Interface Passivation of Inverted Perovskite Solar Cells by Dye Molecules

The interface between [6,6]-phenyl C61-butyric acid methyl ester (PC61BM) and the electrode has a critical effect on the performance of inverted perovskite solar cells (PSCs). Three organic cationic cyanine dye molecules with different highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) states are designed to passivate the PC61BM and Ag electrode interface to improve PSCs performance. The effects of energy-level alignment and the interfacial charge transfer resistance on the device performance are compared and studied. The dye interface passivation layer significantly reduces charge recombination. Moreover, the ClO4– anions associated with the dye molecules improve the charge extraction and charge transport in the devices. Reduced interface charge recombination and improved charge transport are confirmed by photoluminescence (PL), time-resolved photoluminescence (TRPL), electrochemical impedance spectra (EIS), and charge-only device performance studies. The PSCs with one of the dyes as an interface passivation layer show an optimized power conversion efficiency (PCE) of 19.14% with an open-circuit voltage (Voc) of 1.09 V, a short-circuit current density (Jsc) of 22.87 mA/cm2, and a fill factor (FF) of 76.81%. The devices maintain over 90% of the initial PCE for 120 h of storage under an ambient environment (25 °C and 30 ± 5% relative humidity (RH). The use of small dye molecules as an interface passivation layer to reduce charge recombination in PSCs represents a paradigm for improving the performance and stability of PSCs

Enhanced Perovskite Solar Cell Performance via 2‑Amino-5-iodobenzoic Acid Passivation

The intrinsic stability issues of the perovskite materials threaten the efficiency and stability of the devices, and stability has become the main obstacle to industrial applications. Herein, the efficient and facile passivation strategy by 2-amino-5-iodobenzoic acid (AIBA) is proposed. The impact of AIBA on the properties of the perovskite films and device performance is systemically studied. The results show that the trap states are eliminated without affecting the crystal properties of the perovskite grains, leading to the enhanced performance and stability of the perovskite solar cells (PSCs). A high power conversion efficiency (PCE) of 20.23% and lower hysteresis index (HI) of 1.49‰ are achieved, which represent one of the most excellent PCE and HI values for the inverted PSCs based on MAPbI3/[6,6]-Phenyl-C61-Butyric Acid Methyl Ester (PCBM) planar heterojunction structure. Moreover, the UV stability of the perovskite films and the thermal and moisture stability of the devices are also enhanced by the AIBA passivation. The PCE of the device with AIBA can maintain about 83.41% for 600 h (40 RH %) and 64.06% for 100 h (55–70 RH %) of its initial PCE value without any encapsulation, while the control device can maintain only about 72.91 and 45.59% of its initial PCE. Density functional theory calculations are performed to study the origins of enhanced performance. Interestingly, the results show that the surface states induced by AIBA can facilitate the photoexcited charge transfer dynamics and reduce the electron–hole recombination loss. The passivation method developed in this work provides an efficient way to enhance the stability and performance of inverted PSCs

Universal Surface Passivation of Organic–Inorganic Halide Perovskite Films by Tetraoctylammonium Chloride for High-Performance and Stable Perovskite Solar Cells

The power conversion efficiency (PCE) of perovskite solar cells has been showing rapid improvement in the last decade. However, still, there is an unarguable performance deficit compared with the Schockley–Queisser (SQ) limit. One of the major causes for such performance discrepancy is surface and grain boundary defects. They are a source of nonradiative recombination in the devices that not only causes performance loss but also instability of the solar cells. In this study, we employed a direct postsurface passivation strategy at mild temperatures to modify perovskite layer defects using tetraoctylammonium chloride (TOAC). The passivated perovskite layers have demonstrated extraordinary improvement in photoluminescence and charge carrier lifetimes compared to their control counterparts in both Cs0.05(FAPbI3)0.83(MAPbBr3)0.17 and MAPbI3-type perovskite layers. The investigation on electron-only and hole-only devices after TOAC treatment revealed suppressed electron and hole trap density of states. The electrochemical study demonstrated that TOAC treatment improved the charge recombination resistance of the perovskite layers and reduced the charge accumulation on the surface of perovskite films. As a result, perovskite solar cells prepared by TOAC treatment showed a champion PCE of 21.24% for the Cs0.05(FAPbI3)0.83(MAPbBr3)0.17-based device compared to 19.58% without passivation. Likewise, the PCE of MAPbI3 improved from 18.09 to 19.27% with TOAC treatment. The long-term stability of TOAC-passivated perovskite Cs0.05(FAPbI3)0.83(MAPbBr3)0.17 devices has retained over 97% of its initial performance after 720 h in air

