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An exquisite, engineering of two poor hole transporting materials (HTMs, SnO, and PDTON) to form an excellent double‐layered HTL (SnO/PDTON) for inverted tin‐perovskite solar modules (TPSMs) is developed. SnO/PDTON has better photovoltaic performance than the commonly used PEDOT:PSS HTM when large‐area TPSMs are fabricated. Thermally evaporated SnO (that is a simple, available oxide with high hole mobility, good transparency, and adjustable frontier orbitals energy levels) film is used as a main hole transporting layer (HTL). Amphiphilic polymer PDTON (having the amine and ether groups on the side chains) film is used as a Co‐HTL, cross‐linker, passivator, and interface modification agent, as unveiled various physicochemical studies. Double‐layered SnO/PDTON with a flat morphology and good affinity toward perovskite precursor solution creates also a proper surface for depositing large‐area, high‐quality TPsk film. Therefore, TPSM (25.2 cm2 active area on 10 cm × 10 cm ITO substrate) based on double‐layered SnO/PDTON HTL achieving an efficiency over 10% with a negligible current hysteresis is reported for the first time. This study emphasizes not only the exquisite design of combining the specific characteristics of two prosaic HTMs to become a good double‐layered HTL but also gives a direction toward fabricating TPSMs to be applied in all‐perovskite tandem solar module. [ABSTRACT FROM AUTHOR]

Low‐temperature sol‐gel prepared ZnCo2O4 spinel‐based thin films are developed as high‐performance hole transporting layer (HTL) for coating perovskite film (NA‐Psk) from the basic MAPbI3/ACN/CH3NH2 solution in air without using anti‐solvent. Inverted PSC based on 2 mole% (vs Zn) Cu2+ doped ZnCo2O4 (2%Cu@ZnCo2O4) HTL and NA‐Psk absorber exhibit the maximum power conversion efficiency (PCE) of 20.0% with no current hysteresis while the cell based on ZnCo2O4 and PEDOT:PSS HTL (using NA‐Psk absorber) achieves the PCE of 15.79% and 12.3% with a current hysteresis index of 9.8% and 32.4%, respectively. Without encapsulation, PSCs based on 2%Cu@ZnCo2O4, ZnCo2O4, and PEDOT:PSS HTLs maintain 90%, 77%, and 12%, respectively of the original efficiency by standing in ambient atmosphere (temperature: 20–25 °C, RH:30%–40%) for 1800 h. Large area (10 cm × 10 cm substrate) perovskite mini‐module (PSM) with PCE over 15% is also demonstrated by using sol‐gel prepared 2%Cu@ZnCo2O4 HTL. The poor photovoltaic performance of PEDOT:PSS HTL is due to the basic MAPbI3/ACN/CH3NH2 solution will deprotonate the acidic PEDOT:PSS to reduce its conductivity whereas ZnCo2O4 HTL are not affected by basic perovskite precursor solution. [ABSTRACT FROM AUTHOR]

High-quality perovskite film is deposited on a 30 cm × 40 cm LiCoO2-coated ITO/glass via newly developed freely falling anti-solvent extraction (FFASE) method followed by post watervapor annealing in an ambient atmosphere. Perovskite solar modules (PSMs, active area of 25.2 cm2 with mask) based on this high-quality film achieve the highest efficiency of 16.04 and 30.76% under 1 sun (100 mW cm-2) and 945 lux fluorescent light illumination, respectively. The encapsulated PSMs are stable at -20 to 80 °C thermal cycling and keep high efficiency at temperature as low as -20 °C and as high as 80 °C. When the encapsulated PSM is heated at 85 °C and 85% relative humidity under room lighting or heated at 60 °C under AM1.5 (100 mW cm-2) illumination for 1000 h, loses only "8% of its original efficiency. The high stability of PSMs is due to very high quality perovskite absorber being used. The underlying concept of the FFASE method for extracting the solvent from the large-area perovskite precursor film is that the whole precursor film contacts with the fresh anti-solvent during the crystallization stage. [ABSTRACT FROM AUTHOR]

