Binding and decomposition of organic dye molecules on ZnO crystals |
| |
| Affiliation: | 1. Kombolcha Institute of Technology, Wollo University, Kombolcha, P.O.box. 208, Ethiopia;2. Department of Civil and Environmental Engineering, Addis Ababa University, Addis Ababa Institute of Technology, Addis Ababa, Ethiopia;1. BAM, Bundesanstalt für Materialforschung und -prüfung, Unter den Eichen 87, 12205 Berlin, Germany;2. Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37934, USA;3. Mechanical Engineering Department, University of Connecticut, Storrs, CT 06238, USA;4. Technical University Berlin, Institute for Materials, Fasanenstr. 90, 10623 Berlin, Germany;5. Thermo Fisher Scientific, Takustr. 7, 14195 Berlin, Germany;6. Reliability Division, Rolls Royce LG Fuel Cell System Inc., North Canton, OH 44720, USA;7. University of Potsdam, Institute of Physics and Astronomy, Karl-Liebknecht-Str.24-25, 14476 Potsdam, Germany;1. College of Chemistry and Chemical Engineering, Hunan Institute of Science and Technology, Yueyang 414006, China;2. College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China;3. College of Automotive Engineering, Hunan Industry Polytechnic, Changsha 410007, China;1. Université de Picardie Jules Verne, AGIR, UFR de Pharmacie, Amiens, UR, 4294, France;2. Université Aix-Marseille, IRD, AP-HM, SSA, VITROME, IHU Méditerranée Infection, Marseille, France;3. CNRS, Univ. Bordeaux, Bordeaux INP, ICMCB, UMR 5026, F- 33600 Pessac, France;4. Université de Bordeaux, Laboratoire ARNA, UFR des Sciences Pharmaceutiques, Bordeaux, France;5. INSERM U1212, UMR CNRS 5320, Laboratoire ARNA, Bordeaux, France;6. Unité parasitologie et entomologie, Département de microbiologie et de maladies infectieuses, Institut de recherche biomédicale des armées, Marseille, France;7. Aix-Marseille Univ, IRD, SSA, AP-HM, VITROME, Marseille, France;8. IHU Méditerranée Infection, Marseille, France;9. Unité de Développements Analytiques et Bioanalyse, IRBA, Brétigny-sur-Orge, France;10. Centre national de référence du paludisme, Marseille, France;1. Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH, USA;2. Pharmaceutical Chemistry Department, Faculty of Pharmacy, Helwan University, Cairo, Egypt;3. College of Pharmacy, The Ohio State University, Columbus, OH, USA;4. Department of Chemistry, Virginia Tech, Blacksburg, VA, USA;5. Department of Chemistry, Georgia State University, Atlanta, GA, USA;1. Department of Infectious Diseases, Sterling Hospital, Ahmedabad, 380052, India;2. Division of Infectious Diseases, Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, 33612, USA;3. Infectious Diseases Consultant, 405, AXIS Business Space, Nanpura, Surat, 395001, India;4. Clinical Microbiologist, Abha Laboratory Pvt Ltd, 2nd Floor, Rajratna Chambers, Dabgharwad, Bhagal, Surat, India |
| |
| Abstract: | Prism surfaces of ZnO crystals are prepared by various pretreatments as heating in ultrahigh vacuum (UHV), annealing in oxygen at pressures up to 105 Pa, argon bombardment, cleavage in UHV. An organic dye is deposited by sublimation in UHV and the exposure (1012−1015 cm−2 is recorded by means of a vibrating quartz. Adsorption and desorption studies including thermal desorption spectroscopy (TDS) are performed with variation of crystal temperature during deposition and of coverage. In these experiments the spectral distribution of absorption is used for the recording of coverage down to about 1012 cm−2, for the observation of ordering processes within the dye layer and for the detection of dye decomposition. By the various treatments the catalytic activity of the ZnO surface for decomposition of the dye molecules at temperatures above 350 K can be increased or decreased in a wide range. Possible sources of the activity are discussed. Molecules bound to a clean inactive ZnO surface desorb above 600 K. In contrast they come off already at 350 K if they are bound only to other molecules. A sticking coefficient is derived as a function of coverage at 470 K and compared with calculations after several adsorption models. The best fit is obtained by a precursor state model. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
