Robust excitonic light emission in 2D tin halide perovskites by weak excited state polaronic effect.

2D perovskites hold immense promise in optoelectronics due to their strongly bound electron-hole pairs (i.e., excitons). While exciton polaron from interplay between exciton and lattice has been established in 2D lead-based perovskites, the exciton nature and behavior in the emerging 2D tin-based perovskites remains unclear. By combining spin-resolved ultrafast spectroscopy and sophisticated theoretical calculations, we reveal 2D tin-based perovskites as genuine excitonic semiconductors with weak polaronic screening effect and persistent Coulomb interaction, thanks to weak exciton-phonon coupling. We determine an excited state exciton binding energy of ~0.18 eV in n = 2 tin iodide perovskites, nearly twice of that in lead counterpart, despite of same large value of ~0.2 eV from steady state measurement. This finding emphasizes the pivotal role of excited state polaronic effect in these materials. The robust excitons in 2D tin-based perovskites exhibit excitation power-insensitive, high-efficiency and color-purity emission, rendering them superior for light-emitting applications.

Coronavirus M protein promotes mitophagy over virophagy by recruiting PDPK1 to phosphorylate SQSTM1 at T138.

Autophagy plays a dual role in coronavirus infection, facilitating the elimination of either proviral components (virophagy) or antiviral factors such as mitochondria (mitophagy), leading to complex mechanisms of immune evasion. Understanding the mechanisms that govern the switch between the autophagic degradation of deleterious or beneficial substrates in coronavirus infection is crucial for developing precise drug targets to treat virus-induced diseases. However, this switch remains largely unknown. Using a dual split-fluorescence assay, we identify PDPK1 as a negative regulator of innate immunity, directing the transition from virophagy to mitophagy through the phosphorylation of SQSTM1 at T138. Remarkably, a PDPK1-targeting peptide inhibits the replication of various RNA viruses by restoring innate immunity through enhanced virophagy and suppressed mitophagy, thereby protecting female mice from lethal infections. These findings underscore the detrimental role of PDPK1 in innate immunity by orchestrating the shift from virophagy to mitophagy, positioning PDPK1 as a promising pharmacological target for effectively combating a broad spectrum of virus infections.

PdSe2/2H-MoTe2 Heterojunction Self-Powered Photodetector: Broadband Photodetection and Linear/Circular Polarization Capability.

In this research, we introduce a PdSe2/2H-MoTe2 heterojunction photodetector that exhibits both broadband self-powered photodetection and linear/circular polarization detection capabilities. It has a broad spectral response range (covering 375-2200 nm) and reaches a peak sensitivity at 532 nm, exhibiting a notable responsivity of 7.3 × 103 A/W and a substantial specific detectivity of 8.5 × 1012 Jones. Even in the near-infrared region of 1310 nm, it still has a high responsivity of 20 A/W. The self-powered photodetection capabilities of the PdSe2/2H-MoTe2 heterojunction are equally impressive, covering a broad range from 375 to 1550 nm, with a responsivity of 243 mA/W, a specific detectivity of 6.46 × 1010 Jones, a fill factor of 0.8, and an external quantum efficiency of 56.73%. Finally, simultaneous implementation of linear/circular polarization detection on the PdSe2/2H-MoTe2 heterojunction provides a powerful solution for near-infrared full-Stokes polarization detectors with high integration, miniaturization, and portability.

Design, Synthesis, and 3D-QASR of Oxazoline Derivatives Containing an S-S Moiety as Potential Acaricide.

