REVIEW The development of gold catalysts for use in hydrogenation reactions Fernando Ca ´rdenas-Lizana • Mark A. Keane Received: 7 May 2012 / Accepted: 25 July 2012 Ó Springer Science+Business Media, LLC 2012 Abstract With increasing emphasis placed on cleaner chemical synthesis, energy efficiency and waste minimi- sation, the manufacture of pharmaceuticals and fine chemicals is undergoing a progressive shift from con- ventional stoichiometric organic processes to a harnessing of catalytic selectivity. In hydrogenation processes, gold catalysts have untapped potential in terms of selectivity in the reduction of a target functionality in multifunctional reactants. This Review provides a comprehensive evalu- ation of the catalytic applications of Au in hydrogenation, assessing the benefits relative to conventional transition metal (e.g. Pt, Pd and Ni) catalytic systems. Hydrogena- tion activity requires the formation of nanoscale Au par- ticles that are (typically) anchored to oxide supports. The crucial catalyst structural and surface properties required to achieve enhanced hydrogenation performance in terms of rate, selectivity and stability are discussed. The syn- thesis procedures and characterisation methodologies directed at catalyst optimisation are evaluated. The prac- tical application of Au catalysts is illustrated taking, as a case study, the hydrogenation of nitroaromatics, where critical features such as hydrogen adsorption/activation, structure sensitivity, metal–support interactions and active site characteristics are discussed. Commonality with the catalytic action of supported Ag is flagged with a consideration of the future outlook and direction for selective hydrogenation using Au catalysts. Introduction/scope Chemical processing is undergoing a progressive redefini- tion in response to increasing restrictions imposed by environmental legislation. As a result, there is now a pressing demand for the development of alternative cleaner routes to target products. Green chemistry is essential for sustainability where catalysis is established as a funda- mental tool [1]. Any step change in catalysis in the twenty- first century must be directed at achieving maximum selectivity to high value products in order to optimise reactant consumption and minimise separation operations and disposal of unwanted by-products [2]. It is now accepted that selectivity to key functionalities rather than reactant turnover is more challenging to achieve and con- trol. Catalytic behaviour can be tuned by modifying (i) the nature of the catalyst or (ii) reaction conditions, notably pressure and temperature. In this Review, we focus on the first alternative and examine rational catalyst design to deliver optimum chemoselectivity for reaction over gold. The work of Haruta et al. [3] dating from 1987 is widely credited for the renaissance of gold as a catalytically active material where, at that juncture, it was considered inactive. Haruta established CO oxidation activity for supported Au nanoparticles at sub-ambient temperatures. Bond [4], however, has unveiled a rich and varied literature that predates Haruta’s work and which demonstrated the cata- lytic properties of gold. The work conducted over the past two decades has established catalytic potential to the point that The World Gold Council has identified ‘catalysis’ as a priority growth area in the technological application of F. Ca ´rdenas-Lizana Group of Catalytic Reaction Engineering, Ecole Polytechnique Fe ´de ´rale de Lausanne (GGRC-ISIC-EPFL), 1015 Lausanne, Switzerland M. A. Keane (&) Chemical Engineering, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, Scotland, UK e-mail: M.A.Keane@hw.ac.uk 123 J Mater Sci DOI 10.1007/s10853-012-6766-7