Dye molecules in zeolites as artificial antenna

Abstract

When cationic dye molecules are exchanged into the parallel channels of zeolite L, they are so close together that energy transfer can occur. The restricted geometry of the zeolite L channels excludes aggregation and self-quenching even at very high concentration. We report three types of experiments with pyronine and oxonine which indicate that such zeolite-dye arrangements can be used as antenna for light harvesting. First, we show that energy transfer occurs inside the zeolite microcrystals filled with a mixture of both chromophores. This proves that the achieved distance distribution fulfils the conditions imposed by the law of electronic excitation energy transfer. Second, we show that the quanta absorbed by pyronine located inside the zeolite microcrystals can be trapped by an acceptor with the right spectral properties placed on their surface. In a third experiment, we show that in a mixture of zeolite microcrystals loaded with pyronine as donor D and others loaded with oxonine as acceptor A, energy transfer occurs from the D to the A filled particles.