Efficient electron transfer in CdSe quantum dots-decorated reduced graphene oxide for electromagnetic interference shielding application

Effective charge separation and use of hot charge carriers are considered to be the most essential factors affecting the activity of an excellent energy harvester. Herein, we have successfully decorated 3 nm of CdSe quantum dots (QDs) on the surface of reduced graphene oxide (rGO) using solvothermal method. Formation of CdSe–rGO nanocomposite (NC) has been confirmed by X-ray diffraction pattern, transmission electron microscopy and Raman analysis. Further, the emission spectrum of CdSe–rGO NC shows quenching of emission of CdSe QDs on the surface of rGO nanosheet. To elucidate this phenomenon, we have carried out time-correlated single-photon counting (TCSPC) measurements, which reveal efficient electron transfer, as the exciton lifetime of CdSe QDs in the NC is significantly reduced compared to bare CdSe QDs. Owing to the efficient electron transfer, this NC showed big boost in total shielding effectiveness (SE_T = 29 dB) when compared to graphene (SE_T = 23 dB) in electromagnetic interference shielding application.