CHEMICAL ENGINEERING TRANSACTIONS VOL. 47, 2016 A publication of The Italian Association of Chemical Engineering Online at www.aidic.it/cet Guest Editors: Angelo Chianese, Luca Di Palma, Elisabetta Petrucci, Marco Stoller Copyright © 2016, AIDIC Servizi S.r.l., I SBN 978-88-95608-38-9; I SSN 2283-9216 Synthesis and Characterization of Water Stable ZnO Quantum Dots Based-Sensor for Nitro-Organic Compounds Marcello Casa a *, Maria Sarno a , Lucia Paciello a , Marco Revelli Beaumont b , Paolo Ciambelli a a Department of Industrial Engineering and Centre NANO_MATES University of Salerno Via Giovanni Paolo II ,132 - 84084 Fisciano (SA), Italy b Université Paul Sabatier, 118 Route de Narbonne, 31062 Toulouse Cedex 4, France mcasa@unisa.it Here we propose luminescent ZnO QDs synthesized by a simple method in an unusual, powerful and ‘green’ solvent at low temperature, for the detection of aniline (e.g. 4-nitroanilina) compounds in water environment. To provide aqueous stability, ZnO QDs have been capped by (3-aminopropyl)triethoxysilane (APTES). The synthesized ZnO QDs have been characterized using X-ray diffraction, Transmission Electron Microscopy, Raman, UV-visible, Photoluminescence and Infrared Spectroscopy. This study demonstrates that the as synthesized ZnO QDs are highly luminescent, emitting yellow colour when exposed to UV radiation. Under UV radiation the nanoparticles exhibit high sensitivity to the presence of nitro-compounds in solution when they have a zwitterionic structure, even at very low concentration. In particular, this property makes APTES capped ZnO QDs very effective as sensor for p-nitroaniline. 1. Introduction Zinc oxide (ZnO) is a white inorganic compound insoluble in water, and the bulk form is widely used as additive in rubbers, plastics, ceramics, glass, cement, lubricants, paints, ointments, adhesives, sealants, pigments, foods, batteries, ferrites, fire retardants, and first-aid tapes (Kołodziejczak-Radzimska and Jesionowski, 2014). In the last years, the synthesis of zinc oxide structures with nano dimension, for example nanorods, nanowires, tetrapods and nanoparticles, has been reported (Xu and Wang, 2011). When ZnO dimensions shrink in the nano domain the material gains new and remarkable physical, antimicrobial and optoelectronic properties that can be useful for electronic, sensoring and biosensoring, spintronic, piezoelectronic applications (Vladimir A Fonoberov, 2006). Among its application, ZnO can be combined with gallium nitride for LED (Bakin et al., 2010), it is the most promising candidate in the field of random lasers to produce an electronically pumped UV laser source (Lu et al., 2015), it is already been used in form of nanorods for gas sensoring of dangerous species like H2 and CO (Idriss and Barteau, 1992) and is usually used as field emitter (Li et al., 2004). Moreover, ZnO quantum dots (namely nanoparticles of diameter of the order of some nanometers) show strong luminescence and have emerged as a new class of strong fluorescent sensors (Bera et al., 2008). Singh (2012) has studied the effect of ammonia gas on the emission of ZnO decorated luminescent graphene. Various aromatic aldehydes have been selectively detected by Jana (2005) using ZnO QDs. Sharma (2013) have fabricated imine linked ZnO QDs for the detection of Co 2+ ions. Mg 2+ ion sensor has been successfully fabricated using ZnO QDs capped with Schiff base (Sharma et al., 2012). In the last decades, the increasing use of noxious compounds led to devastating effect not only for the environment but also for human health (Kutz et al., 1992). Among various organic and inorganic pollutants, aniline derivatives (e.g. nitroanilines) are suspected carcinogens and are highly toxic to aquatic life. They are toxic by inhalation, in contact with skin and if swallowed. In particular, it has been demonstrated that p- nitroaniline causes methemoglobinemia (B S Kulkarni, 1969), chronic cumulative liver damage (OSHA), and eventually dead (A. Bakdash, 2006). Nevertheless, p-nitroaniline and the other aniline derivatives are widely DOI: 10.3303/CET1647002 Please cite this article as: Casa M., Sarno M., Paciello L., Revelli Beaumont M., Ciambelli P., 2016, Synthesis and characterization of water stable zno quantum dots based-sensor for nitro-organic compounds, Chemical Engineering Transactions, 47, 7-12 DOI: 10.3303/CET1647002 7