Electrical and thermal properties of a carbon nanotube/polycrystalline BiFeO3/Pt photovoltaic heterojunction with CdSe quantum dots sensitization

Electrical and thermal properties of a carbon nanotube (CNT)/multiferroic BiFeO3 (BFO)/Pt photovoltaic heterojunction are investigated for the first time. Enhanced photovoltaic properties (Jsc ≈ 2.1 μA cm−2 and Voc ≈ 0.47 V), as compared to the traditional polycrystalline BFO with indium tin oxide (ITO) as the top electrode, are observed due to the unique properties of CNT. An equivalent electrical and thermal model is constructed based on the energy band diagram of the CNT/BFO/Pt heterojunction for the first time and the carriers' transportation behavior is depicted theoretically. The influence of CdSe quantum dots (QDs) sensitization on the photovoltaic properties is presented, and a clear improvement of ∼4 fold in photocurrent density is observed.