Cadmium plays a significant role in the creation of pigments, particularly cadmium yellow, cadmium red, cadmium orange, and cadmium green. Cadmium green, however, is not a pure cadmium pigment but a mixture of cadmium yellow with a blue pigment, such as phthalocyanine blue. These pigments are based on two primary compounds: cadmium sulfide and cadmium selenide. This lesson explores the composition and XRF analysis of cadmium pigments.
Objectives
- Identify the key cadmium-based pigments and their compositions.
- Interpret the XRF spectra of cadmium pigments, including cadmium yellow and cadmium red.
Materials
- Pigments Checker STANDARD containing cadmium yellow, cadmium red, and cadmium green.
Lesson Plan
- Introduction to Cadmium Pigments
- Discuss the primary cadmium pigments: yellow, and red.
- Explain the chemical compositions of the main cadmium pigments components: cadmium sulfide (CdS), cadmium selenide (CdSe), and zinc sulfide (ZnS).
- XRF Spectra of Cadmium Yellow
- Analyze the XRF spectrum of cadmium yellow.
- Identify zinc peaks as expected from its formula.
- XRF Spectra of Cadmium Red
- Examine the XRF spectrum of cadmium red.
- Note the presence of selenium peaks instead of zinc peaks.
