UV/Vis Spectroscopy
UV-Vis spectroscopy is an analytical technique that is able to measure the amount of distinct wavelengths of visible light that are absorbed by and/or transmitted through a sample of choice. In other words, how much light a substance is able to absorb. In a sampled cuvette, there is a linear relationship between how much light is absorbed “A” and the concentration “C” of the absorbing sample. This relationship is called the Beer’s law. Other factors in the law are the path length “D” and a factor called the extinction coefficient “E” which is specific to each substance. In addition though, the absorbance value “A” is inversely proportional to T which is the light transmitted through the sample which plays a vital role.
In the diagram blow, we have a block diagram of a typical instrumental set-up for a UV/Vis spectrometer. Inside the spectrometer a lamp directs a beam of light through the cuvette. The sample in the cuvette absorbs particular wavelengths better than others and the light that isn't absorbed becomes the transmitted light. This light passes through the cuvette and is then diffracted by a grating or various filters onto the detector.
Linked below is a extremely cheap and easy way to built a "At Home Spectrometer", only involving common tools and can be done anywhere.
Additionally, below is experimental use of UV/Vis in my research work with metal-organic frameworks (MOF). Here, we used the UV/Vis spectrometer to gather photodegradation data on UIO-66-NH2 Ce-substituted to determine if our MOF is absorbing the energy from the light! Use the tabs at the bottom to sort through pages. (Full data available upon request).
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