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The photovoltaic performance of inverted perovskite solar cells (PSCs) relies on effectively managing the interface between the hole extraction layer and the light‐absorbing perovskite layer. In this study, we have synthesised (4‐(3,6‐bis(methylthio)‐9H‐carbazol‐9‐yl)butyl)phosphonic acid (MeS‐4PACz), which forms a self‐assembled monolayer (SAM) on the fluorine‐doped tin oxide (FTO) electrode. The molecule‘s methylthio substituents generate a favourable interfacial dipole moment and interact with the perovskite layer. This interaction results in well‐aligned energy levels among the FTO/SAM/perovskite layers, promoting efficient hole extraction and significantly reducing carrier recombination losses. Additionally, the methylthio groups passivate iodide vacancies and interact with Pb2+ ions of the perovskite, reducing defect‐induced trap states and enhancing the crystalline growth of the perovskite layer. Consequently, inverted PSCs incorporating MeS‐4PACz achieve a power conversion efficiency of 25.13 %, along with outstanding photostability. [ABSTRACT FROM AUTHOR]

We have deeply studied vaporized anti-solvents effects on the perovskite solar cell performance. Various non polar anti-solvents were tested to achieve the high quality perovskite film. Depending on the boiling point of the anti-solvent, the surface morphology is dramatically changed. In case of high boiling point anti-solvent, 1,2-dichlorobenzene (180.5 °C) remains on the perovskite surface even after thermal annealing at 100 °C for 10 min. However, the low boiling point chloroform (61.2 °C) anti-solvent makes smooth surface morphology of the perovskite film which leads the high performance of perovskite solar cells. This report introduces the vaporization of the anti-solvent affect the surface morphology that needs careful optimization for high performance perovskite solar cells. [ABSTRACT FROM AUTHOR]

Quasi‐2D perovskite materials have promise to unlock the full potential of blue perovskite light‐emitting diodes (PeLEDs). However, the efficiency of blue emissive PeLEDs still lags behind the green‐ and red‐emitting counterparts. Here, a multifunctional passivating molecule of (2‐(3,6‐dichloro‐9H‐carbazol‐9‐yl)ethyl)phosphonic acid (36ClCzEPA) that can form a self‐assembled monolayer (SAM) on the indium tin oxide (ITO) electrode is reported. The 36ClCzEPA SAM facilitates hole injection by increasing the work function of ITO through the strong interfacial dipole layer formation at the interface between the perovskite emitter and the ITO electrode. Moreover, it allows a pure‐blue emission and reduces the exciton quenching of luminescence in the perovskite emitter considerably because of its neutral nature, compared to the commonly used acidic PEDOT:PSS. Furthermore, chlorine atoms in the 36ClCzEPA promote well‐ordered crystalline 2D perovskite phases and decrease interfacial trap‐assisted deactivation channels by interfacial passivation. These beneficial characteristics of the 36ClCzEPA SAM yield the excellent luminescence property of PeLEDs with a maximum luminance of 1253 cd m−2 and a peak external quantum efficiency of 4.80% at 473 nm. This work demonstrates that a well‐designed molecule forming an interfacial SAM can be an important component for enhancing the luminescence property of pure‐blue PeLEDs. [ABSTRACT FROM AUTHOR]

Abstract The high quality perovskite film construction is the most crucial factor for the high performance perovskite solar cells. Solvent vaopr annelaing (SVA) is one of the best method to achieve the high quality perovkite film. We have fully compared the various high boiling point aprotic solvents N , N -dimethylformamide (DMF), Dimethyl sulfoxide (DMSO) and 1-Methyl-2-pyrrolidone (NMP) for SVA effect for perovskite solar cells. By optimizing temperature and time of SVA, vertically growthed high quality perovskite film via intermediate phase of PbI 2 -NMP structure was achieved which induces high performance of device. PbI 2 -NMP intermediate phase of perovskite film can be attributed to pinhole-free, longer carrier lifetime, and oxygen state free. The optimized device with NMP SVA treatment achieved 15.71% of PCE compared to without SVA treatment 7.85% of PCE. Graphical abstract Image 1 Highlights • Solvent vapor annealing method is one of the best method to achieve good film quality. • Intermediate state with aprotic solvent can induce the high quality perovskite film. • PbI 2 -NMP complex of intermediate state leads to pinhole-free, longer carrier lifetime, and oxygen state free. [ABSTRACT FROM AUTHOR]

Abstract: The development of solution‐processed field effect transistors (FETs) based on organic and hybrid materials over the past two decades has demonstrated the incredible potential in these technologies. However, solution processed FETs generally require impracticably high voltages to switch on and off, which precludes their application in low‐power devices and prevent their integration with standard logic circuitry. Here, a universal and environmentally benign solution‐processing method for the preparation of Ta2O5, HfO2 and ZrO2 amorphous dielectric thin films is demonstrated. High mobility CdS FETs are fabricated on such high‐κ dielectric substrates entirely via solution‐processing. The highest mobility, 2.97 cm2 V−1 s−1 is achieved in the device with Ta2O5 dielectric with a low threshold voltage of 1.00 V, which is higher than the mobility of the reference CdS FET with SiO2 dielectric with an order of magnitude decrease in threshold voltage as well. Because these FETs can be operated at less than 5 V, they may potentially be integrated with existing logic and display circuitry without significant signal amplification. This report demonstrates high‐mobility FETs using solution‐processed Ta2O5 dielectrics with drastically reduced power consumption; ≈95% reduction compared to that of the device with a conventional SiO2 gate dielectric. [ABSTRACT FROM AUTHOR]

Keywords: hole injection layers; interfacial passivation; perovskite light-emitting diodes; quasi-2D perovskites; self-assembled monolayers EN hole injection layers interfacial passivation perovskite light-emitting diodes quasi-2D perovskites self-assembled monolayers 1 1 1 10/20/22 20221015 NES 221015 Highly luminescent pure-blue perovskite light-emitting diodes (PeLEDs) are realized with (2-(3,6-dichloro-9 I H i -carbazol-9-yl)ethyl)phosphonic acid (36ClCzEPA) as multifunctional hole-injection layer. Hole injection layers, interfacial passivation, quasi-2D perovskites, self-assembled monolayers, perovskite light-emitting diodes With the synergetic effects of reduced hole injection barrier by strong interfacial dipole moment and interfacial passivation through the Pb-Cl electronic coupling, the PeLEDs reach a maximum external quantum efficiency of 4.80% at electroluminescence emission of 470 nm. [Extracted from the article]