Related Experiment Video
Updated: Oct 4, 2026

Phase-Dependent Control of Trap Depth and Persistent Luminescence in Strontium Aluminate Phosphors
Published on: December 5, 2025
Room-temperature luminescence from kaolin induced by organic amines
L M Coyne1, G Pollack, R Kloepping
1Department of Chemistry, San Jose State University, California 95192, USA.
Abstract:
Several new, room-temperature luminescent phenomena, resulting from the interaction of kaolin and various amino compounds, have been observed. The emission of light from kaolin pastes (treated with quinoline, pyridine, hydrazine, monoethanolamine, n-butylamine, and piperidine) was shown to decay monotonically over a period of hours to days. More light was released by a given amino compound after it was dried and purified. Hydrazine, in addition to the monotonically decaying photon release, produces delayed pulses of light with peak emission wavelength of 365 nm which last between several hours and several days. These photon burst are acutely sensitive to the initial dryness of the hydrazine, both in the number of bursts and the integrated photon output. The amount of light and the capacity of the kaolin to produce the delayed burst appeared to be strongly dependent on preliminary heating and on gamma-irradiation, analogous to the dehydration-induced light pulse previously reported from the Ames Research Center. A small, delayed burst of photons occurred when piperidine and n-butylamine were removed by evaporation into an H2SO4 reservoir.
Related Concept Videos
Photoluminescence: Applications
Variables Affecting Phosphorescence and Fluorescence
Flame Photometry: Lab
Physical Properties of Amines
Atomic Spectroscopy: Effects of Temperature
At thermal equilibrium, the relative populations of excited and ground state atoms can be estimated using the Maxwell–Boltzmann distribution. For example, an increase in temperature from...

