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Nowadays, amine containing electrode interface material destroy the non‐fullerene acceptor becomes a hard nut to crack for organic solar cells. Developing water‐soluble interface material which is no chemical reaction with non‐fullerene acceptor is an important research theme. Here, we report two bi‐triangular pyramidal electronic configuration organic‐phosphonium bromides as non‐amine cathode interfacial layer for fabricating high‐efficiency stable organic solar cells. The power conversion efficiency (PCE) of inverted device structure with PBDB‐T/ITIC as active layer is up to 11.58 % which is great larger than control device PCE (9.35 %). Same device structure with PM6/Y6 as active layer, the PCE is up to 15.26 % and also is dramatically higher than the referred device PCE 14.36 %. Meanwhile, the devices show greatly improved stability by organic‐phosphonium bromide interlayer. [ABSTRACT FROM AUTHOR]

Methylammonium chloride (MACl) additive is almost irreplaceable in high‐performance formamidine perovskite photovoltaics. Nevertheless, Some of the problems that can arise from adding MACl are rarely mentioned. Herein, it is proposed for the first time that the addition of MACl would cause the non‐stoichiometric ratio in the perovskite film, resulting in the halogen vacancy. It is demonstrated that the non‐synchronous volatilization of methylamine cations and chloride ions leads to the formation of halogen vacancy defects. To solve this problem, the NH4HCOO is introduced into the perovskite precursor solution to passivate the halogen vacancy. The HCOO− ions have a strong force with lead ions and can fill the halogen vacancy defects. Consequently, the champion devices' power conversion efficiency (PCE) can be improved from 21.23% to 23.72% with negligible hysteresis. And the unencapsulated device can still retain >90% of the initial PCE even operating in N2 atmosphere for over 1200 h. This work illustrates another halogen defect source in the MACl‐assisted formamidine perovskite photovoltaics and provides a new route to obtain high‐performance perovskite solar cells. [ABSTRACT FROM AUTHOR]

The remarkable optoelectronic properties of organometal halide perovskite solar cells have captivated significant attention in the energy sector. Nevertheless, the instability of 3D perovskites, despite their extensive study and attainment of high-power conversion efficiency, remains a substantial obstacle in advancing PSCs for practical applications and eventual commercialization. To tackle this issue, researchers have devised mixed-dimensional perovskite structures combining 1D and 3D components. This innovative approach entails incorporating stable 1D perovskites into 3D perovskite matrices, yielding a significant improvement in long-term stability against various challenges, including moisture, continuous illumination, and thermal stress. Notably, the incorporation of 1D perovskite yields a multitude of advantages. Firstly, it efficiently passivates defects, thereby improving the overall device quality. Secondly, it retards ion migration, a pivotal factor in degradation, thus further bolstering stability. Lastly, the inclusion of 1D perovskite facilitates charge transport, ultimately resulting in an elevated device efficiency. In this succinct review, we thoroughly encapsulate the recent progress in PSCs utilizing 1D/3D mixed-dimensional architectures. These advancements encompass both stacked bilayer configurations of 1D/3D structures and mixed monolayer structures of 1D/3D. Additionally, we tackle critical challenges that must be surmounted and offer insights into the prospects for further advancements in this domain. [ABSTRACT FROM AUTHOR]

Although Metal oxide ZnO is widely used as electron transport layers in all‐inorganic PSCs due to high electron mobility, high transmittance, and simple preparation processing, the surface defects of ZnO suppress the quality of perovskite film and inhibit the solar cells' performance. In this work, [6,6]‐Phenyl C61 butyric acid (PCBA) modified zinc oxide nanorods (ZnO NRs) is employed as electron transport layer in perovskite solar cells. The resulting perovskite film coated on the zinc oxide nanorods has better crystallinity and uniformity, facilitating charge carrier transportation, reducing recombination losses, and ultimately improving the cells' performance. The perovskite solar cell with the device configuration of ITO/ZnO nanorods/PCBA/CsPbIBr2/Spiro‐OMeTAD/Au delivers a high short circuit current density of 11.83 mA cm−2 and power conversion efficiency of 12.05 %. [ABSTRACT FROM AUTHOR]

Flexible perovskite solar cells (FPSCs) represent a promising technology in the development of next‐generation photovoltaic and optoelectronic devices. SnO2 electron transport layers (ETL) typically undergo significant cracking during the bending process of FPSCs, which can significantly compromise their charge transport properties. Herein, the semi‐planar non‐fullerene acceptor molecule Y6 (BT‐core‐based fused‐unit dithienothiophen [3,2‐b]‐pyrrolobenzothiadiazole derivative) is introduced as the buffer layer for SnO2‐based FPSCs. It is found that the Y6 buffer layer can enhance the ability of charge extraction and bending stability for SnO2 ETL. Moreover, the internal stress of perovskite films is also reduced. As a result, SnO2/Y6‐based FPSCs achieved a power conversion efficiency (PCE) of 20.09% and retained over 80% of their initial efficiency after 1000 bending cycles at a curvature radius of 8 mm, while SnO2‐based devices only retain 60% of their initial PCE (18.60%) upon the same bending cycles. In addition, the interfacial charge extraction is also effectively improved in conjunction with reduced defect density upon incorporation of Y6 on the SnO2 ETL, as revealed by femtosecond transient absorption (Fs‐TA) measurements. [ABSTRACT FROM AUTHOR]

