Manipulation Of The Energy Transfer Dynamics Between Quantum Dots And Graphene Oxide

The investigation of energy transfer dynamics between donor quantum dots(QDs)and acceptor molecules is important in applications in photodetectors,optoelectronic devices,light-emitting diodes,and solar cells.In recent years,combining QDs and graphene oxide(GO)has attracted widespread attentions.In order to improve the efficiency of photoelectric conversion,it is necessary to study the interaction of photoexcited carriers in nanostructures and manipulate the progress of energy transfer between them.In this work,the energy transfer dynamics between QDs and different reduced degrees GO were studied by using time-resolved spectroscopy based on pump-probe technique.We have studied the photoluminescence and excited state characteristics of QDs by measuring the transient spectroscopy.With the reduced GO by laser irradiation,it is found that there occurs the change in transient spectrum of QDs and GO,and the interaction between them is further understood.We analyzed the dynamic behavior between QDs and GO,including fluorescence resonance energy transfer and exciton energy transfer.The efficiently manipulation of energy transfer between them can provide technical support for the preparation of related optoelectronic devicesThe main work in this paper focus on the absorption,excitation and emission spectra of colloidal quantum dots,the transient spectra of QDs and different reduced degrees GO.The energy transfer dynamics between QDs and different reduced degrees GO were studied.The interaction mechanism of excited state between the QDs and GO was analyzed,then the energy transfer process between them was effectively controlled.The main innovations of this article are:1.By measuring the transient spectroscopy based on pump-probe technique,we study the exciton energy transfer and fluorescence resonance energy transfer dynamic between QDs and GO were observed.2.We have detected the transient absorption spectra of QDs during the GO were reduced by laser.The exciton bleaching signal presents different time scales at long wavelength and short wavelength with the laser irradiation time increased,and the intensity also changes,which can be attributed to the excition energy transfer between QDs and GO.With the GO were reduced gradually,the stimulated emission signal of QDs will be quenched,and then the excited state absorption signal of QDs will also disappear,owing to the fluorescence resonance energy transfer.3.Adjusting energy band structure of GO by changing the reduced degree of GO,the energy transfer process of QDs and GO can be effectively controlled,which provides technical support for the preparation of related optoelectronic devices.