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The electrochemical CO2reduction reaction (CO2RR) into high-value carbon compounds such as CO and HCOOH is a promising strategy for the utilization and conversion of emitted CO2. However, the selectivity of the CO2RR for HCOOH is typically less than 90% and operates within a narrow voltage range, which limits its practical application. Herein, we propose a novel heterostructural aerogel as a highly efficient electrocatalyst for CO2RR to HCOOH. This catalyst consists of Cu–Sn–Oxsolid solutions embedded in a reduced graphene oxide matrix (Cu–Sn–Ox/rGO). The incorporation of Cu2+into the SnO2matrix enhances HCOOH production by improving the adsorption of the *OCHO intermediate and inhibiting H2evolution, as confirmed by in situmeasurements and computational studies. As a result, Cu–Sn–Ox/rGO achieves a remarkable Faradaic efficiency (FE) of up to 91.4% for HCOOH and maintains high selectivity over a broad operating voltage range (−0.8 to −1.1 V). Additionally, the assembled Zn–CO2batteries demonstrated an excellent power density of 1.14 mW/cm2and exceptional stability for over 25 h.

An inner Helmholtz plane (IHP) structure regulation strategy can be achieved by low-cost and non-toxic maltitol additive; hence the HER, corrosive, and dendrite issues in aqueous Zn-based batteries have been effectively restrained.

Excitonic insulators are long-sought-after quantum materials predicted to spontaneously open a gap by the Bose condensation of bound electron–hole pairs, namely, excitons, in their ground state. Since the theoretical conjecture, extensive efforts have been devoted to pursuing excitonic insulator platforms for exploring macroscopic quantum phenomena in real materials. Reliable evidence of excitonic character has been obtained in layered chalcogenides as promising candidates. However, owing to the interference of intrinsic lattice instabilities, it is still debatable whether those features, such as the charge density wave and gap opening, are primarily driven by the excitonic effect or by the lattice transition. Herein, we develop an intercalation chemistry strategy for obtaining a novel charge-transfer excitonic insulator in organic–inorganic superlattice interfaces that serves as an ideal platform to decouple the excitonic effect from the lattice effect. In this system, we observe a narrow excitonic gap, formation of a charge density wave without periodic lattice distortion, and metal–insulator transition, providing visualized evidence of exciton condensation occurring in thermal equilibrium. Our findings identify self-assembly intercalation chemistry as a new strategy for developing novel excitonic insulators.

The development of an ultralow-Pt catalyst layer (CL) without sacrificing proton-exchange membrane (PEM) fuel cell performance and durability is urgently needed to boost fuel cell commercialization. Besides material development, advanced CL microstructure design is required to ensure optimal multi-physics transfer and enhanced electrochemical surface area (ECSA). However, this is largely hindered by current poor understanding of the complex “gas-liquid-heat-electron-proton” transfers, in conjunction with the electrochemical reactions, and is also greatly influenced by the temporal CL microstructure evolution during long-term operation. Herein, we present several important research and development directions after critically examining the multi-physics transfer in fresh CLs and the microstructure evolution of degraded CLs. This knowledge is essential to designing and fabricating ultralow-Pt CLs for next-generation cost-effective, high-performance, and durable PEM fuel cells and to meet the urgent need for development of new research tools, including pore- and cell-scale models, experimental methods, machine learning algorithms, and their rational combinations.

Thepotential of organic semiconductors(OSC) in forming power devices has been preliminarily demonstrated recently for their high breakdown performance. As one kind of narrow bandwidth semiconductor, the application of which in the power realm is also limited by its sensitivity to ambient temperature and self-heating effect. In this letter, the thermal stability of breakdown characteristics in the lateral drift region organic field transistor(LDR-OFET) is quantitatively and qualitatively explored. By employing the simple spin-coating process, the fabricated LDR-OFETs consist of a diketopyrrolopyrrole-based polymer(DPPT-TT) layer and a Poly (methyl methacrylate)(PMMA) layer as the semiconductor active layer and insulator layer, respectively. Based on the fabricated devices, the good thermal stability of OSC-based lateral power devices is observed. For the temperature ranges from 300-450K, neither the ambient temperature fluctuation nor the self-heating effect results in thermal runaway, making the copolymer OSC-based power devices capable of maintaining their off-state breakdown performance in a wide temperature range. Such a stable avalanche-like breakdown performance indicates the outstanding potential of OSC-based devices in the power realm.