The defects at the interface and grain boundaries of perovskite films downgrade the performance of perovskite solar cells (PSCs) dramatically. Hence, improving perovskite film quality is essential for the achievement of high-performance solar cells. Herein, three new dicyclopentadithienothiophene (DCDTT)-based non-fullerene acceptors (NFAs) IN-DCDTT (1), INCl-DCDTT (2), and INBr-DCDTT (3) are developed as a promising platform for organic–inorganic hybrid perovskite solar cells to achieve simple preparation, high efficiency, and good stability. SEM and XRD data indicate that, with the addition of chlorinated NFA 2 in the active layer preparation, perovskite hybrid films exhibit larger grain sizes and higher crystallinity than pristine perovskite films. As shown by EDS and IR, all the non-fullerene acceptors (compounds 1–3) with functional carbonyl (C＝O) and cyano (C≡N) groups have good interaction with undercoordinated Pb atoms and passivate the trap states in the perovskite films. Time-resolved photoluminescence reveals that the molecule INCl-DCDTT (2) facilitates efficient hole extraction. Consequently, solar cells based on 2−perovskite hybrid films yield an excellent power conversion efficiency of 21.39% with an FF of 0.82, a Jsc of 23.71 mA cm−2, and a Voc of 1.10 V, which represents a significant improvement as compared to a PCE of 17% obtained for the control device. Meanwhile, devices based on IN-DCDTT (1) and INBr-DCDTT (3)−perovskite hybrid films also show enhanced performance with a slightly lower PCE of 19.21% and 20.59%, respectively than cells based on 2−perovskite hybrid films. The cost-effective chlorinated INCl-DCDTT (2) and brominated INBr-DCDTT (3) organic small molecules were successfully used as donor passivation agents to improve the photovoltaic performance of Pb-based PSCs. Furthermore, compound 1–3 derived PSC devices also exhibit excellent long-term stability enhancement. In particular, a device based on INCl-DCDTT (2) treated perovskite retains ∼90% of the initial PCE after 63 days in a glove box as compared to that (55%) of the control device. This simple surface treatment, by the addition of new NFAs, provides a new strategy to simultaneously passivate surface defects and enhance charge transport at the device interface. [ABSTRACT FROM AUTHOR]

The oxide/nitride passivation and the flip‐chip package technology are developed for the perovskite solar cells. The heat resulting from the physical vapor deposition decomposes the active perovskite layer and degrades the efficiency of the perovskite solar cells down by more than 45%. Remarkably, with Si‐nitride passivation processed by plasma‐enhanced vapor deposition, the efficiency of the perovskite solar cell only decays about 9.1%. It is because that the plasma‐enhanced vapor deposition causes much less external energy on the perovskite solar cell. Using the exponential efficiency‐decay curves of the flip‐chip packaged perovskite solar cells, the characteristic time of the reliability‐tested solar cell can be calculated to be 145.8, 390.7, and 4864 h for air‐ambient, glove chamber, and water‐ambient tests, respectively. It is concluded that the concentration of O2(g) in the reliability test ambient is the root cause for the efficiency degradation of the perovskite solar cells. The low mobility of O2(g) under the water‐ambient reliability test results in the low probability of the adsorption of O2(g) on the surface of the flip‐chip package, which is the key factor for the least efficiency degradation of the perovskite solar cells among the three reliability tests. [ABSTRACT FROM AUTHOR]

A series of monochloro‐s‐triazinyl (MCT) and related m‐carboxypyridinium‐s‐triazinyl (nicotinic acid [NTR]) reactive dyes based on the same red chromophore and bearing –NHCN, –OCH3, –N(CH3)SO2CH3, –N‐methylphenyl and –OH "second‐leg" substituents were evaluated in cold pad‐batch dyeing. It was found that both the MCT and NTR dyes containing a cyanoamino second‐leg substituent displayed a superior technical performance to the dyes bearing methoxy, N‐methyl(methylsulphonyl)amino, hydroxyl and N‐methylaniline substituents. The results suggest that these technical benefits of dyeing are derived from the smaller molecule size and electronic effect of the cyanoamino group compared with the other second‐leg substituents commonly used in both MCT and NTR reactive dye synthesis. Indeed, the use of the cyanoamino second leg on the studied red NTR reactive dyes offered a combination of short batch time, high fixation efficiency, good build‐up properties and good wet fastness properties. [ABSTRACT FROM AUTHOR]