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Solar cells using dyes or perovskites as light harvesters supported by mesoscopic oxide films have emerged as credible contenders to conventional p-n junction photovoltaic devices. Separating light absorption from charge carrier transport, dye sensitized mesoscopic solar cells (DSCs) were the first to use a three-dimensional nanocrystalline junction for solar electricity production. From the photon-excited state, charge carriers need to be separated at an electron, and hole acceptor interfaces. Both conditions can be realized with a mesoporous structure made by an electron acceptor material (e.g. TiO2), and spiro-OMeTAD as hole acceptor. It is paramount that charges flow selectively to the desired electrodes without significant recombination. Therefore, electron and hole blocking layers are used in front of the electrodes. However efficient charge transfer into these materials depends on the charge injection properties at their interfaces. Recently, it was shown that the light absorbing methyl ammonium lead iodide perovskite material (CH3NH3PbI3) exhibit ambipolar charge transport character. And using CH3NH3PbI3 perovskite as an absorber layer and spiro-OMeTAD or poly tertiary aryl amine (PTAA) as a hole transport material, power conversion efficiencies (PCE) over 17% were obtained. 3-5 Remarkably, however, the cell has an absorbing CH3NH3PbI3 perovskite layer as thin as only 300 nm; yet it achieves a short circuit current over 21 mA/cm2, an open circuit voltage as high as 1.1 V. This performance is comparable to the best single crystal GaAs thin-film solar cell and outperforms all current high-efficiency polycrystalline thin-film solar cells based on chalcogenide absorbers such as Cu(In,Ga)Se2, CdTe, and Cu2ZnSn(Se,S)4. In this talk we present various deposition methods for perovskite absorbing layer, and the synthesis and characterization of novel hole transporting materials.

Speaker

Md. K. Nazeeruddin , Professor at EPFL, Switzerland , who has published over 450 in peer reviewed scientific publications, 10 review/invited book chapters and inventor or co-inventor of 45 patents, with an h index of 92, and total citations of 36000. He is an expert in Dye-sensitized Solar Cells, Perovskite Solar Cells and Organic Light Emitting Diodes and appeared in the ISI listing of most cited chemists. He has recieved numerous rewards for research excellence.