Samuel D. Stranks1, Giles E. Eperon1, Giulia Grancini2, Christopher Menelaou1, Marcelo J. P. Alcocer2, Tomas Leijtens1, Laura M. Herz1, Annamaria Petrozza2, Henry J. Snaith1
1University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, UK
2Center for Nano Science and Technology @PoliMi, Istituto Italiano di Tecnologia, Via Giovanni Pascoli 70/3, 20133 Milano, Italy
Tóm tắt
Unrestricted Travel in Solar Cells
In the past 2 years, organolead halide perovskites have emerged as a promising class of light-harvesting media in experimental solar cells, but the physical basis for their efficiency has been unclear (see the Perspective by
Hodes
). Two studies now show, using a variety of time-resolved absorption and emission spectroscopic techniques, that these materials manifest relatively long diffusion paths for charge carriers energized by light absorption.
Xing
et al.
(p.
344
) independently assessed (negative) electron and (positive) hole diffusion lengths and found them well-matched to one another to the ~100-nanometer optical absorption depth.
Stranks
et al.
(p.
341
) uncovered a 10-fold greater diffusion length in a chloride-doped material, which correlates with the material's particularly efficient overall performance. Both studies highlight effective carrier diffusion as a fruitful parameter for further optimization.
