Enhanced p-i-n type perovskite solar cells by doping AuAg@AuAg core-shell alloy nanocrystals into PEDOT:PSS layer

Metal nanocrystals have shown great potential in the application of solar cell devices, which is ascribed to their enhancement in light-harvesting, due to the plasmonic effects. Herein, we applied AuAg@AuAg (AuAg) core-shell alloy nanocrystals (ANCs) into PEDOT:PSS layer of the p-i-n perovskite solar cells (pero-SCs) as dopant for the first time. The devices based on AuAg ANCs doped PEDOT: PSS reached a champion power conversion efficiency of 16.76%, showing a 28% increase compared with that of the devices based on non-doped PEDOT: PSS (13.14%). Further device characterizations, including incident photon-to-current efficiency, UV-vis absorption spectra, photoluminescence and alternating current impedance spectroscopy, suggested that the significant increase of device performance could mainly attribute to better light harvesting by the scattering effect of AuAg ANCs and better charge transport of the modified PEDOT: PSS layer. This study provides a new doping material in PEDOT: PSS to enhance the light harvesting, which leads to a significant improvement on the performance of pero-SCs.