Abstract
A general and straightforward way of preparing few‐nanometer‐sized well‐separated MAPbIxBr3−x (MA=methylammonium) perovskite photosensitizers on the surface of an approximately 1 μm thick mesoporous TiO2 photoanode was suggested through a two‐step sequential deposition of low‐concentrated lead halides (0.10–0.30 m PbI2 or PbBr2) and methylammonium iodide/bromide (MAI/MABr). When those nanoscale MAPbIxBr3−x perovskites were incorporated as a photosensitizer in typical solid‐state dye‐sensitized solar cells (ss‐DSSCs), it could be verified clearly by the capacitance analysis that nano‐particulate MAPbI3 perovskites play the same role as that of a typical dye sensitizer (MK‐2 molecule) although their size, composition, and structure are different.
Highlights
A general and straightforward way of preparing few-nanometer-sized well-separated MAPbIxBr3Àx (MA = methylammonium) perovskite photosensitizers on the surface of an approximately 1 mm thick mesoporous TiO2 photoanode was suggested through a two-step sequential deposition of low-concentrated lead halides (0.10–0.30 m PbI2 or PbBr2) and methylammonium iodide/bromide (MAI/MABr)
The most successful example of a sensitized solar cell came from a seminal report in 1991, in which molecular dyes anchored onto the surface of mesoscopic TiO2 film as a photosensitizer produced significant current by injecting charges into each electron- and hole-transporting material after absorbing incident light.[1,8]
Molecular dye- or inorganic QD-sensitized solidstate solar cells based on mesoporous metal-oxide films have experienced a very slow rise in overall power conversion efficiencies (PCEs) their importance was clearly recognized in terms of using stable solid hole-conductors relative to volatile liquid electrolytes.[9,10,11b,14] PCEs of typical ss-DSSCs with Spiro-OMeTAD as the best hole-transporting material (HTM) have steady risen up to approximately 7.5 % over 1.0– 2.0 mm thick TiO2 film during the last two decades since the first report of 1.8 %.[9,15]
Summary
We show a simple but effective route for preparing nanoscale MAPbIxBr3Àx (MA = methylammonium) perovskite photosensitizers on relatively thin mesoporous TiO2 films by using a twostep deposition of low-concentrated precursors. This finding indicates clearly that nano-perovskites are working as a photosensitizer based on the same principle as the typical molecular sensitizers in DSSCs. In the few very early results of perovskite solar cell research that were reported as MAPbI3-sensitized type cells,[12] the amount of precursor used was almost the same as that for preparing current bulk perovskite films, usually with a value of approximately 1.0 m.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
