Higher Secondary Education

• V1 Color change to blue of the PBB-solution (water based solution with ethylviologen = substrate, proflavine = photocatalyst and EDTA = sacrificial donor) caused by irradiation with light (blue or white light) and reverse color change caused by shaking in a half-filled and sealed testtube
• V2 PBB in absense of O₂ in a fully filled and sealed testtube
• V3 PBB in an electrochemical measurement setup consisting of two electrolyte-bridged half-cells with an irradiated and a not irradiated PBB-solution (solar battery with half cells)
• V4 Compact cell made of FTO glass, filter paper soaked with PBB-Lösung and razor foils (solar battery as compact cell)
• V5 PBB variations with alternate substrates and photocatalysts
  • Videos with photo redox reactions on the basis of the PBB experiment
  • Worksheets regarding material cycles and energy conversions on the basis of the PBB experiment
  • Article on Variations of the Photo-Blue-Bottle experiments
  • Article containing an education module regarding the carbon cycle in the biosphere (lower secondary education)

Technical Contents

coupled reaction cycles of the substrate and the photocatalyst, light induced reaction cycle of the photocatalyst, photo electron transfer, redox pairs and their redox potentials in the ground and in the excited state, light energy conversion and storage in the reduced substrate, quantitative determination of the substrate conversion; relation: structure-color of the colorless and the colored form of the substrate

Scope

cycle of matter (PBB as model experiments for the cycle photosynthesis-cell respiration);
electro chemistry (redox reactions and -potentials, Nernst equation); catalysis (differentiation between photocatalysis and catalysis); energetics (conversion of radiation energy into chemical bond energy) (higher secondary education); chemistry/biology: PBB and the carbon cycle in the biosphere