Periodically perforated aluminum film for enhancing chemiluminescence

The influence of a thin periodically perforated aluminum film on the rate of radiative relaxation of excited luminol molecules was investigated. Numerical modeling showed that an aluminum film with a thickness of 20 nm and cylindrical holes with a radius of 36 nm, arranged in a square lattice with a period of 230 nm, accelerates the chemiluminescence of luminol at a wavelength of 430 nm. The acceleration of radiative transitions and the corresponding increase in chemiluminescence intensity exceed 10 times in most of the volume of the nanohole and are weakly dependent on the position of the emitting molecule and the orientation of the transition dipole moment.