Study of Cage Effect under Photolysis in Polymer Matrices by Flash Photolysis (CAT#: STEM-ST-0316-WXH)

Flash photolysis is a pump-probe laboratory technique, in which a sample is first excited by a strong pulse of light from a pulsed laser of nanosecond, picosecond, or femtosecond pulse width or by another short-pulse light source such as a flash lamp. This first strong pulse is called the pump pulse and starts a chemical reaction or leads to an increased population for energy levels other than the ground state within a sample of atoms or molecules. Typically the absorption of light by the sample is recorded within short time intervals (by a so-called test or probe pulses) to monitor relaxation or reaction processes initiated by the pump pulse.

Used to study light-induced processes in organic molecules, polymers, nanoparticles, semiconductors, photosynthesis in plants, signaling, and light-induced conformational changes in biological systems.

The process of laser flash photolysis can be divided into three steps: absorption, excitation and decomposition.
First, when the laser beam hits the surface of the material, the photons will be absorbed by the material, making the material molecules or atoms in an excited state.
Then, the material molecules or atoms in the excited state will transition to a lower energy level state through spontaneous emission or excitation by external photons.
Finally, the molecules or atoms of matter will release energy during the transition process, which will break down into smaller molecules or atoms.

Flash Photolysis Spectrometer