Insights of Unconventionally Long Exposure Time in Atomic Layer Deposition Al₂O₃ to Modify SnO₂ Photoanode of Dye-Sensitized Solar Cells

【摘要】 Porous SnO₂ photoanodes coated by alumina through atomic layer deposition technology are reported.It is found that when the dosing time of precursor is extended over 11 s,the 125%maximum increase of cell efficiency is achieved.It is believed that besides the interfacial charge recombination being efficiently suppressed by this ultra-thin coating,the increased absorption of dyes and elimination of the high density of monoenergetic surface states on SnO₂ might play a positive role in improving the cell efficiency.The reason is that a long exposure time of precursor can guarantee the 100%coverage of alumina on porous SnO₂,which is further explained by a built three-step model.Then we conclude that for a high cell efficiency in porous photoelectrode a long exposure time is indispensable.更多还原

【Abstract】 Porous SnO₂ photoanodes coated by alumina through atomic layer deposition technology are reported.It is found that when the dosing time of precursor is extended over 11 s,the 125%maximum increase of cell efficiency is achieved.It is believed that besides the interfacial charge recombination being efficiently suppressed by this ultra-thin coating,the increased absorption of dyes and elimination of the high density of monoenergetic surface states on SnO₂ might play a positive role in improving the cell efficiency.The reason is that a long exposure time of precursor can guarantee the 100%coverage of alumina on porous SnO₂,which is further explained by a built three-step model.Then we conclude that for a high cell efficiency in porous photoelectrode a long exposure time is indispensable.更多还原