Preparation of Efficient and Stable Perovskite Solar Cells Based on Amino Acid Derivative Hydrochloride Additives
The rapid development of perovskite solar cells(PSCs)has made them one of the most competitive photo-voltaic devices in the field of new energy.However,there is still great room for improvement in photoelectric conversion efficiency(PCE)and stability.Here,an amino acid derivative hydrochloride was introduced as an additive in perovskite,D-phenylglycine methyl ester hydrochloride(PGMECl).PGMECl contains a benzene ring,an ester group,—NH3+ terminal and Cl-ions.The multiple functional groups worked together to react with uncoordinated Pb2+,passivating defects in perovskite.The perovskite grains became denser,surface roughness decreased,and non-radiative recombination of charge carriers was reduced.By adjusting the energy level arrangement,it is more suitable for charge transfer in inverted perovskite solar cells.The results showed that the champion power conversion efficiency(PCE)of PGMECl modification device is 21.04%,which is much higher than that of control devices(17.79%).The decrease in hysteresis effect also indicates a decrease in ion migration.Under unencapsulated conditions,devices containing PGMECl additives can still maintain a PCE of 70%of the initial efficiency after aging in the dark in air[(40±5)%relative humidity(RH)]for 1000 h,while the efficiency of the basic device decreases to 50%after 500 h of storage.
D-phenylglycine methyl ester hydrochloridePerovskite solar cellPower conversion efficiencyStability