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Organic solar cells are regarded as a promising strategy for green-energy utilization. Photoactive materials and device technologies have been continually explored. Recently, in the Journal of the American Chemical Society, Xue et al. reported a C-shaped A-D-A NFA, achieving remarkable efficiency (18.32%) with a high Voc(0.92 V).

Recently, deep learning-based fault diagnosis methods have shown promising outcomes in detecting faults within rotating components, relying on substantial labeled training data. However, the scarcity of labeled data is a prevalent challenge in practical engineering and results in unsatisfactory diagnostic results. To address this issue, a semi-supervised fault diagnosis method named dual-stream attention cyclic auto-encoder (DA-CAE) is proposed in this article. First, a CAE is designed to capture and utilize high-dimensional feature information through a cyclic structure. Subsequently, a DA module is incorporated to effectively extract crucial features from a global perspective, thereby enhancing the feature extraction capabilities of the CAE. Finally, a classifier sharing the pretrained CAE is developed and a two-stage training methodology is employed to facilitate fault recognition confronting limited labeled data. The feasibility of the proposed method is validated through experimental data from two rotating components. The results demonstrate that DA-CAE can significantly improve the performance of the auto-encoder (AE) with various label rates and has better superiority compared to the comparison methods, particularly in low-label rate scenarios.

Nanophotonic materials offer spectral and directional control over thermal emission, but in high-temperature oxidizing environments, their stability remains low. This limits their applications in technologies such as solid-state energy conversion and thermal barrier coatings. Here we show an epitaxial heterostructure of perovskite BaZr0.5Hf0.5O3(BZHO) and rocksalt MgO that is stable up to 1,100 °C in air. The heterostructure exhibits coherent atomic registry and clearly separated refractive-index-mismatched layers after prolonged exposure to this extreme environment. The immiscibility of the two materials is corroborated by the high formation energy of substitutional defects from density functional theory calculations. The epitaxy of immiscible refractory oxides is, therefore, an effective method to avoid prevalent thermal instabilities in nanophotonic materials, such as grain-growth degradation, interlayer mixing and oxidation. As a functional example, a BZHO/MgO photonic crystal is implemented as a filter to suppress long-wavelength thermal emission from the leading bulk selective emitter and effectively raise its cutoff energy by 20%, which can produce a corresponding gain in the efficiency of mobile thermophotovoltaic systems. Beyond BZHO/MgO, computational screening shows that hundreds of potential cubic oxide pairs fit the design principles of immiscible refractory photonics. Extending the concept to other material systems could enable further breakthroughs in a wide range of photonic and energy conversion applications.

Laser surface texturing provides several benefits such as improved tribological behavior of the surface, reduced friction, increased anti-adhesive properties and improved wettability and lubrication applications. Even though, surface topography or surface roughness resulting from laser processing of steel surfaces have been studied in literature, the relation between laser texturing parameters and scale-limited areal surface texture parameters are not as much investigated and correlated. Fiber lasers provide a flexible solution for texturing different materials with different surface structures. In this paper, laser surface processing and texturing of tool steels is considered, and a nanosecond fiber laser system is utilized to scan and texture the surfaces of AISI D2 tool steel under a shield of Argon gas to prevent oxidation. The effects of laser energy density, scan velocity, and strategy on the texture line width and resultant areal surface texture parameters have been investigated. It was found that Argon gas during laser texturing of tool steel helps to achieve not only less heat affected zone but also slightly lower surface roughness indicating that the application of an inert gas requires further investigations.

Chlorine substitution, as an effective and low-cost modification strategy, has been applied in the design of donor and acceptor structures in organic solar cells. We synthesized a series of chlorinated dimerized acceptors to investigate the effect of chlorine numbers and locations on the photovoltaic properties. The results show that the planarity and morphology of DYV-γ-2Cl are greatly improved due to the appropriate numbers and positions of the substituted chlorine atoms. Therefore, the device based on PM6:DYV-γ-2Cl achieves a superior power conversion efficiency (PCE) of 15.54% among the three oligomeric acceptors with optimized molecular planarity and film morphology. This work demonstrated the positive effect of suitable numbers and the substitution positions of chlorines on the molecular arrangement and photovoltaic properties of the corresponding dimerized acceptors.

