DOI: 10.3724/SP.J.1249.2017.05509

Journal of Shenzhen University Science and Engineering (深圳大学学报理工版) 2017/34:5 PP.509-515

Double-solutions effect on preparation of perovskite thin films and photovoltaic performance of related solar cells

CH3NH3PbI3 perovskite films and the perovskite solar cells were prepared via reaction of PbI2 films and CH3NH3I (MAI) solutions of different concentrations under high-humidity ambient conditions.It was found that high concentration MAI solution contributes to the formation of the dense films with nano-scale perovskite grains, while low concentration MAI solution results in rough films with micrometer-scale grains and many voids and openings. None of these films could benefit the high-performance perovskite solar cells from the aspects of grain boundaries and coverage area. In order to overcome the disadvantage of the single solution method,modified double solution method was developed. Eight mg/mL low concentration MAI solution was used to react with PbI2 films for 10 s and then high concentration MAI solutions of 15 and 30 mg/mL were used for post-treatment. Consequently, dense CH3NH3PbI3 perovskite films with large-scale grains with little PbI2 residue were obtained. Accordingly, the perovskite solar cells fabricated in ambient conditions by this method exhibit a good photovoltaic performance.

Key words:condensed matter physics,thin-film solar cells,perovskite film,double solution method,microstructures,photovoltaic performance

ReleaseDate:2017-10-20 02:07:31

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