To mitigate the detrimental effects of agricultural pest mites on crop yield, an active substructure splicing strategy was employed to modify etoxazole by introducing an S-S moiety. The target products were obtained efficiently via a bilateral disulfurating reagent (DSMO), which was developed by our group. The leaf dip method was used to evaluate the activities of the designed target compounds against the eggs and larvae of the spider mite (Tetranychus cinnabarinus). Most of the target compounds exhibited good efficacy in controlling the larvae and eggs of T. cinnabarinus. Based on these results, a three-dimensional quantitative structure-activity relationship (3D-QSAR) model was established to guide the construction of compound 7l. Notably, compound 7l exhibited a better activity against T. cinnabarinus eggs (LC50 = 0.0035 mg/L) compared to etoxazole (LC50 = 0.2990 mg/L). Greenhouse bioassays indicated that compound 7l exhibits excellent acaricidal activity against egg of T. cinnabarinus, which is better than the etoxazole at 1.0 mg/L. Additionally, some of the compounds showed inhibitory effects against Dickeya zeae (D. zeae), Xanthomonas campestris pv campestris (Xcc), Xanthomonas oryzae pvoryza (Xoo), and Xanthomonas oryzae pvoryzicola (Xoc). Furthermore, compounds 7l not only exhibited relatively potent against Plutella xylostella activities (LC50 = 24.0 mg/L) but also had low toxicity (LC50 > 11.0 µg/bee) to Apis mellifera. In conclusion, the current experimental results suggest that oxazoline derivatives containing an S-S moiety have the potential to serve as lead compounds for the development of novel acaricide agents.

Insights into bioaerosol contamination in the process of mineralized refuse mining: Microbial aerosolization behavior and potential pathogenicity.

The landfill mining process is a main source of anthropogenic bioaerosol release, posing potential risks to the health of occupationally exposed personnel and nearby residents. In this study, microbial aerosolization behavior and potential pathogenicity during the landfill mining process were systematically investigated. The highest concentration of bacterial aerosols was measured in the refuse mining area, with a value of 5968 ± 1608 CFU/m3, while the highest concentration of fungal aerosols was 1196 ± 370 CFU/m3 in the refuse screening area. The bacterial and fungal aerosols were distributed primarily in the particle size ranges of 4.7-7.0 µm and > 7.0 µm, respectively. The pathogenic microbes Arthrobacter, Bacillus, Arthrobotrys and Aspergillus had high bioaerosol aerosolization capacities, with aerosolization indices of 100-329, 31-62, 2-14 and 1-11, respectively, when released from mineralized refuse. There are more than 100 types of pathogenic bacteria in bioaerosols. The microorganisms Lysobacter, Luteimonas and Mycolicibacterium, which carry virulence factor genes (VFGs) (pilG, Rv0440, pilT, etc.), can spread VFGs, aggravate bioaerosol pollution, and threaten the health of workers and nearby residents. This research will help further the understanding of bioaerosol contamination behaviors and potential pathogenicity risks from landfill mining activities.

Two-Orders-of-Magnitude Enhancement of SERS Activity via a Simple Surface Engineering of Quasi-Metal Single-Crystal Frameworks.

Beyond noble metals and semiconductors, quasi-metals have recently been shown to be noteworthy substrates for surface enhanced Raman spectroscopy, and their excellent quasi-metal surface-enhanced Raman spectroscopy (SERS) sensing has demonstrated a wider range of application scenarios. However, the underlying mechanism behind the enhanced Raman activity is still unclear. Here, we demonstrate that surface hydroxyls play a crucial role in the enhancement of the SERS activity of quasi-metal nanostructures. As a demonstration material, quasi-metallic MoO2 single-crystal frameworks rich in surface hydroxyls have been shown to have 100 times higher SERS activity than MoO2 single-crystal frameworks without hydroxyl functionalization, with a Raman enhancement factor of up to 7.6 × 107. Experimental and first-principles density-functional theory calculation results show that the enhanced Raman activity can be attributed to an effective interfacial charge transfer within the MoO2/OH/molecule system.

Study on the Adsorption Law of n-Pentane in Silica Slit Nanopores.

