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Abstract Spodoptera frugiperda is a highly polyphagous pest worldwide with a wide host range that causes serious losses to many economically important crops. Recently, insect-microbe associations have become a hot spot in current entomology research, and the midgut microbiome of S. frugiperda has been investigated, while the effects of cruciferous vegetables remain unknown. In this study, the growth of S. frugiperda larvae fed on an artificial diet, Brassica campestris and Brassica oleracea for 7 days was analyzed. Besides, the microbial community and functional prediction analyses of the larval midguts of S. frugiperda fed with different diets were performed by high-throughput sequencing. Our results showed that B. oleracea inhibited the growth of S. frugiperda larvae. The larval midgut microbial community composition and structure were significantly affected by different diets. Linear discriminant analysis effect size (LEfSe) suggested 20 bacterial genera and 2 fungal genera contributed to different gut microbial community structures. The functional classification of the midgut microbiome analyzed by PICRUSt and FUNGuild showed that the most COG function categories of midgut bacterial function were changed by B. oleracea, while the guilds of fungal function were altered by B. campestris significantly. These results showed that the diversity and structure of the S. frugiperda midgut microbial community were affected by cruciferous vegetable feeding. Our study provided a preliminary understanding of the role of midgut microbes in S. frugiperda larvae in response to cruciferous vegetables.

Herein, we demonstrate an optimization of dye-sensitized solar cells (DSSCs) through the development of single-layer and double-layer configurations. Focusing on the incorporation of brookite and anatase phases in varying ratios, the study aims to determine the optimal composition for enhanced photovoltaic performance. The active layer, composed of anatase- and brookite-TiO2 nanoparticles, is further modified with a scattering layer comprising a mixture of anatase nanoparticles and brookite-TiO2 in the form of nanocube or rice-like particles. The synthesis of TiO2 nanostructures with various morphologies and phase compositions and their subsequent application in single-layer and double-layer DSSCs are presented. The results highlight the superior light-harvesting capabilities achieved through the strategic incorporation of brookite phase into the anatase phase, emphasizing the importance of optimizing the anatase: brookite ratio. The single-layer DSSCs exhibit a peak efficiency of 8.73%, achieved with a composition of 30 wt.% brookite and 70 wt.% anatase at a thickness of 15 μ ms. In the context of double-layer DSSCs, the combined optimization of the active layer composition, scattering layer morphology, and utilization of anatase nanoparticles leads to a remarkable efficiency of 9.18%. These findings underscore the critical role of composition and morphology in enhancing the performance of DSSCs, showcasing the potential for brookite-based DSSCs in solar energy conversion. [ABSTRACT FROM AUTHOR]

Organic electrode materials are gaining increased attention in energy storage applications, but often encounter challenges such as low capacity and poor cycling stability. This paper explores the utilization of a 1‐D coordination polymer, copper(II)‐2,5‐dihydroxy‐1,4‐benzoquinone (Cu‐DHBQ), as a cathode material for Li‐ion batteries for the first time. Cu‐DHBQ is air‐stable, devoid of coordinated water molecules, and possesses a high theoretical capacity of 266 mAh g−1. With an optimal sodium alginate (SA) binder content of 25 wt%, the Cu‐DHBQ cathode demonstrates a notable initial capacity of 214 mAh g−1 and outstanding cycling stability, retaining 210 mAh g−1 (98% capacity retention) after 200 cycles at a current rate of 100 mA g−1. A comprehensive investigation into the capacity fading mechanisms, the bonding capability of the SA binder, and the interactions between Cu‐DHBQ and SA is conducted using scanning electron microscope (SEM), peel tests, and Fourier transform infrared spectroscopy (FTIR), respectively. Additionally, the electrochemical reaction mechanisms of Cu‐DHBQ are examined using ex situ X‐ray photoelectron spectroscopy (XPS) and FTIR. These findings offer valuable insights into understanding the electrochemical properties of coordination polymers and metal‐organic frameworks based on DHBQ, shedding light on their potential as materials for battery electrodes. [ABSTRACT FROM AUTHOR]

Optoelectronic synapses with information sensing, processing, and memory function are promoting the development of artificial visual perception systems. However, optoelectronic synapses' relatively inferior optoelectronic performance impedes their application in complex neuromorphic computing. Herein, optoelectronic synapses based on 3D graphene/molybdenum disulfide (MoS2) heterostructure field‐effect transistors are developed by using the double stress layer self‐rolled‐up method. The graphene, with excellent electrical properties, enhances the carrier transport capacity of the device. The unique continuous photoconductivity of MoS2 is suitable for simulating various synaptic nerve morphological functions. Meanwhile, the 3D resonant microcavity is added to enhance the optical field and make the device polarization sensitive, which reveals more intangible features of objects. The device demonstrates room‐temperature photodetection at ultraviolet, visible, near‐infrared, and mid‐infrared regions, with photoresponsivity up to 105 A W−1 at 590 nm. Furthermore, multiple synaptic neuromorphic functions, such as inhibitory postsynaptic current, paired‐pulse facilitation, short‐term depression, and long‐term depression, are successfully emulated. Here a new concept is provided for designing high‐performance optoelectronic synapses with polarization sensitivity and excellent potential in artificial intelligence is shown. [ABSTRACT FROM AUTHOR]