The two-dimensional (2D)/three-dimensional (3D) heterojunction perovskite solar cell (PSC) has recently been recognized as a promising photovoltaic structure for achieving high efficiency and long-term stability. Rational design of the 2D spacer cation is important to achieve a win–win situation for defects’ passivation and photogenerated carrier extraction. Herein, we carry out first-principles calculation to analyze the dipole moment of phenethylamine-type molecules and their resulting 2D/3D perovskites. Based on the results of theoretical calculation, the dipole moment of 2D cations can be well tuned by varying the number of fluorine atoms on the para-position of the benzene ring, which further determines the interfacial dipole across the 2D/3D heterojunction interface. A high dipole 2D perovskite layer at the interface between the 3D perovskite and hole-transporting material is found to promote charge transport and suppress charge trapping efficiently. As a result, our 2D/3D PSCs exhibit a champion power conversion efficiency over 22% and a fill factor over 83%. Moreover, our solar cells also show a remarkable stability, maintaining 80% of its initial efficiency for more than 1400 h without encapsulation under a 30 ± 5% relative humidity.

Hole transporting materials (HTMs) play a crucial role in achieving highly efficient and stable perovskite solar cells (PSCs). Spiro-typed materials being the most widely used HTMs are commonly utilized with dopants, such as Li-TFSI, to improve their carrier mobility significantly. However, dopants could affect the morphology of hole transporting layer negatively by forming defects and pinholes which restrict the performance of devices. Here, we adopt the extended π-conjugated structures N-ethylcarbazole and dibenzothiophene to substitute the donor group 4-methoxyphenyl of spiro-OMeTAD, devising two novel HTMs, SC and ST, respectively. Notably, SC possesses low crystallinity and good solubility due to the existence of ethyl in side groups, leading to decent miscibility with Li-TFSI to prevent unfavorable phase-separation. The SC-based device delivers the best power conversion efficiency (PCE) of 21.76% which is higher than that of spiro-OMeTAD (20.73%), attributed to the formation of smooth and pinhole-free morphology. Moreover, it exhibits long-term stability and retains over 90% of initial PCE value for more than 30 days without encapsulation in ambient air. In contrast, the ST-based device suffers from dense pinholes induced by its relatively high crystallinity and poor solubility, resulting in a low PCE of 18.18% and inferior stability. Thus, it is effective to modify the side groups in spiro-typed HTMs with specific structures to obtain predictable properties, fabricating PSCs with high efficiency and stability facilely.

Entropy stabilization is a novel materials-design paradigm to realize new compounds with widely tunable properties. However, almost all entropy-stabilized materials so far are either conducting metals or insulating ceramics, with a clear dearth in the semiconducting regime. Here, a new class of the multicationic and -anionic entropy-stabilized chalcogenide alloys based on the (Ge,Sn,Pb)(S,Se,Te) formula are synthesized and characterized experimentally. The configurational entropy from the disorder of both the anion and the cation sublattices reaches a record value of ∼2.2 Rmol–1for the equimolar composition and stabilizes the single-phase solid solution. Theoretical calculations and experiments both show that the synthesized alloys are thermodynamically stable at the growth temperature and kinetically metastable at room temperature, segregating by spinodal decomposition at moderate temperatures. Doping and electronic transport measurements verify that the synthesized materials are ambipolarly dopable semiconductors, which pave the way for the wider adoption of entropy-stabilized chalcogenide alloys in functional applications.

This work initially reports the use of a quite familiar optical phenomenon of colloidal solutions, namely, the Tyndall Effect (TE) as signal readout for highly sensitive colorimetric chemical and biological analysis. Taking gold nanoparticles (GNPs) as a model colloid, the TE-inspired assay (TEA) is developed based on the conversion of a specific recognition event (e.g., the aptamer–analyte binding) into the aggregation of GNPs, leading to a significant TE enhancement. In the TEA, a cheap laser pointer pen is used as a hand-held light source, while a smartphone serves as a portable quantitative reader. The results show that the TE signaling strategy achieves a ∼1000-fold sensitivity improvement compared with the most common surface plasmon resonance signaling method using GNPs. The utility of the TEA is well demonstrated with the inexpensive, rapid, and portable detection of trace levels of analytes ranging from an important small-molecule drug (cocaine, ∼1.5 pM detection limit) to a protein biomarker (interferon-γ, ∼2.2 fM detection limit) and a toxic metal ion (Ag+, ∼1.4 nM detection limit). In addition, as the TE enhancement simply stems from the aggregation of either bare (unmodified) or modified GNPs, the TEA is universally applicable to almost all of the existing GNP-based liquid-phase colorimetric assays. The TEA method developed herein lights a new way for equipment-free point-of-care analysis in various fields including medical diagnosis, food safety evaluation, and environmental monitoring, especially in the resource-poor areas of the world.