As the main components of shale, inorganic minerals are important carriers for oil and gas adsorption, whose pore structures and surface properties have significant effects on the fluid adsorption capacity. In this study, slit nanopores (SNPs) were constructed by silica. To investigate the microscopic adsorption law of n-pentane in silica, the grand canonical Monte Carlo (GCMC) method was used to simulate the adsorption behaviors of n-pentane in silica nanoparticles. The effects of different surface wettability, pore size, temperature, and pressure values on the adsorption behavior of pentane were discussed, revealing the micro adsorption mechanism of pentane in silica with different pore sizes and wettability and evaluating the degree of oil and gas utilization. The research results indicate that the adsorption capacity of pentane is greatly affected by the temperature under low-pressure conditions. With the increase of the pore size, the adsorption capacity of pentane increases linearly, and the number of adsorbed pentane molecules gradually decreases. The availability of oil and gas increases, and the oil and gas are more easily extracted. As the surface hydrophobicity of minerals increases, the van der Waals force between minerals and pentane also increases, leading to an increase in the number of adsorbed states of pentane. The stronger the hydrophilicity of the wall, the fewer the pentane molecules adsorbed on the surface, which would improve the efficiency of oil and gas extraction. This study provides potential for the development of novel surfactants based on adsorption selectivity.

Single-cell RNA sequencing highlights the immunosuppression of IDO1+ macrophages in the malignant transformation of oral leukoplakia.

Rationale: Immunosuppressive tumor microenvironment (iTME) plays an important role in carcinogenesis, and some macrophage subsets are associated with iTME generation. However, the sub-population characterization of macrophages in oral carcinogenesis remains largely unclear. Here, we investigated the immunosuppressive status with focus on function of a macrophage subset that expressed indoleamine 2,3 dioxygenase 1 (Macro-IDO1) in oral carcinogenesis. Methods: We built a single cell transcriptome atlas from 3 patients simultaneously containing oral squamous cell carcinoma (OSCC), precancerous oral leukoplakia (preca-OLK) and paracancerous tissue (PCA). Through single-cell RNA sequencing and further validation using multicolor immunofluorescence staining and the in vitro/in vivo experiments, the immunosuppressive cell profiles were built and the role of a macrophage subset that expressed indoleamine 2,3 dioxygenase 1 (Macro-IDO1) in the malignant transformation of oral leukoplakia was evaluated. Results: The iTME formed at preca-OLK stage, as evidenced by increased exhausted T cells, Tregs and some special subsets of macrophages and fibroblasts. Macro-IDO1 was predominantly enriched in preca-OLK and OSCC, distributed near exhausted T cells and possessed tumor associated macrophage transformation potentials. Functional analysis revealed the established immunosuppressive role of Macro-IDO1 in preca-OLK and OSCC: enriching the immunosuppression related genes; having an established level of immune checkpoint score; exerting strong immunosuppressive interaction with T cells; positively correlating with the CD8-exhausted. The immunosuppression related gene expression of macrophages also increased in preca-OLK/OSCC compared to PCA. The use of the IDO1 inhibitor reduced 4NQO induced oral carcinogenesis in mice. Mechanistically, IFN-γ-JAK-STAT pathway was associated with IDO1 upregulation in OLK and OSCC. Conclusions: These results highlight that Macro-IDO1-enriched in preca-OLK possesses a strong immunosuppressive role and contributes to oral carcinogenesis, providing a potential target for preventing precancerous legions from transformation into OSCC.

Self-powered temperature-changing system driven by wind energy.

Research on outdoor, mobile, and self-powered temperature-control devices has always been highly regarded. These devices can reduce energy consumption for cooling and heating, and they have broad market prospects. On this basis, a rotary disc-shaped triboelectric nanogenerator (TENG) with a maximum open-circuit voltage of 6913 V, a maximum short-circuit current of 85 µA, and a maximum transferred charge of 1.3 µC was prepared. We synthesized a ferroelectric ceramic composed of 0.15PbTiO3-0.85PbSc0.5Ta0.5O3 (0.15PT-0.85PST), which exhibited excellent electrothermal effects at room temperature. By quenching, the electrothermal effect ( Δ Tmax) and energy harvesting properties of the device were 1.574 K and 0.542 J/cm3, respectively. Then, for the first time, we proposed a self-powered temperature quantification control system with a rotary disc-shaped TENG. This device effectively harnessed wind and water energy, in addition to other types of energy. The system consisted of energy collecting cups, a rotating disc-shaped FEP-rabbit fur TENG, a circuit management module, and a ferroelectric ceramic chip array. Through the circuit management module, the system converted external wind energy into a high-voltage electric field at the two ends of the 0.15PT-0.85PST ceramic chip to fully stimulate the electrothermal effect. At a speed of 200 rpm, the temperature change in the insulated cup within 276 s was 0.49 K, and the volume of the insulated cup was 300 times greater than that of the 0.15PT-0.85PST ceramic chip. Compared with the results reported in previous work, the cooling and heating times were both reduced by 31%, and the temperature changes for both cooling and heating increased by 81%. Moreover, the heating and cooling temperatures of the device optimized on this basis were increased to 1.19 K and 0.93 K, respectively. The great improvement in the temperature variation performance confirmed the great potential of the device for commercialization. This research could serve as a reference for reducing energy consumption for cooling and heating, and it meets the international energy policies of carbon dioxide emission peaking and carbon neutrality.