Efficient and Stable Self-Passivation Perovskite Solar Cells Prepared in Ambient Air Based on an Antisolvent-Free Method

Solution processable perovskite solar cells (PSCs) are one of the most promising candidates for commercialization. However, the perovskite film preparation method is limited by the mandatory antisolvent process under an inert gas atmosphere which significantly influenced its mass production. In this study, we developed a perovskite film preparation without the requirement of antisolvent dripping in air. We employed various solvents to prepare perovskite films and studied their influence on perovskite nucleation and morphology for the respective solvents. Among them, the perovskite prepared using dimethylacetamide (DMAc), which has low solubility and high interaction with PbI2, demonstrated a highly crystalline perovskite black phase without antisolvent dripping. Furthermore, we found that the perovskite concentration played an important role in the perovskite film quality, where the high concentration DMAc-based perovskite produced a smooth and dense perovskite film by the antisolvent-free method in air. PSCs fabricated using this technique delivered a champion power conversion efficiency (PCE) of 20.1%. At the same time, the best device prepared by the blade-coated method also got 18% PCE. Moreover, the unencapsulated devices exhibited excellent stability, which retained more than 90% of their initial efficiency after 47 days in air. This work provides a facile and cost-effective method toward a controllable fabrication of high-performance antisolvent-free MAPbI3-based solar cells

Efficient and Stable Self-Passivation Perovskite Solar Cells Prepared in Ambient Air Based on an Antisolvent-Free Method

Solution processable perovskite solar cells (PSCs) are one of the most promising candidates for commercialization. However, the perovskite film preparation method is limited by the mandatory antisolvent process under an inert gas atmosphere which significantly influenced its mass production. In this study, we developed a perovskite film preparation without the requirement of antisolvent dripping in air. We employed various solvents to prepare perovskite films and studied their influence on perovskite nucleation and morphology for the respective solvents. Among them, the perovskite prepared using dimethylacetamide (DMAc), which has low solubility and high interaction with PbI2, demonstrated a highly crystalline perovskite black phase without antisolvent dripping. Furthermore, we found that the perovskite concentration played an important role in the perovskite film quality, where the high concentration DMAc-based perovskite produced a smooth and dense perovskite film by the antisolvent-free method in air. PSCs fabricated using this technique delivered a champion power conversion efficiency (PCE) of 20.1%. At the same time, the best device prepared by the blade-coated method also got 18% PCE. Moreover, the unencapsulated devices exhibited excellent stability, which retained more than 90% of their initial efficiency after 47 days in air. This work provides a facile and cost-effective method toward a controllable fabrication of high-performance antisolvent-free MAPbI3-based solar cells

Efficient and Stable Self-Passivation Perovskite Solar Cells Prepared in Ambient Air Based on an Antisolvent-Free Method

Solution processable perovskite solar cells (PSCs) are one of the most promising candidates for commercialization. However, the perovskite film preparation method is limited by the mandatory antisolvent process under an inert gas atmosphere which significantly influenced its mass production. In this study, we developed a perovskite film preparation without the requirement of antisolvent dripping in air. We employed various solvents to prepare perovskite films and studied their influence on perovskite nucleation and morphology for the respective solvents. Among them, the perovskite prepared using dimethylacetamide (DMAc), which has low solubility and high interaction with PbI2, demonstrated a highly crystalline perovskite black phase without antisolvent dripping. Furthermore, we found that the perovskite concentration played an important role in the perovskite film quality, where the high concentration DMAc-based perovskite produced a smooth and dense perovskite film by the antisolvent-free method in air. PSCs fabricated using this technique delivered a champion power conversion efficiency (PCE) of 20.1%. At the same time, the best device prepared by the blade-coated method also got 18% PCE. Moreover, the unencapsulated devices exhibited excellent stability, which retained more than 90% of their initial efficiency after 47 days in air. This work provides a facile and cost-effective method toward a controllable fabrication of high-performance antisolvent-free MAPbI3-based solar cells

