Real-Time UV/VIS Spectroscopy to Observe Photocatalytic Degradation

Abstract

In this work, we have developed a real-time UV/VIS spectroscopy method using a broadband Xenon Arc lamp to detect photocatalytic reactions in real time. A CMOS camera was used instead of an output slit to capture all spectral information simultaneously, which can enable a real-time detection of the UV/VIS absorption of the analytes within a single frame of the camera. To verify real-time spectroscopy, a wavelength calibration process was performed using three laser line filters and a didymium glass filter sample. To demonstrate that this real-time spectroscopic setup can be used for rapid measurements, MB samples were used to observe the real-time photocatalytic degradation of MB by TiO2 nanoparticles. For real-time measurement, four samples with different TiO2 nanoparticle quantities showed different photocatalytic degradation mechanisms. By plotting the spectra every 20 ms, the series of spectra clearly showed the degradation of MB in real time.