[18p-P09-1~54] 12.5 Organic and hybrid solar cells

English Presentation

[18p-P09-17] Effective Defect Passivation at the Grain Boundaries and the Perovskite/ETL Interface for efficient Tin-Lead perovskite solar cells

〇(P)Safalmani Pradhan¹, Suraya Shaban¹, Ajay Kumar Baranwal¹, Gaurav Kapil¹, Qing Shen¹, Shuzi Hayase¹ (1.UEC-Tokyo)

Keywords:

perovskite solar cells,Tin-Lead perovskite,Surface passivation

The overall power conversion efficiency (PCE) of single junction organic–inorganic metal-halide perovskite solar cells (PSCs) have increased rapidly from 3.8% to 26.1% in the last decade. Although the single-junction lead (Pb)-based PSCs have achieved 26.1% efficiency, the mixed tin-lead (Sn-Pb) perovskites provide room for band gap tuningthus allowing even better performance. However, non-radiative recombination losses due to high defect concentrations at the grain boundaries and at the perovskite/electron transporting layer (ETL) interface leads to hampered performance. Phenylethylammonium chloride (PEACl) has been utilized as an additive in this work in order to passivate the grain boundaries and thereby reduce the defect concentrations. In order to passivate the perovskite/ETL interface, organic small molecules such as ethylenediamine (EDA), piperazine (PZ) and pipperazinium dihydroiodide (PZDI) has been utilized. The findings of this study suggests that the effective passivation of the perovskite grain boundaries and the defects in the perovskite/ETL interface is crucial for improving the photovoltaic performance. The effective passivation of the perovskite grain boundaries with PEACl along with the effective passivation of perovskite/ETL interface with EDA led to a good photovoltaic performance with a short-circuit current density (J_sc) of 26.11 mA/cm², open-circuit voltage (V_oc) of 0.86 V, Fill Factor (FF) of 0.80 leading to an overall PCE of 18.01%. It should be noted that alternative surface passivants, viz., PZ and PZDI also exhibited good photovoltaic performance.