Ultrasensitive sensing to trace atomic and molecular analytes has gained interest for its intimate relation to industrial sectors and human lives. One of the keys to ultrasensitive sensing for many analytical techniques lies in enriching trace analytes onto well-designed substrates. However, the coffee ring effect, nonuniform distribution of analytes onto substrates, in the droplet drying process hinders the ultrasensitive and stable sensing onto the substrates. Here, we propose a substrate-free strategy to suppress the coffee ring effect, enrich analytes, and self-assemble a signal-amplifying (SA) platform for multimode laser sensing. The strategy involves acoustically levitating and drying a droplet, mixed with analytes and core–shell Au@SiO2nanoparticles, to self-assemble an SA platform. The SA platform with a plasmonic nanostructure can dramatically enrich analytes, enabling enormous spectroscopic signal amplification. Specifically, the SA platform can promote atomic detection (cadmium and chromium) to the 10–3mg/L level by nanoparticle-enhanced laser-induced breakdown spectroscopy and can promote molecule detection (rhodamine 6G) to the 10–11mol/L level by surface-enhanced Raman scattering. All in all, the SA platform, self-assembled by acoustic levitation, can intrinsically suppress the coffee ring effect and enrich trace analytes, enabling ultrasensitive multimode laser sensing.

Currently, the development of calcium-ion batteries (CIBs) is still in its infancy and greatly plagued by the absence of satisfactory cathode materials and compatible electrolytes. Herein, an acetonitrile–water hybrid electrolyte is first developed in CIB chemistry, in which, the strong lubricating and shielding effect of water solvent significantly boosts the swift transport of bulky Ca2+, thus contributing to large capacity storage of Ca2+in layered vanadium oxides (Ca0.25V2O5·nH2O, CVO). Meanwhile, the acetonitrile component noticeably suppresses the dissolution of vanadium species during repeated Ca2+-ion uptake/release, endowing the CVO cathode with a robust cycle life. More importantly, spectral characterization and molecular dynamics simulation confirm that the water molecules are well stabilized by the mutual hydrogen bonding with acetonitrile molecules (O–H···N), endowing the aqueous hybrid electrolyte with high electrochemical stability. By using this aqueous hybrid electrolyte, the CVO electrode shows a high specific discharge capacity of 158.2 mAh g–1at 0.2 A g–1, an appealing capacity of 104.6 mAh g–1at a high rate of 5 A g–1, and a capacity retention of 95% after 2000 cycles at 1.0 A g–1, which is a record-high performance for CIBs reported so far. A mechanistic study exemplifies the reversible extraction of Ca2+from the gap of VO polyhedral layers, which are accompanied by the reversible V–O and V–V skeleton change as well as reversible variation of layer spacing. This work constitutes a major advance in developing high-performance Ca-ion batteries.

Aerial access networks have been envisioned as a promising 6G solution to enhance the ground communication systems in both coverage and capacity. To better utilize the spectrum and fully explore different channel characteristics, this paper constructs an integrated network comprising the High Altitude Platform (HAP) and Unmanned Air Vehicles (UAVs) with the Non-Orthogonal Multiple Access (NOMA) technology. In order to improve the transmission quality of images and videos, a power management scheme is proposed to minimize the distortion of the transmissions from the HAP and UAVs to the terminals. The power control is formulated as a non-convex problem constrained by the maximal transmit power and the minimal terminal rate requirements. The variable substitution and the first-order Tailor’s expansion is used to transform it into a sequence of convex problems, which are subsequently solved through the gradient projection method. Simulation demonstrates the signal distortion and error rate improvement achieved by the proposed algorithm.

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Embedded memory, which heavily relies on the manufacturing process, has been widely adopted in various industrial applications. As the field of embedded memory continues to evolve, innovative strategies are emerging to enhance performance. Among them, resistive random access memory (RRAM) has gained significant attention due to its numerous advantages over traditional memory devices, including high speed (<1 ns), high density (4 F2·n−1), high scalability (∼nm), and low power consumption (∼pJ). This review focuses on the recent progress of embedded RRAM in industrial manufacturing and its potential applications. It provides a brief introduction to the concepts and advantages of RRAM, discusses the key factors that impact its industrial manufacturing, and presents the commercial progress driven by cutting-edge nanotechnology, which has been pursued by many semiconductor giants. Additionally, it highlights the adoption of embedded RRAM in emerging applications within the realm of the Internet of Things and future intelligent computing, with a particular emphasis on its role in neuromorphic computing. Finally, the review discusses the current challenges and provides insights into the prospects of embedded RRAM in the era of big data and artificial intelligence.