Efficient and Stable Self-Passivation Perovskite Solar Cells Prepared in Ambient Air Based on an Antisolvent-Free Method

Solution processable perovskite solar cells (PSCs) are one of the most promising candidates for commercialization. However, the perovskite film preparation method is limited by the mandatory antisolvent process under an inert gas atmosphere which significantly influenced its mass production. In this study, we developed a perovskite film preparation without the requirement of antisolvent dripping in air. We employed various solvents to prepare perovskite films and studied their influence on perovskite nucleation and morphology for the respective solvents. Among them, the perovskite prepared using dimethylacetamide (DMAc), which has low solubility and high interaction with PbI2, demonstrated a highly crystalline perovskite black phase without antisolvent dripping. Furthermore, we found that the perovskite concentration played an important role in the perovskite film quality, where the high concentration DMAc-based perovskite produced a smooth and dense perovskite film by the antisolvent-free method in air. PSCs fabricated using this technique delivered a champion power conversion efficiency (PCE) of 20.1%. At the same time, the best device prepared by the blade-coated method also got 18% PCE. Moreover, the unencapsulated devices exhibited excellent stability, which retained more than 90% of their initial efficiency after 47 days in air. This work provides a facile and cost-effective method toward a controllable fabrication of high-performance antisolvent-free MAPbI3-based solar cells

Efficient and Stable Self-Passivation Perovskite Solar Cells Prepared in Ambient Air Based on an Antisolvent-Free Method

Solution processable perovskite solar cells (PSCs) are one of the most promising candidates for commercialization. However, the perovskite film preparation method is limited by the mandatory antisolvent process under an inert gas atmosphere which significantly influenced its mass production. In this study, we developed a perovskite film preparation without the requirement of antisolvent dripping in air. We employed various solvents to prepare perovskite films and studied their influence on perovskite nucleation and morphology for the respective solvents. Among them, the perovskite prepared using dimethylacetamide (DMAc), which has low solubility and high interaction with PbI2, demonstrated a highly crystalline perovskite black phase without antisolvent dripping. Furthermore, we found that the perovskite concentration played an important role in the perovskite film quality, where the high concentration DMAc-based perovskite produced a smooth and dense perovskite film by the antisolvent-free method in air. PSCs fabricated using this technique delivered a champion power conversion efficiency (PCE) of 20.1%. At the same time, the best device prepared by the blade-coated method also got 18% PCE. Moreover, the unencapsulated devices exhibited excellent stability, which retained more than 90% of their initial efficiency after 47 days in air. This work provides a facile and cost-effective method toward a controllable fabrication of high-performance antisolvent-free MAPbI3-based solar cells

Efficient and Stable Self-Passivation Perovskite Solar Cells Prepared in Ambient Air Based on an Antisolvent-Free Method

Solution processable perovskite solar cells (PSCs) are one of the most promising candidates for commercialization. However, the perovskite film preparation method is limited by the mandatory antisolvent process under an inert gas atmosphere which significantly influenced its mass production. In this study, we developed a perovskite film preparation without the requirement of antisolvent dripping in air. We employed various solvents to prepare perovskite films and studied their influence on perovskite nucleation and morphology for the respective solvents. Among them, the perovskite prepared using dimethylacetamide (DMAc), which has low solubility and high interaction with PbI2, demonstrated a highly crystalline perovskite black phase without antisolvent dripping. Furthermore, we found that the perovskite concentration played an important role in the perovskite film quality, where the high concentration DMAc-based perovskite produced a smooth and dense perovskite film by the antisolvent-free method in air. PSCs fabricated using this technique delivered a champion power conversion efficiency (PCE) of 20.1%. At the same time, the best device prepared by the blade-coated method also got 18% PCE. Moreover, the unencapsulated devices exhibited excellent stability, which retained more than 90% of their initial efficiency after 47 days in air. This work provides a facile and cost-effective method toward a controllable fabrication of high-performance antisolvent-free MAPbI3-based solar cells