Conversion of amorphous TiO2 coatings into their crystalline form using a novel microwave plasma treatment |
| |
| Authors: | Binh HQ Dang Mahfujur Rahman Don MacElroy Denis P Dowling |
| |
| Affiliation: | 1. School of Chemical & Bioprocess Engineering, University College Dublin, Ireland;2. School of Mechanical & Materials Engineering, University College Dublin, Ireland;1. Department of Physics, Aligarh Muslim University, Aligarh 202002, India;2. Centre of Excellence in Materials Science (Nanomaterials), Department of Applied Physics, Z.H. College of Engineering & Technology, Aligarh Muslim University, Aligarh 202002, India;1. Technische Universität Berlin, Institut für Werkstoffwissenschaft, Englische Strasse 20, D-10587 Berlin, Germany;2. Humboldt Universität Berlin, Institut für Physik, Newtonstrasse 15, D-12489 Berlin, Germany;3. Technische Universität Berlin, Institut für Chemie, Strasse des 17. Juni 124, D-10623 Berlin, Germany;1. College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter EX4 4QL, UK;2. School of Materials Science and Engineering, Nanchang Hangkong University, Nanchang 330063, China;3. College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387, China;4. Mechanical and Nuclear Engineering Department, Kansas State University, Manhattan, KS, 66506, USA;1. School of Physics, Universiti Sains Malaysia, 11800, Penang, Malaysia;2. Chemistry Section, School of Distance Education, Universiti Sains Malaysia, 11800, Penang, M, alaysia;3. Electrochemistry Laboratory, Physical Chemistry Department, National Research Centre, P.O. 12622, Dokki, Giza, Egypt |
| |
| Abstract: | Crystalline titanium dioxide (TiO2) coatings have been widely used in photo-electrochemical solar cell applications. In this study, TiO2 and carbon-doped TiO2 coatings were deposited onto unheated titanium and silicon wafer substrates using a DC closed-field magnetron sputtering system. The resultant coatings had an amorphous structure and a post-deposition heat treatment is required to convert this amorphous structure into the photoactive crystalline phase(s) of TiO2. This study investigates the use of a microwave plasma heat treatment as a means of achieving this crystalline conversion. The treatment involved placing the sputtered coatings into a 2.45 GHz microwave-induced nitrogen plasma where they were heated to approximately 550 °C. It was observed that for treatment times as short as 1 min, the 0.25-μm thick coatings were converted into the anatase crystalline phase of TiO2. The coatings were further transformed into the rutile crystalline phase after treatments at higher temperatures. The doping of TiO2 with carbon was found to result in a reduction in this phase transformation temperature, with higher level of doping (up to 5.8% in this study) leading to lower anatase-to-rutile transition temperature. The photoactivity performance of both doped and un-doped coatings heat-treated using both furnace and microwave plasma was compared. The carbon-doped TiO2 exhibited a 29% increase in photocurrent density compared to that observed for the un-doped coating. Comparing carbon-doped coatings heat-treated using the furnace and microwave plasma, it was observed that the latter yielded a 19% increase in photocurrent density. This enhanced performance may be correlated to the differences in the coatings' surface morphology and band gap energy, both of which influence the coatings' photoabsorption efficiency. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