As a typical correlated metal oxide, vanadium dioxide (VO2) shows specific metal–insulator transition (MIT) properties and demonstrates great potential applications in ultrafast optoelectronic switch, resistive memory, and neuromorphic devices. Effective control of the MIT process is essential for improving the device performance. In the current study, we have first proposed a photoassisted ion-doping method to modulate the phase transition of the VO2layer based on the photovoltaic effect and electron–ion synergic doping in acid solution. Experimental results show that, for the prepared n-VO2/p-GaN nanojunction, this photoassisted strategy can effectively dope the n-VO2layer by H+, Al3+, or Mg2+ions under light radiation and trigger consecutive insulator–metal–insulator transitions. If combined with standard lithography or electron beam etching processes, selective doping with nanoscale size area can also be achieved. This photoassisted doping method not only shows a facile route for MIT modulation via a doping route under ambient conditions but also supplies some clues for photosensitive detection in the future.

Miscanthus, a member of the Saccharinae subtribe that includes sorghum and sugarcane, has been widely studied as a feedstock for cellulosic biofuel production. Here, we report the sequencing and assembly of the Miscanthus floridulusgenome by the integration of PacBio sequencing and Hi-C mapping, resulting in a chromosome-scale, high-quality reference genome of the genus Miscanthus. Comparisons among Saccharinae genomes suggest that Sorghumsplit first from the common ancestor of Saccharumand Miscanthus, which subsequently diverged from each other, with two successive whole-genome duplication events occurring independently in the Saccharumgenus and one whole-genome duplication occurring in the Miscanthusgenus. Fusion of two chromosomes occurred during rediploidization in M. floridulusand no significant subgenome dominance was observed. A survey of cellulose synthases (CesA) in M. floridulusrevealed quite high expression of most CesAgenes in growing stems, which is in agreement with the high cellulose content of this species. Resequencing and comparisons of 75 Miscanthusaccessions suggest that M. lutarioripariusis genetically close to M. sacchariflorusand that M. floridulusis more distantly related to other species and is more genetically diverse. This study provides a valuable genomic resource for molecular breeding and improvement of Miscanthusand Saccharinae crops.

•A STSF configuration is proposed as the cathode flow field of AC-PEMFC.•A 3D multiphase model is applied and validated against the experiment.•The STSF improves the water content by reducing the internal temperature.•A superior output voltage and mass-specific power density are achieved.

The work presents the VUV-UV-vis photoluminescence of Ba3La(PO4)3:Ln3+ (Ln = Tb, Eu) prepared by a high-temperature solid-state reaction route. The excitation and emission spectra, the fluorescence decays and the time-resolved emission spectra were measured and discussed in detail. The results revealed that Tb3+ can efficiently transfer excitation energy to Eu3+ via its 5d and 4f states and therefore sensitizes Eu3+ emission under VUV-UV excitation, results in tunable emission in a large color gamut.

The efficient generation and active modulation of terahertz (THz) waves are strongly required for the development of various THz applications such as THz imaging/spectroscopy and THz communication. In addition, due to the increasing degree of integration for the THz optoelectronic devices, miniaturizing the complex THz system into a compact unit is also important and necessary. Today, integrating the THz source with the modulator to develop a powerful, easy-to-adjust, and scalable or on-chip THz emitter is still a challenge. As a new type of THz emitter, a spintronic THz emitter has attracted a great deal of attention due to its advantages of high efficiency, ultrawide band, low cost, and easy integration. In this study, we have proposed a multifield-modulated spintronic THz emitter based on the VO2/Ni/Pt multilayer film structure with a wide band region of 0–3 THz. Because of the pronounced phase transition of the integrated VO2layer, the fabricated THz emitter can be efficiently modulated via thermal or electric stimuli with a modulation depth of about one order of magnitude; the modulation depths under thermal stimulation and electrical stimulation were 91.8% and 97.3%, respectively. It is believed that this multifield modulated spintronic THz emitter will provide various possibilities for the integration of next-generation on-chip THz sources and THz modulators.

