| 1. |
- Johansson, Wilhelm, et al.
(författare)
-
Transparent TiO2 and ZnO Thin Films on Glass for UV Protection of PV Modules
- 2020
-
Ingår i: American Ceramic Society Bulletin. - 0002-7812 .- 1945-2705. ; 99:4, s. 26-29
-
Tidskriftsartikel (populärvet., debatt m.m.)abstract
- Failure of photovoltaic modules frequently occurs as a result of degradation of their encapsulation material by destructive UV radiation. Transparent TiO2 and ZnO thin films could protect against these harmful wavelengths.
|
|
| 2. |
- Johansson, Wilhelm, et al.
(författare)
-
Transparent TiO2 and ZnO Thin Films on Glass for UV Protection of PV Modules
- 2019
-
Ingår i: Frontiers in Materials. - Lausanne, Switzerland : Frontiers Media S.A.. - 2296-8016. ; 6
-
Tidskriftsartikel (refereegranskat)abstract
- Failure of PV modules frequently occurs as a result of degradation of their encapsulation material by destructive UV radiation. Both the life expectancy and efficiency of PV modules can be improved by reducing the transmittance of the destructive UV radiation through the cover glass without compromising the transmittance in the visible wavelength region. In addition, if the absorbed UV photons can be down-shifted to wavelengths that can be more efficiently converted to electrical energy, an additional increase of the PV efficiency could be achieved. In this study we have investigated transparent ZnO and TiO2 thin films deposited by spray pyrolysis on soda lime silicate float glass as functional layers on PV cover glass. The optical bandgap, UV-cutoff, UV-Vis transmittance, reflectivity (total and diffuse) and photoluminescence have been determined. The ZnO coating shifted the optical bandgap to longer wavelengths, resulting in a reduction of the transmittance of destructive UV radiation by up to ∼85%. Distinct photoluminescence peaks at 377 nm and at 640 nm were observed for one of the ZnO samples. The TiO2 coated glasses also showed an increased UV cutoff, which resulted in a reduction of transmittance of destructive UV radiation by up to 75%. However, no photoluminescence peaks could be observed from the TiO2 films with 325 nm excitation laser, which can be explained by the fact that only indirect interband transitions are accessible at this excitation wavelength. Deposition of both ZnO and TiO2 coatings resulted in a reduction of the transmitted light convertible by PV modules, by up to 12.3 and 21.8%, respectively. The implication of the results is discussed in terms of lifetime expectancy and efficiency of PV modules.
|
|
| 3. |
- Bring, Torun, et al.
(författare)
-
Potassium sulfate droplets and the origin of turbidity in alabaster glass
- 2006
-
Ingår i: Glass Technology : European Journal of Glass Science and Technology A. ; 47:1, s. 15-18
-
Tidskriftsartikel (refereegranskat)abstract
- A study of the criteria required to manufacture multi-component semi-transparent silicate glasses, so called “alabaster” glass, has found that the optical effect is caused by non-crystal¬line potassium sulfate droplets. The droplets were characterized by use of XRD, SEM/EDX and Raman spectroscopy. The size range of the particles is in the order of 5-50 micrometers. It was found that the droplets consisted of potassium sulfate, even if other sulfate compounds were added to the glass. The amount of sulfate compound added, the melting temperature of the furnace and the melting time have significant effect on the optical density of the glass. The optical density of the glass can be correlated to the calculated surface tension of the host glass, suggesting that phase separation of a sulfate enriched liquid phase is part of the mecha¬nism forming the droplets. By adding pigments several different colours can be obtained, but the alabaster effect is not achieved during reducing conditions, thus it seems not possible to produce colours originating from reduced pigments. Pigments tested were Cr, Fe, Co, Cu, Au, Mo/Se, Nd and Ti/Ce/Se.
|
|
| 4. |
- Bring, Torun, et al.
(författare)
-
Selenium : molybdenum-based coloration of alkali silicate glasses
- 2007
-
Ingår i: Glass Technology. - : Society of Glass Technology. - 0017-1050. ; 48:5, s. 213-221
-
Tidskriftsartikel (refereegranskat)abstract
- The interaction between selenium and molybdenum in reduced alkali silicate melts, resulting in red glasses has been studied. The oxidation state of Mo is Mo(VI) as evidenced by XANES and ESCA results. Selenium is present in a reduced state, as indicated by ultraviolet/visible spectroscopy and XANES. The colour is described by ultraviolet/visible spectra and CIE colour coordinates. The main absorption peaks are at 450 and 540 nm. Similar bands are reported for MoOSe32−. Several commonly used glass components must be avoided in the batch, as they prevent formation of the red colour.
|
|
| 5. |
|
|
| 6. |
- Johansson, Wilhelm, et al.
(författare)
-
Transparent TiO2 and ZnO Thin Films on Glass for UV Protection of PV Modules
- 2020
-
Ingår i: American Ceramic Society Bulletin. - : American Ceramic Society Inc.. - 0002-7812 .- 1945-2705. ; 99:4, s. 26-29
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- To stabilize the global temperature and mitigate climate change, the emission of anthropogenic greenhouse gases will have to be greatly reduced. To make it possible, the energy sector will have to transfer from fossil energy to environmentally friendly and carbon neutral sources.
|
|
