摘要
The deep-level traps induced by charged defects at the grain boundaries(GBs)of polycrystalline organic-inorganic halide perovskite(OIHP)films serve as major recombination centres,which limit the device performance.Herein,we incorporate specially designed poly(3-aminothiophenol)-coated gold(Au@PAT)nanoparticles into the perovskite absorber,in order to examine the influence of plasmonic resonance on carrier dynamics in perovskite solar cells.Local changes in the photophysical properties of the OIHP films reveal that plasmon excitation could fill trap sites at the GB region through photo-brightening,whereas transient absorption spectroscopy and density functional theory calculations correlate this photo-brightening of trap states with plasmon-induced interfacial processes.As a result,the device achieved the best efficiency of 22.0%with robust operational stability.Our work provides unambiguous evidence for plasmon-induced trap occupation in OIHP and reveals that plasmonic nanostructures may be one type of efficient additives to overcome the recombination losses in perovskite solar cells and thin-film solar cells in general.
基金
This work was supported by the National Natural Science Foundation of China(Grants 51863013 and 61874052)
K.Y.thanks the financial support of Excellent Young Foundation of Jiangxi Province(Grant 20192BCB23009)
the Hong Kong Scholars programme(XJ2016048)
P.D.and T.S.thank the financial support of the Grant agency of the Czech Republic(number 20-01673S)
This work was also supported by the Hong Kong Polytechnic University(G-YZ98)
the Research Grants Council of Hong Kong(GRF Grant number PolyU152140/19E and CRF Grant number C5037-18G).
