Abstract
Photoexcited states of NH4BPh4 (TPhBA) particles embedded in mesoporous frameworks of different pore sizes were studied by combined electron paramagnetic resonance (EPR), optical and photoluminescence techniques. A distribution of triplet states with short and long electron–hole distances was found. While EPR studies on TPhBA bulk sample suggested that the formation of electron–hole pairs upon the excitation was caused by electron capture on electron traps, the samples in mesoporous frameworks exhibit two ways of the pair formation. The first one is attributed to the capture on phenyl rings and another one is to be thought as the capture of electrons on adsorbed oxygen molecules. These results are also consistent with the thermoluminescence spectra and EPR studies of the photoexcited samples during annealing.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