The composite high‐performance electrode is very important for excellent photoelectric devices. Interfacial modification is the dominating method to optimize electrode properties. Two easily synthesized perylene monoimide (PMI)‐derived organic phosphonium bromide salts are found interestingly valuable when they are applied as cathode interlayers (CILs) in bulk heterojunction (BHJ) organic solar cells (OSCs). Using the PBDB‐T:ITIC blend as the BHJ active layer in the inverted device structure, the power conversion efficiency (PCE) is greatly improved from 9.49% of the referenced device, which is without phosphonium CIL, to a PCE of 10.42% with PMI‐triphenyl‐phosphonium bromide (PMI‐TPP) and a PCE of 9.87% with PMI‐trimethoxylphenylphosphonium bromide (PMI‐TMOPP) as the CIL. Moreover, the two organic phosphonium bromide salts are also investigated by the traditional device structure, the PCE is 4.21% for the bare aluminum cathode referenced device, in contrast with a moderate increased PCE of 5.18% with PMI‐TPP CIL or a PCE of 5.05% with PMI‐TMOPP CIL. Therefore, the organic phosphonium bromide salt PMI‐TPP is a promising candidate of CIL material in OSCs. [ABSTRACT FROM AUTHOR]

Chiral quasi‐2D perovskite single crystals (SCs) were investigated for their circular polarized light (CPL) detecting capability. Quasi‐2D chiral perovskites, [(R)‐β‐MPA]2MAPb2I7 ((R)‐β‐MPA=(R)‐(+)‐β‐methylphenethylamine, MA=methylammonium), have intrinsic chirality and the capability to distinguish different polarization states of CPL photons. Corresponding quasi‐2D SCs CPL photodetector exhibit excellent detection performance. In particular, our device responsivity is almost one order of magnitude higher than the reported 2D perovskite CPL detectors to date. The crystallization dynamics of the film were modulated to facilitate its carrier transport. Parallel oriented perovskite films with a homogeneous energy landscape is crucial to maximize the carrier collection efficiency. The photodetector also exhibits superior mechanical flexibility and durability, representing a promising candidate for sensitive and robust CPL photodetectors. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) employing organic-inorganic halide perovskite as active layers have attracted the interesting of many scientists since 2009. The power conversion efficiency (PCE) have pushed certified 25.2% in 2019 from initial 3.81% in 2009, which is much faster than that of any type of solar cell. In the process of optimization, many innovative approaches to improve the morphology of perovskite films were developed, aiming at elevate the power conversion efficiency of perovskite solar cells (PSCs) as well as long-term stability. In the context of PSCs research, the perovskite precursor solutions modified with different additives have been extensively studied, with remarkable progress in improving the whole performance. In this comprehensive review, we focus on the forces induced by additives between the cations and anions of perovskite precursor, such as hydrogen bonds, coordination or some by-product (e.g., mesophase), which will lead to form intermediate adduct phases and then can be converted into high quality films. A compact uniform perovskite films can not only upgrade the power conversion efficiency (PCE) of devices but also improve the stability of PSCs under ambient conditions. Therefore, strategies for the implementation of additives engineering in perovskites precursor solution will be critical for the future development of PSCs. How to manipulate the weak forces in the fabrication of perovskite film could help to further develop high-efficiency solar cells with long-term stability and enable the potential of future practical applications. [ABSTRACT FROM AUTHOR]