A flexible resistive strain gauge with reduced temperature effect via thermal expansion anisotropic composite substrate.

Strain gauge plays vital roles in various fields as structural health monitoring, aerospace engineering, and civil infrastructure. However, traditional flexible strain gauge inevitably brings the pseudo-signal caused by the substrate temperature effect and determines its accuracy. Here, we present an anisotropic composite substrate designed to modify the thermal expansion performance via Micro-electro-mechanical System (MEMS) technology, which facilitates the development of strain gauges that are minimally affected by substrate temperature-induced effect. Compared to the isotropic flexible substrate, the simulated expansion displacement in the thermal insensitive direction is reduced by 53.6% via introducing an anisotropic thermal expansion structure. The developed strain gauge exhibits significantly reduced sensitivity to temperature-induced effect, with a temperature coefficient of resistance decreasing from 87.3% to 10%, along with a notable 47.1% improvement in TCR stability. In addition, the strain gauge displays a sensitivity of 1.99 and boasts a wide strain operational range of 0-6000 µÎµ, while maintaining excellent linearity. Furthermore, stress response conducted on a model of an aircraft wing illustrates the rapid monitoring of the strain gauge, which can detect strain as low as 100 µÎµ. This study strongly highlights the potential applicability of the developed strain gauge in the aircraft, ships, and bridges for monitoring stress.

Genome-wide analysis of long non-coding RNAs involved in the fruit development process of Cucumis melo Baogua.

Melon (Cucumis melo L.) is a horticultural crop that is planted globally. Cucumis melo L. cv. Baogua is a typical melon that is suitable for studying fruit development because of its ability to adapt to different climatic conditions. Long non-coding RNAs (lncRNAs) are a class of non-coding RNAs longer than 200 nucleotides, which play important roles in a wide range of biological processes by regulating gene expression. In this study, the transcriptome of the Baogua melon was sequenced at three stages of the process of fruit development (14 days, 21 days, and 28 days) to study the role of lncRNAs in fruit development. The cis and trans lncRNAs were subsequently predicted and identified to determine their target genes. Notably, 1716 high-confidence lncRNAs were obtained in the three groups. A subsequent differential expression analysis of the lncRNAs between the three groups revealed 388 differentially expressed lncRNAs. A total of 11 genes were analyzed further to validate the transcriptome sequencing results. Interestingly, the MELO3C001376.2 and MSTRG.571.2 genes were found to be significantly (P < 0.05) downregulated in the fruits. This study provides a basis to better understand the functions and regulatory mechanisms of lncRNAs during the development of melon fruit.

Designing Highly Efficient Electrocatalyst for ORR and OER Based on Nb2CO2 MXene: The Role of Transition Metals and N-Doping Content.

