Improvement of interfacial contact for efficient PCBM/MAPbI₃ planar heterojunction solar cells with a binary antisolvent mixture treatment

Abstract

Atomic-force microscopic images, x-ray diffraction patterns, Urbach energies and photoluminescence quenching experiments show that the interfacial contact quality between the hydrophobic [6,6]-phenyl-C61-buttric acid methyl ester (PCBM) thin film and hydrophilic CH3NH3PbI3 (MAPbI3) thin film can be effectively improved by using a binary antisolvent mixture (toluene:dichloromethane or chlorobenzene:dichloromethane) in the anti-solvent mixture-mediated nucleation process, which increases the averaged power conversion efficiency of the resultant PEDOT:PSS (P3CT-Na) thin film based MAPbI3 solar cells from 13.18% (18.52%) to 13.80% (19.55%). Beside, the use of 10% dichloromethane (DCM) in the binary antisolvent mixture results in a nano-textured MAPbI3 thin film with multicrystalline micrometer-sized grains and thereby increasing the short-circuit current density and fill factor (FF) of the resultant solar cells. It is noted that a remarkable FF of 80.33% is achieved, which can be used to explain the stable photovoltaic performance without additional encapsulations.

Stable and efficient soft perovskite crystalline film based solar cells prepared with a facile encapsulation method

“…S5 † presents the atomic force microscopy (AFM) images of the MAPbI 3 /P3CT-Na/ITO/glass and BCP:PCBM/ MAPbI 3 /P3CT-Na/ITO/glass samples. The surface roughness (R q ) of the samples largely decreases from 10.31 nm to 1.93 nm, which can be used to explain the high contact quality at the BCP:PCBM/MAPbI 3 interface [37][38][39] and thereby resulting in a V OC hysteresis-free characteristic in the J-V curves (see Fig. 3(a)).…”

Enhancing Photovoltaic Performance through Optimized Antisolvent Strategy for Low-Bandgap Pb–Sn Perovskites

“…The substantial enhancement in V OC is likely due to reduced recombination and improved charge extraction, resulting from increased crystallinity and larger grain size with fewer GBs in the EA25-treated perovskite film. 76 Moreover, the smooth surface of the EA25-treated perovskite film facilitates excellent contact with the PCBM layer, promoting efficient charge transport at the interface and contributing to the J SC improvement. The heightened J SC can also be attributed to the narrowed bandgap of the EA25-treated perovskite film, enabling more effective absorption to the solar spectrum.…”

“…The appropriate mixture of EA and CB significantly improved the PV performance, particularly in terms of both the V OC and J SC . The substantial enhancement in V OC is likely due to reduced recombination and improved charge extraction, resulting from increased crystallinity and larger grain size with fewer GBs in the EA25-treated perovskite film . Moreover, the smooth surface of the EA25-treated perovskite film facilitates excellent contact with the PCBM layer, promoting efficient charge transport at the interface and contributing to the J SC improvement.…”

Understanding the PEDOT:PSS, PTAA and P3CT-X Hole-Transport-Layer-Based Inverted Perovskite Solar Cells

“…In the inverted perovskite solar cell, the p-type polymers and p-type metal oxides are widely fabricated on top of the ITO/glass substrates with a post-thermal annealing process at about 100 °C. The high-quality perovskite crystalline thin films can be fabricated by using the two-step spin coating method with an interdiffusion process [ 71 , 72 , 73 ], the one-step spin coating method with a washing-enhanced nucleation (WEN) process [ 74 , 75 , 76 ] and the vacuum thermal co-evaporation technique [ 77 , 78 , 79 ]. The organometal trihalide perovskite can be CH 3 NH 3 PbI 3 (MAPbI 3 ), CH(NH 2 ) 2 PbI 3 (FAPbI 3 ) and Cs x (MA y FA 1−y ) 1−x Pb(I z Br 1−z ) 3 , mainly due to the low absorption bandgap [ 80 , 81 , 82 ], large absorption coefficient [ 83 , 84 , 85 ], small exciton binding energy [ 86 , 87 , 88 ], long exciton (carrier) lifetime [ 89 , 90 , 91 ] and high carrier mobility [ 92 , 93 , 94 ].…”