursors. The amine capping agents can be removed under reducing conditions, generating supported Au nanoparticles of ~2.5 nm in diameter. The catalysts showed high alkene selectivity (>90%) at all conversions during alkyne partial hydrogenation. Catalytic activity, observed rate constants, and apparent activation energies (25– 40 kJ/mol) were similar for all Au catalysts, indicating support effects are relatively small. Alkyne adsorption, probed with FTIR and DFT, showed adsorption on the support was associated with hydrogen-bonding interactions. DFT calculations indicate …