Finding efficient and stable electrocatalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is imperative for advancing zinc-air batteries. Herein, the effect of transition metal anchored on Nb2CO2 with different N content to form TM-Nx-Nb2CO2 on the catalytic activity of ORR and OER is investigated by density functional theory. Among all the designed TM-Nx-Nb2CO2, Pt-N12.50%-Nb2CO2, Pt-N37.50%-Nb2CO2, Pt-N50.00%-Nb2CO2, Pd-N68.75%-Nb2CO2, and Pd-N100%-Nb2CO2 are excellent ORR electrocatalysts with ηORR values of 0.38, 0.36, 0.38, 0.38, and 0.34 V, respectively. Rh-Nb2CO2, Rh-N12.50%-Nb2CO2, Rh-N31.25%-Nb2CO2, Rh-N37.50%-Nb2CO2, Rh-N50.00%-Nb2CO2, Pt-N50.00%-Nb2CO2, Rh-N68.75%-Nb2CO2, and Rh-N81.25%-Nb2CO2 are excellent OER electrocatalysts with ηOER values of 0.33, 0.37, 0.34, 0.36, 0.37, 0.34, 0.38, and 0.33 V, respectively. Notably, Rh-Nb2CO2 and Pt-N50.00%-Nb2CO2 exhibit outstanding ORR and OER bifunctional catalytic activity with potential gap values of 0.80 and 0.72 V, respectively, which are higher than the activities of most reported bifunctional catalysts. Furthermore, electronic structure analysis indicates that the moderate adsorption strength of oxygen-containing intermediates on active centers is crucial for achieving highly active bifunctional catalysts for ORR and OER. This study provides a strategy for the design of novel ORR and OER catalysts using 2D MXene materials.

Genetic analysis and preliminary mapping by BSA-seq of the CmSR gene regulating the spotted rind trait in melon (Cucumis melo L.).

Melon (Cucumis melo L.) is an economically important horticultural crop. Spotted rind at maturity is an important appearance quality trait in melons. However, the gene controlling this trait remains unknown. In this study, the inheritance pattern of this trait was explored, and the candidate gene underlying this trait was also successfully identified. Genetic analysis showed that a single dominant gene, Cucumis melo Spotted Rind (CmSR), regulates the spotted rind trait. A preliminary genetic mapping analysis was conducted based on a BSA-seq approach. The CmAPRR2 gene was identified to be linked with the spotted rind trait and was located on the short arm of chromosome 4. It harbored two single-nucleotide mutations (chr4: 687014 G/A and chr4: 687244 C/A) in the non-spotted line 'Yellow 2', which may result in the alternative splicing of the transcript and an amino acid change in the respective protein, from proline to glutamine, respectively. Moreover, marker SNP687014-G/A was developed and co-segregated with the spotted rind trait. Therefore, it is speculated that the CmAPRR2 gene may be involved in the regulation of the spotted rind trait in melon. This study provides a theoretical foundation for further research on the gene regulatory mechanism of the rind color in melon.

The impact of cue and preparation prompts on attention guidance in goal-directed tasks.

Introduction: In goal-directed tasks, visual prompts before the appearance of goals can make people ready in advance, which helps them to complete the movement better, and the presentation type of the visual prompt is very important. In previous studies, it has not been clear how different types of visual prompts guide attention in goal-directed tasks. Methods: According to the characteristics of goal-directed tasks, our research designed three different prompts: the cue prompt (featuring static arrow), the preparation prompt (involving dynamic countdown), and the combination prompt of cue and preparation information (simultaneously incorporating arrow and countdown). We used event-related potential components (CNV and P300) and graph theory indicators (clustering coefficient and characteristic path length) under the brain function connection to analyze the attention state of the brain. Results: The results showed that the combination prompts better guided the participants' sustained attention during the prompt stage, making them well prepared for the movement. Thus, after the target appeared, the participants had better executive control and achieved a faster response to the target. However, under the combination prompt, the participants consumed more attention resources during the prompt stage. Discussion: We believe that for the participants with impaired cognitive function, cue prompts or preparation prompts can be considered, which also play a role in guiding the participants' attention and helping them make motor preparations when less attention resources are consumed. This study provides a neurophysiological and behavioral foundation for the design of visual prompts in goal-directed tasks.

Size-dependent effect on controllable release and field insecticidal efficacy of diamide insecticide polylactic acid microspheres delivery systems against Ostrinia nubilalis.

