The diffuse reflection measurements were performed using a Spectralon® coated integration sphere, placed in an Edinburgh Instruments FS920 spectrometer. The samples were irradiated between 200 and 300 nm, whereby the radiation was generated by a 450 W xenon arc lamp. The spectrometer contained two TMS300 monochromators with 1800 F/mm gratings and a photomultiplier tube R928 (Hamamatsu). The photomultiplier tube was cooled to −20 °C by Peltier elements. To calculate the reflectivity of the powder samples, a white standard material was needed. For this purpose, BaSO4 (99.99%, Sigma-Aldrich) powder was used.
The emission spectra were recorded by using an Edinburgh Instruments FLS920 spectrometer equipped with an ozone generating 450 W xenon arc lamp and a single-photon-counting photomultiplier tube (Hamamatsu R928) which was cooled down to −20 °C. As recorded, the emission spectra were corrected by applying a correction file obtained from a calibrated tungsten incandescent lamp certified by the National Physical Laboratory (NPL).
To determine the filter efficiency, the coated glass slides were fixed in front of a Spectralon® coated integration sphere, mounted inside an Edinburgh Instruments FS920 spectrometer. The samples were irradiated with a bare Ushio Care222 lamp (i.e. dichroic filter removed) and the transmitted light was detected by a photomultiplier tube R928 (Hamamatsu).
The emission spectra were recorded by using an Edinburgh Instruments FLS920 spectrometer equipped with an ozone generating 450 W xenon arc lamp and a single-photon-counting photomultiplier tube (Hamamatsu R928) which was cooled down to −20 °C. As recorded, the emission spectra were corrected by applying a correction file obtained from a calibrated tungsten incandescent lamp certified by the National Physical Laboratory (NPL).
To determine the filter efficiency, the coated glass slides were fixed in front of a Spectralon® coated integration sphere, mounted inside an Edinburgh Instruments FS920 spectrometer. The samples were irradiated with a bare Ushio Care222 lamp (i.e. dichroic filter removed) and the transmitted light was detected by a photomultiplier tube R928 (Hamamatsu).