We report for the first time on a hole conductor-free mesoscopic methylammonium lead iodide (CH 3NH 3PbI 3) perovskite/TiO 2 heterojunction solar cell, produced by deposition of perovskite nanoparticles from a solution of CH 3NH 3I and PbI 2 in γ-butyrolactone on a 400 nm thick film of TiO 2 (anatase) nanosheets exposing (001) facets. A gold film was evaporated on top of the CH 3NH 3PbI 3 as a back contact. Importantly, the CH 3NH 3PbI 3 nanoparticles assume here simultaneously the roles of both light harvester and hole conductor, rendering superfluous the use of an additional hole transporting material. The simple mesoscopic CH 3NH 3PbI 3/TiO 2 heterojunction solar cell shows impressive photovoltaic performance, with short-circuit photocurrent J sc= 16.1 mA/cm 2, open-circuit photovoltage V oc = 0.631 V, and a fill factor FF = 0.57, corresponding to a light to electric power conversion efficiency (PCE) of 5.5% under standard AM 1.5 solar light of 1000 W/m 2 intensity. At a lower light intensity of 100W/m 2, a PCE of 7.3% was measured. The advent of such simple solution-processed mesoscopic heterojunction solar cells paves the way to realize low-cost, high-efficiency solar cells. © 2012 American Chemical Society.
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledged KAUST grant number(s): KUS- C1-015-21
Acknowledgements: The authors thank Carole Graetzel for fruitful discussions. This work was partially supported by EU FP7 project ENERGY-261920 "ESCORT". M.K.N. thanks the World Class University program, Photovoltaic Materials, Department of Material Chemistry, Korea University, Chungnam, 339-700, Korea, funded by the Ministry of Education, Science and Technology through the National Research Foundation of Korea (No. R31-2008-000-10035-0). FP7-NMP-2009 Project SANS under the contract No. NMP-246124, and ORION grant agreement number NMP-229036. The Research was partially supported by the King Abdullah University of Science and Technology (KAUST, Award No KUS- C1-015-21).
This publication acknowledges KAUST support, but has no KAUST affiliated authors.