New nano/microcarriers of pesticides represent a highly promising novel field for sustainable pest management. However, despite extensive laboratory research, few studies on the design and evaluation of nanopesticides for field applications exist. In this study, we present a straightforward and green synthetic method of ultrasonic-assisted and hydrogen-bonded self-assembly at the oil-water interface for the synthesis of polylactic acid (PLA) microspheres encapsulating chlorantraniliprole (CAP), with precise control over the size of the microspheres. The resulting CAP-loaded PLA microspheres (CAP-PLA MS) exhibit both high pesticide encapsulation efficiency and stability in natural environments. It has been determined that non-Fickian diffusion mainly controls pesticide release, thus enabling dynamic control over molecular transport speeds. Importantly, our functional CAP-PLA MS demonstrates superior sustained pesticide release performance under both laboratory and field conditions while maintaining better exceptional insecticidal efficacy than normal CAP in controlling O. nubilalis at a concentration of 30 or 45 g/ha. Consequently, we propose that our functional PLA microspheres could serve as ideal pesticide carriers in the sustained treatment of O. nubilalis.

Wafer-Scale Growth and Transfer of High-Quality MoS2 Array by Interface Design for High-Stability Flexible Photosensitive Device.

Transition metal disulfide compounds (TMDCs) emerges as the promising candidate for new-generation flexible (opto-)electronic device fabrication. However, the harsh growth condition of TMDCs results in the necessity of using hard dielectric substrates, and thus the additional transfer process is essential but still challenging. Here, an efficient strategy for preparation and easy separation-transfer of high-uniform and quality-enhanced MoS2 via the precursor pre-annealing on the designed graphene inserting layer is demonstrated. Based on the novel strategy, it achieves the intact separation and transfer of a 2-inch MoS2 array onto the flexible resin. It reveals that the graphene inserting layer not only enhances MoS2 quality but also decreases interfacial adhesion for easy separation-transfer, which achieves a high yield of ≈99.83%. The theoretical calculations show that the chemical bonding formation at the growth interface has been eliminated by graphene. The separable graphene serves as a photocarrier transportation channel, making a largely enhanced responsivity up to 6.86 mA W-1, and the photodetector array also qualifies for imaging featured with high contrast. The flexible device exhibits high bending stability, which preserves almost 100% of initial performance after 5000 cycles. The proposed novel TMDCs growth and separation-transfer strategy lightens their significance for advances in curved and wearable (opto-)electronic applications.

Adeno-associated-virus-mediated delivery of CRISPR-CasRx induces efficient RNA knockdown in the mouse testis.

Rationale: In male mammals, many developmental-stage-specific RNA transcripts (both coding and noncoding) are preferentially or exclusively expressed in the testis, where they play important roles in spermatogenesis and male fertility. However, a reliable platform for efficiently depleting various types of RNA transcripts to study their biological functions during spermatogenesis in vivo has not been developed. Methods: We used an adeno-associated virus serotype nine (AAV9)-mediated CRISPR-CasRx system to knock down the expression of exogenous and endogenous RNA transcripts in the testis. Virus particles were injected into the seminiferous tubules via the efferent duct. Using an autophagy inhibitor, 3-methyladenine (3-MA), we optimized the AAV9 transduction efficiency in germ cells in vivo. Results: AAV9-mediated delivery of CRISPR-CasRx effectively and specifically induces RNA transcripts (both coding and noncoding) knockdown in the testis in vivo. In addition, we showed that the co-microinjection of AAV9 and 3-MA into the seminiferous tubules enabled long-term transgene expression in the testis. Finally, we found that a promoter of Sycp1 gene induced CRISPR-CasRx-mediated RNA transcript knockdown in a germ-cell-type-specific manner. Conclusion: Our results demonstrate the efficacy and versatility of the AAV9-mediated CRISPR-CasRx system as a flexible knockdown platform for studying gene function during spermatogenesis in vivo. This approach may advance the development of RNA-targeting therapies for conditions affecting reproductive health.

Transcriptomics-based analysis of Macrobrachium rosenbergii growth retardation.