Long alkyl‐chain capped ligands are prerequisites for preserving high photoluminescence quantum yield (PLQY) in perovskite nanocrystals (NCs). Unfortunately, the insulating feature of surface ligands potentially hinders carrier transport in light‐emitting diode (LED) devices, which will degenerate the LED performance. To overcome this shortcoming, we introduce a conjugated molecule, 3‐phenyl‐2‐propen‐1‐amine (PPA), into CsPbBr3 NCs through a two‐step surface ligand engineering process. Owing to excellent electrical conductivity of PPA, PPA‐capped CsPbBr3 NCs LEDs exhibit a maximum current efficiency of 23.53 cd A−1, and a maximum luminance of 26,475 cd m−2 at the wavelength of 517 nm. This work offers a new strategy to improve the quality of CsPbBr3 NCs and LEDs by introducing conjugation molecular ligands into the all‐inorganic perovskite nanocrystals. Efficient green light‐emitting diodes were fabricated by using CsPbBr3 nanocrystals with excellent carrier transportation properties, owing to the introduction of conjugated alkyl‐amine through two‐step surface ligand engineering. LEDs exhibit a high luminance of 26,475 cd m−2, a high CE of 23.53 cd A−1 by incorporation conjugation molecular ligand into the all‐inorganic perovskite nanocrystals. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Methyleugenol is a common phenylpropanoid compound found in many plants and has been widely used as a flavoring agent in people's daily life. In this study, a stable isotope dilution assay‐coupled gas chromatography/triple quadrupole mass spectrometry (SIDA‐GC/MS/MS) method was developed for the quantitative determination of methyleugenol in food samples. Methyleugenol‐D3 was synthesized and used as an isotope internal standard for the determination of methyleugenol. The QuEChERS (quick, easy, cheap, effective, rugged and safe) method was applied to the clean‐up of food sample extracts. Confirmation and quantification were carried out by GC/MS/MS. RESULTS: The analytical performance of the method was validated. The determination range of methyleugenol was linear from 4 to 500 µg L−1. Method detection limits for solid food samples, semi‐solid food samples and liquid beverages were 50, 50 and 1 µg kg−1 respectively. Satisfactory recoveries in the range 94.29–100.27% were obtained. Intra‐ and inter‐day precision was also validated and the values were all lower than 9%. The method was successfully applied to quantify methyleugenol in different kinds of food samples. CONCLUSION: This article describes a new method for the accurate quantification of methyleugenol in food samples based on a stable isotope labeling‐assisted GC/MS/MS method. Methyleugenol‐D3 was synthesized and used as an isotope internal standard for the determination of methyleugenol. Excellent results were generated with the method, and the detection sensitivity and accuracy of the method were good. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The method of preparing perovskite films in ambient air is of great importance to commercializing high-performance planar perovskite solar cells (PSCs). Herein, an efficient and stable inverted planar PSC has been prepared via a simple solution method in ambient air. A suitable vanadium oxide (V2Ox) aqueous solution is mixed with a CH3NH3PbI3−xClx precursor solution, resulting in an improvement in the CH3NH3PbI3−xClx film. Perovskite films with large crystal sizes could be obtained using V2Ox additives. The improvement in the performance of perovskite films is conducive to the separation and transmission of charge carriers. For PSCs, the highest power conversion efficiency (PCE) of 16.14% was obtained by controlling the proportion of V2Ox additives in ambient air. It is via a physical mechanism that V2Ox particles are dispersed in the perovskite crystal boundary, and the heterogeneous structure between CH3NH3PbI3−xClx and V2Ox is formed. In addition, the slow migration of iodide ions and stability of the perovskite films are also achieved. What merits more attention is that the PSCs with CH3NH3PbIxCl3−x:V2Ox (2.5 wt%) still maintain a high PCE after being stored for 1000 h, more than 70% of the initial one. [ABSTRACT FROM AUTHOR]

Low-temperature β phase BiNbO4 powders (denoted as Low-β) were prepared by a citrate method using home-made water-soluble niobium precursors. The stability of Low-β was systematically investigated from the aspects including calcination temperature, incubation time, and stress existing in pellets. Pure Low-β can be obtained between 700 and 750 °C and the crystal evolution of Low-β has not completed yet, compared with high-temperature β phase. Low-β is kinetically stable and no phase transition occurs when increasing the incubation time below 750 °C. Above 750 °C, both the calcination temperature and incubation time can induce the abnormal phase transition from Low-β to α phase; also, stress existing in pellets can effectively activate the phase transition of Low-β. We can conclude that the Low- β is thermodynamically unstable, while in kinetics, Low-β is stable. The dielectric properties of BiNbO4 ceramics were investigated to analyze the influence of phase of BiNbO4 powders precursors, especially the effect of phase transition of Low-β. It's found that BiNbO4 powders firstly calcined at 700 °C is the best precursor to prepare dense ceramics with uniform grain size and the dielectric permittivity and dielectric loss of BiNbO4 ceramics prepared at 1000 °C is 56.6 and 0.001 at 10 kHz, respectively. [ABSTRACT FROM AUTHOR]

A series of conjugated polymers with carbazole monomer/dimer/trimer as the donor unit or benzothiadiazole monomer/trimer as the acceptor unit were synthesized and used as donor materials for polymer solar cells (PSCs). The influence of polymer structure on the optical properties and performance of PSCs was investigated in detail. P1 showed a power conversion efficiency (PCE) of 5.8%. The incorporation of longer donor or acceptor unit leads to a blue shift of absorption spectrum and the polymers became more amorphous due to the large torsion angels in the polymer backbone. After increasing the length of donor or acceptor, the PCE decreased dramatically to 0.43% for P2, 0.23% for P3, and 1.23% for P4. Our results have offered a useful insight to structure–property relationship for high performance polymer solar cells. [ABSTRACT FROM AUTHOR]