We present experimental results confirming extreme quantum confinement in GaN/AlxGa1–xN (x= 0.65 and 1.0) nanowire and planar heterostructures, where the GaN layer thickness is of the order of a monolayer. The results were obtained from temperature- and excitation-dependent and time-resolved photoluminescence measurements. In the GaN/AlN nanowire heterostructure array sample, the measured emission peak at 300 K is ∼5.18–5.28 eV. This is in excellent agreement with the calculated optical gap of 5.23 eV and 160–260 meV below the calculated electronic gap of 5.44 eV, suggesting that the observed emission is excitonic in nature with an exciton binding energy of ∼160–260 meV. Similarly, in the monolayer GaN/Al0.65Ga0.35N planar heterostructure, the measured emission peak at 300 K is 4.785 eV and in good agreement with the calculated optical gap of 4.68 eV and 95 meV below the calculated electronic gap of 4.88 eV. The estimated exciton binding energy is 95 meV and in close agreement with our theoretical calculations. Excitation-dependent and time-resolved photoluminescence data support the presence of excitonic transitions. Our results indicate that deep-ultraviolet excitonic light sources and microcavity devices can be realized with heterostructures incorporating monolayer-thick GaN.

•VPS35 involved in the EVs formation, delivery and secretion process induced by N-terminal Hsp90 inhibitor STA9090 but not C-terminal Hsp90 inhibitor NB and promoted HCC invasion.•Bclaf1 upregulated VPS35 transcription through bZIP DNA binding domain, and upregulation of VPS35 and Bclaf1 levels positively correlates with poorer prognosis and metastasis in HCC.•HSF1 positively correlated with Bclaf1 levels.•Hsp90 inhibitor STA9090 induced EVs promote invasion and metastasis by HSF1-Bclaf1-VPS35-EVs axis in hepatocellular carcinoma.•Bclaf1 down-regulation alleviates Hsp90 inhibitor STA9090 induced VPS35 related extracellular vesicle release and invasion.

Cleft lip and palate are common birth defects resulting from failure of the facial processes to fuse during development. The mammalian grainyhead-like (Grhl1-3) genes play key roles in a number of tissue fusion processes including neurulation, epidermal wound healing and eyelid fusion. One family member, Grhl2, is expressed in the epithelial lining of the first pharyngeal arch in mice at embryonic day (E)10.5, prompting analysis of the role of this factor in palatogenesis. Grhl2-null mice die at E11.5 with neural tube defects and a cleft face phenotype, precluding analysis of palatal fusion at a later stage of development. However, in the first pharyngeal arch of Grhl2-null embryos, dysregulation of transcription factors that drive epithelial-mesenchymal transition (EMT) occurs. The aberrant expression of these genes is associated with a shift in RNA-splicing patterns that favours the generation of mesenchymal isoforms of numerous regulators. Driving the EMT perturbation is loss of expression of the EMT-suppressing transcription factors Ovol1 and Ovol2, which are direct GRHL2 targets. The expression of the miR-200 family of microRNAs, also GRHL2 targets, is similarly reduced, resulting in a 56-fold upregulation of Zeb1 expression, a major driver of mesenchymal cellular identity. The critical role of GRHL2 in mediating cleft palate in Zeb1−/− mice is evident, with rescue of both palatal and facial fusion seen in Grhl2−/−;Zeb1−/− embryos. These findings highlight the delicate balance between GRHL2/ZEB1 and epithelial/mesenchymal cellular identity that is essential for normal closure of the palate and face. Perturbation of this pathway may underlie cleft palate in some patients.