Macrobrachium rosenbergii is an economically important crustacean in many parts of the world, but in recent years, growth retardation has become an increasingly serious issue. While the underlying causes remain unclear, this has inevitably impacted on aquaculture and production outputs. In this study, gill, hepatopancreas, and muscle tissue samples from M. rosenbergii, with distinct growth differences, underwent transcriptome sequencing and bioinformatics analyses using high-throughput sequencing. In total, 59,796 unigenes were annotated. Differential expression analyses showed that the most differentially expressed genes (DEGs) were screened in gill tissue (1790 DEGs). In muscle and hepatopancreas tissues, 696 and 598 DEGs were screened, respectively. These DEGs were annotated to Kyoto Encyclopedia of Genes and Genomes pathways, which identified several significantly enriched pathways related to growth metabolism, such as PI3K-AKT, glycolysis/gluconeogenesis, and starch and sucrose metabolism. These results suggest that low growth metabolism levels may be one cause of M. rosenbergii growth retardation. Our data provide support for further investigations into the causes and molecular mechanisms underpinning growth retardation in M. rosenbergii.

Robust and Efficient Out-of-Plane Exciton Transport in Two-Dimensional Perovskites via Ultrafast Förster Energy Transfer.

Two-dimensional (2D) perovskites, comprising inorganic semiconductor layers separated by organic spacers, hold promise for light harvesting and optoelectronic applications. Exciton transport in these materials is pivotal for device performance, often necessitating deliberate alignment of the inorganic layers with respect to the contacting layers to facilitate exciton transport. While much attention has focused on in-plane exciton transport, little has been paid to out-of-plane interlayer transport, which presumably is sluggish and unfavorable. Herein, by time-resolved photoluminescence, we unveil surprisingly efficient out-of-plane exciton transport in 2D perovskites, with diffusion coefficients (up to ∼0.1 cm2 s-1) and lengths (∼100 nm) merely a few times smaller or comparable to their in-plane counterparts. We unambiguously confirm that the out-of-plane exciton diffusion coefficient corresponds to a subpicosecond interlayer exciton transfer, governed by the Förster resonance energy transfer (FRET) mechanism. Intriguingly, in contrast to temperature-sensitive intralayer band-like transport, the interlayer exciton transport exhibits negligible temperature dependence, implying a lowest-lying bright exciton state in 2D perovskites, irrespective of spacer molecules. The robust and ultrafast interlayer exciton transport alleviates the constraints on crystal orientation that are crucial for the design of 2D perovskite-based light harvesting and optoelectronic devices.

Revisiting the Structure and Bonding in Li5H6- and the Exploration of Reactivity: Planar Pentacoordinate Hydrogen.

Recently, Guha and co-workers (Sarmah, K.; Kalita, A.; Purkayastha, S.; Guha, A. K. Pushing The Extreme of Multicentre Bonding: Planar Pentacoordinate Hydride. Angew. Chem. Int. Ed. 2024, e202318741) reported a highly intriguing bonding motif: planar pentacoordinate hydrogen (ppH) in Li5H6-, featuring C2v symmetry in the singlet state with two distinct H-Li (center-ring) bond distances. We herein revisited the potential energy surface of Li5H6- by using a target-oriented genetic algorithm. Our investigation revealed that the lowest-energy structure of Li5H6- exhibits a ppH configuration with very high D5h symmetry and a 1A1' electronic state. We did not find any electronic effect like Jahn-Teller distortion that could be responsible for lowering its symmetry. Moreover, our calculations demonstrated significant differences in the relative energies of other low-lying isomers. An energetically very competitive planar tetracoordinate hydrogen (ptH) isomer is also located, but it corresponds to a very shallow minimum on the potential energy surface depending on the used level of theory. Chemical bonding analyses, including AdNDP and EDA-NOCV, uncover that the optimal Lewis structure for Li5H6- involves H- ions stabilized by the Li5H5 crown. Surprisingly, despite the dominance of electrostatic interactions, the contribution from covalent bonding is also significant between ppH and the Li5H5 moiety, derived from H-(1s) → Li5H5 σ donation. Magnetically induced current density analysis revealed that due to minimal orbital overlap and the highly polar nature of the H-Li covalent interaction, the ppH exhibits local diatropic ring currents around the H centers, which fails to result in a global aromatic ring current. The coordination of Li5H6- with Lewis acids, BH3 and BMe3, instantly converts the ppH configuration to (quasi) ptH. These Lewis acid-bound ptH complexes show high electronic stability and high thermochemical stability against dissociation and, therefore, will be ideal candidates for the experimental realization.