High Pressure Effects on Fluorescence-Quenching of Coumarin 343 Adsorbed on TiO_2 Nanocrystallites in Methanol and in N,N-Dimethylformamide

摘要

The effect of high pressures up to 400 MPa on the emission quenching of Coumarin 343 (C343) adsorbed on TiO_2 nanocrystallites in methanol (MeOH) and N,N-dimethylformamide (DMF) solution was investigated.In MeOH,the quenching efficiency decreased as the pressure increased.This decrease was explained by the decrease of the adsorption strength of C343 onto Tio_2 nanocrystallites.On the contrary,the efficiency in DMF increased with increase of pressure in spite of decrease of adsorption strength of C343 onto TiO_2 under the high pressure condition,indicating enhancement in the electron transfer efficiency.The results imply that the high pressure technique can control the efficiency of photo-induced electron transfer systems