Ultra-high open-circuit voltage of tin perovskite solar cells via an electron transporting layer design

Abstract

Tin perovskite is rising as a promising candidate to address the toxicity and theoretical efficiency limitation of lead perovskite. However, the voltage and efficiency of tin perovskite solar cells are much lower than lead counterparts. Herein, indene-C 60 bisadduct with higher energy level is utilized as an electron transporting material for tin perovskite solar cells. It suppresses carrier concentration increase caused by remote doping, which significantly reduces interface carriers recombination. Moreover, indene-C 60 bisadduct increases the maximum attainable photovoltage of the device. As a result, the use of indene-C 60 bisadduct brings unprecedentedly high voltage of 0.94 V, which is over 50% higher than that of 0.6 V for device based on [6,6]-phenyl-C61-butyric acid methyl ester. The device shows a record power conversion efficiency of 12.4% reproduced in an accredited independent photovoltaic testing lab.

Self‐Repairing Tin‐Based Perovskite Solar Cells with a Breakthrough Efficiency Over 11%

“…[31] Large ammonium cations, such as ethylenediammonium (EDA 2+ ) and phenylethylammonium (PEA + ) have been introduced, [32][33][34] and have shown great potential in Sn-based perovskite. [35,36] Herein, we introduce an additive with large reductive cation, phenylhydrazine hydrochloride (PHCl), into FASnI 3 films in order to passivate trap states and improve stability. It is proven by X-ray diffraction (XRD) and grazing incidence wide-angle X-ray scattering (GIWAXS) that phenylhydrazine ions (PH + ) are successfully incorporated into the crystal lattice without forming a 2D structure.…”

Efficient and Stable Tin Perovskite Solar Cells Enabled by Graded Heterostructure of Light‐Absorbing Layer

“…The large energy‐level offset between tin perovskite and the commonly used electron transport materials suppresses the quasi‐Fermi level splitting and provides additional channels that accelerate the trap‐assisted recombination process. [ 27 ]…”

Perovskite‐Based Tandem Solar Cells: Get the Most Out of the Sun

“…Generally, intrinsically Sn-based perovskites show narrow bandgap down to 1.2-1.4 eV, approaching the optimum bandgap of 1.1 eV for the bottom cell in tandem devices. However, these perovskites exhibit poor stabilities, and the highest efficiency of intrinsically Sn-based PSCs is merely 12.4%, [56] due to high defect density and low carrier lifetime. [57,58] More importantly, poor reproducibility and serious instability problems keep the intrinsic Sn-based perovskite from being used as useful solar cell materials.…”

“…[64,65] So far, the efficiency of state-of-the-art single-junction Pb-Sn perovskite (FA 0.7 MA 0.3 Pb 0.5 Sn 0.5 I 3 , 1.22 eV) solar cells has reached 21.1%, [66] which is much higher than that of all-Sn based PSCs (12.4%), but still lower than that of all Pb based counterparts. [56,67] Furthermore, with the narrow-bandgap perovskite of (FASnI 3 ) 0.6 (MAPbI 3 ) 0.4 (1.25 eV) as the absorber in bottom cell, the resultant 4T APTSC has achieved a record efficiency of 25.0%, [68] which approaches the 25.2% world-record efficiency of single-junction PSCs. [4] More encouragingly, the achievable efficiency of the APTSC is estimated to feasibly approach 32% based on the combination of state-of-the-art wide-bandgap and narrow-bandgap perovskites as the top subcell and the bottom subcell, respectively.…”