Plasma-assisted synthesis of Ag/ZnO nanocomposites: First example of photo-induced H 2 production and sensing Quentin Simon a , Davide Barreca b, *, Daniela Bekermann a , Alberto Gasparotto a , Chiara Maccato a , Elisabetta Comini c , Valentina Gombac d , Paolo Fornasiero d , Oleg I. Lebedev e , Stuart Turner f , Anjana Devi g , Roland A. Fischer g , Gustaaf Van Tendeloo f a Department of Chemistry, Padova University and INSTM, 35131 Padova, Italy b CNR-ISTM and INSTM, Department of Chemistry, Padova University, 35131 Padova, Italy c CNR-IDASC, SENSOR Lab, Department of Chemistry and Physics, Brescia University, 25133 Brescia, Italy d Department of Chemical and Pharmaceutical Sciences, Trieste University, INSTM and ICCOM Trieste Research Unit, 34127 Trieste, Italy e Laboratoire CRISMAT, UMR 6508, CNRS-ENSICAEN, 14050 Caen CEDEX 4, France f EMAT, Antwerp University, 2020 Antwerpen, Belgium g Lehrstuhl fu ¨ r Anorganische Chemie II, Ruhr-University Bochum, 44780 Bochum, Germany article info Article history: Received 26 July 2011 Received in revised form 1 September 2011 Accepted 12 September 2011 Available online 6 October 2011 Keywords: ZnO Ag PE-CVD RF-Sputtering Hydrogen production Hydrogen sensing abstract Ag/ZnO nanocomposites were developed by a plasma-assisted approach. The adopted strategy exploits the advantages of Plasma Enhanced-Chemical Vapor Deposition (PE-CVD) for the growth of columnar ZnO arrays on Si(100) and Al 2 O 3 substrates, in synergy with the infiltration power of the Radio Frequency (RF)-sputtering technique for the subsequent dispersion of different amounts of Ag nanoparticles (NPs). The resulting composites, both as-prepared and after annealing in air, were thoroughly characterized with particular attention on their morphological organization, structure and composition. For the first time, the above systems have been used as catalysts in the production of hydrogen by photo-reforming of alcoholic solutions, yielding a stable H 2 evolution even by the sole use of simulated solar radiation. In addition, Ag/ZnO nanocomposites presented an excellent response in the gas-phase detection of H 2 , opening attractive perspectives for advanced technological applications. Copyright ª 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved. 1. Introduction The importance of hydrogen as an appealing energy vector, due to its high efficiency and environment-friendly combus- tion, is nowadays well recognized and documented [1e5]. Nevertheless, in spite of several research activities in this field, the large-scale production and detection of H 2 , an odorless, colorless and flammable gas, are still challenging issues in view of the eventual transition to an H 2 -based economy [6]. To this regard, the development of materials capable of acting as multi-functional platforms for the sustainable generation and sensing of hydrogen, though rep- resenting a strategic target, is still far from being completely satisfied [7,8]. Among the possible candidates, ZnO, a n-type semi- conductor (E g ¼ 3.4 eV) that can be synthesized with diverse morphologies [9], has been the object of several studies regarding photocatalysis and gas sensing utilization [10]. The * Corresponding author. Tel.: þ39 (0) 498275170; fax: þ39 (0) 498275161. E-mail address: davide.barreca@unipd.it (D. Barreca). Available online at www.sciencedirect.com journal homepage: www.elsevier.com/locate/he international journal of hydrogen energy 36 (2011) 15527 e15537 0360-3199/$ e see front matter Copyright ª 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.ijhydene.2011.09.045