Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5451639 | Journal of Materials Science & Technology | 2016 | 38 Pages |
Abstract
3d transition metal oxides based thin film coatings such as copper-cobalt oxides exhibit high absorption in the visible region and low emittance in the infrared to far-infrared region of the solar spectrum which is favourable for use as potential selective surface materials in photothermal devices. These materials have the potential to minimize heating while increasing absorption in the operative spectrum range and therefore achieve higher solar selectivity. A series of mixed copper-cobalt metal spinel oxides (CuxCoyOz) doped with graphene oxide thin films were deposited on commercial grade aluminium substrates using a sol-gel dip-coating technique at an annealing temperature of 500â°C in air for 1âh. Characterizations of the synthesized films were carried out by high temperature synchrotron radiation X-ray Diffraction (SR-XRD), UV-Vis, Fourier Transform infrared spectroscopy (FTIR) and X-ray photoelectron microscopy (XPS) techniques. High thermal stability of coatings with multiple phases, binary and ternary metal oxides, was defined through SR-XRD study. FTIR analysis shows moderate (<80%) to high (up to 99%) reflectance in the infrared region while the UV-Vis investigations demonstrate that, in the visible region, solar absorption increases gradually (up to 95%) with the addition of graphene oxide to the CuxCoyOz coatings. With the incorporation of 1.5 wt.% of graphene oxide to the copper-cobalt oxide coatings, a high solar selectivity of 29.01 (the ratio of the average solar absorptance in visible and the average thermal emittance in infrared to far infrared region; α/ε) was achieved.
Keywords
Related Topics
Physical Sciences and Engineering
Materials Science
Materials Chemistry
Authors
M. Mahbubur Rahman, Zhong-Tao Jiang, Chun-Yang Yin, Lee Siang Chuah, Hooi-Ling Lee, Amun Amri, Bee-Min Goh, Barry J. Wood, Chris Creagh, Nicholas Mondinos, Mohmmednoor Altarawneh, Bogdan Z. Dlugogorski,