Flexible temperature sensors based on π–conjugated polymers are well‐suited for diverse applications, including food packaging and human health monitoring. Herein, novel dihydropyrazine (DHP)‐based polymers designed for the development of flexible temperature sensors are introduced. The DHP‐based polymers are synthesized via direct arylation polymerization, eliminating toxic byproducts. Polymers with carboxylate potassium salt side chains, which exhibit high solubility in green solvents like water and alcohol are obtained via post‐polymerization hydrolysis of carboxylate ester chains. Furthermore, a post‐deposition treatment converts the carboxylate potassium salt side chains into carboxylic acid side chains, resulting in highly solvent‐resistant polymers. Notably, these DHP‐based polymers exhibit moderate electrical conductivity in the range of ≈10−4 to 10−1 S cm−1 without the need for additional dopants. Resistor‐type temperature sensors based on the self‐doped DHP‐based polymers, processed with ethylene glycol (EG) on flexible polyethylene terephthalate (PET) substrates via blade coating, demonstrate an impressive temperature coefficient of resistance (TCR) of up to −1.5% °C−1 (20–60 °C) and outstanding long‐term stability under ambient conditions. This work presents a well‐founded design of π–conjugated polymers that simultaneously fulfill performance, stability, processability, and cost criteria, paving the way for practical applications of flexible and printable temperature sensors. [ABSTRACT FROM AUTHOR]

The molybdenum disulfide (MoS2)-based photodetectors are facing two challenges: the insensitivity to polarized light and the low photoresponsivity. Herein, three-dimensional (3D) field-effect transistors (FETs) based on monolayer MoS2 were fabricated by applying a self–rolled-up technique. The unique microtubular structure makes 3D MoS2 FETs become polarization sensitive. Moreover, the microtubular structure not only offers a natural resonant microcavity to enhance the optical field inside but also increases the light-MoS2 interaction area, resulting in a higher photoresponsivity. Photoresponsivities as high as 23.8 and 2.9 A/W at 395 and 660 nm, respectively, and a comparable polarization ratio of 1.64 were obtained. The fabrication technique of the 3D MoS2 FET could be transferred to other two-dimensional materials, which is very promising for high-performance polarization-sensitive optical and optoelectronic applications.

The progressive reduction in feature size presents significant challenges such as crosstalk, heat dissipation, and high-power consumption, which impede the advancement of Moore's Law. To overcome the limitations of silicon materials, it is crucial to identify subsequent iterations of innovative semiconductor materials or alternative structures. The integration of two-dimensional (2D) materials and three-dimensional (3D) structures offers a promising platform for exploring novel photodetectors and alternative pathways toward "More than Moore" technologies. In this study, we present a comprehensive evaluation of the underlying mechanisms governing the formation of diverse 3D structures, along with their corresponding preparation methodologies. We focus our evaluation on the distinctive optical properties arising from the incorporation of a self-rolled-up 3D structure into 2D materials and heterojunctions photodetector. Finally, we address some of the challenges and outlook that persist in the development and application of 3D-structured photodetectors based on 2D materials. [ABSTRACT FROM AUTHOR]

Sensitive solar-blind ultraviolet (UV) photodetectors are important to various military and civilian applications, such as flame sensors, missile interception, biological analysis, and UV radiation monitoring below the ozone hole. In this paper, a solar-blind UV photodetector based on a buried-gate graphene field-effect transistor (GFET) decorated with titanium dioxide (TiO2) nanoparticles (NPs) was demonstrated. Under the illumination of a 325-nm laser (spot size ~2 μm) with a total power of 0.35 μW, a photoresponsivity as high as 118.3 A/W was obtained, at the conditions of zero gate bias and a source-drain bias voltage of 0.2 V. This photoresponsivity is over 600 times higher than that of a recently reported solar-blind UV photodetector based on graphene/vertical Ga2O3 nanowire array heterojunction (0.185 A/W). Experiments showed that the photoresponsivity of the TiO2 NPs decorated GFET photodetectors can be further enhanced by increasing the source-drain bias voltage or properly tuning the gate bias voltage. Furthermore, the photoresponse time of the TiO2 NPs decorated GFET photodetectors can also be tuned by the source-drain bias and gate bias. This study paves a simple and feasible way to fabricate highly sensitive, cost-efficient, and integrable solar-blind UV photodetectors.

Various types of Lewis bases have been employed to enhance the performance and stability of perovskite solar cells (PSCs) by passivating the active layer. The cyano (CN) group is a weak Lewis base, the effect of which on the passivation of the perovskite layer is unclear. In this study, we employed simple CN-containing compounds, specifically three isomers of dicyanobenzene (DCB) (1,2-DCB, 1,3-DCB, and 1,4-DCB), as passivation agents for the perovskite layer. Our investigation revealed that these compounds exhibited notable interactions with the perovskite film. They effectively removed residual lead iodide, enhanced crystallinity, enlarged perovskite grain size, and reduced trap density. Consequently, these enhancements resulted in a significant increase in the power conversion efficiency (PCE) and ambient storage stability of the passivated PSCs. Among the three DCB isomers, 1,3-DCB demonstrated the most effective passivation, leading to a remarkable increase in PCE, with a maximum of 21.07%, compared to a PCE of 18.33% for the non-passivated cell. These results confirm that the basic cyano (CN) group efficiently interacts with Pb2+ ions and suggest that CN-containing compounds may represent a promising class of passivation agents for achieving high-performance and stable PSCs. [ABSTRACT FROM AUTHOR]