Photoinduced energy transfer in a CdTe quantum dot-copper phthalocyanine system via two-photon excitation

Photoinduced process in CdTe quantum dots (QDs)-copper phthalocanine (CuPc) non-conjugated system via two-photon excitation has been investigated by time-correlated single photon counting techniques with femtosecond laser pulse. Efficient energy transfer in the CdTe-CuPc system via two-photon excitation was observed. The energy transfer efficiency was found to decrease with an increase in excitation laser power, and the maximum energy transfer efficiency can reach 43.8% via two-photon excitation. This work indicates that the QD-phthalocyanine system has potential applications in two-photon-excitation photodynamic therapy.