Purpose: The inverse planning simulated annealing (IPSA) algorithm has shown good results in cancer surgical treatment planning. However, an adaptive approach has not well been proposed for different shapes and sizes of tumors. The purpose of this study was to propose an adaptive, efficient and safe algorithm to get high-quality treatment dose planning, which is presented for pancreatic cancer. Methods: An algorithm employs an optimized IPSA and an adaptive process for adjusting the weight of organs at risk (OAR) and tumor. The algorithm, which was combined with ant colony optimization, was further optimized to reduce the number of needles. It could meet the clinical dose objectives within the tumors, reduce the dose distribution within the OAR and minimize the number of needles. Ten clinical cases were chosen randomly from patients, previously successfully treated in clinic to test our method. The algorithm was validated against clinical cases, using clinically relevant dose parameters. Results: The results were compared with clinical results in ten cases, indicating that the dose distribution within the tumor meets the clinical dose objectives. The dose received by OAR had been greatly reduced, and the number of needles could be reduced by about 50%. It was a significant improvement over the clinical treatment planning. Conclusions: In this paper, we have devised an algorithm to optimize the treatment planning in brachytherapy. The method in this paper could meet the clinical dose objectives and reduce the difficulty of operation. The results were clinically acceptable. This algorithm is also applicable to other cancers such as lung cancer.

The intercalation of transition metal atoms into the van der Waals gap of the layered transition metal dichalcogenides (TMDCs) results in modulations of electronic structures and transport properties of the host materials. In order to reveal the physical mechanism of intercalation, it is essential to elucidate the band structures, especially near the Fermi level, which contributes significantly to physical properties of a solid. Taking advantage of angle-resolved photoemission spectroscopy (ARPES), we studied how Cr intercalation modifies the electronic structures of the pristine ZrTe2in the intercalated compound Cr0.4ZrTe2. By comparing with the semimetal band structures of ZrTe2, we found a nonrigid shift in the band dispersions of Cr0.4ZrTe2, in which an indirect gap opens between the valence and conduction bands with only electron-type carriers contributing to the electronic states at the Fermi level. Moreover, additional electronic states emerge below the bottom of the conduction band at M and exhibit a strong temperature-dependent behavior. Our studies show that the intercalation of atoms in van der Waals crystals could regulate the inherent band dispersions of the host materials and induce new physical properties.

A rechargeable aqueous zinc-ion battery (ZIB) is one of the attractive candidates for large-scale energy storage. Its further application relies on the exploitation of a high-capacity cathode and the understanding of an intrinsic energy storage mechanism. Herein, we report a novel layered K2V3O8cathode material for the ZIB, adopting a strategy of charging first to extract part of K-ions from vanadate in initial few cycles, which creates more electrochemically active sites and lowers charge-transfer resistance of the ZIB system. As a result, a considerable specific capacity of 302.8 mA h g–1at 0.1 A g–1, as well as a remarkable cycling stability (92.3% capacity retention at 4 A g–1for 2000 cycles) and good rate capability, are achieved. Besides, the energy storage mechanism was studied by in situ X-ray diffraction, in situ Raman spectroscopy, X-ray photoelectron spectroscopy, and inductively coupled plasma mass spectroscopy. An irreversible K-ion deintercalation in the first charge process is proved. It is believed that this novel cathode material for the rechargeable aqueous ZIB and the optimizing strategy will shed light on developing next-generation large-scale energy storage devices.

Purpose: Pulmonary nodule detection has great significance for early treating lung cancer and increasing patient survival. This work presents a novel automated computer-aided detection scheme for pulmonary nodules based on deep convolutional neural networks (DCNNs). Methods: The proposed approach employs 3D DCNNs based on squeeze-and-excitation network and residual network (SE-ResNet) for pulmonary nodule candidate detection and false-positive reduction. Specifically, a 3D region proposal network with a U-Net-like structure is designed for detecting pulmonary nodule candidates. For the subsequent false-positive reduction, a 3D SE-ResNet-based classifier is presented to accurately discriminate the true nodules from candidates. The 3D SE-ResNet modules boost the representational power of the network by adaptively recalibrating channel-wise residual feature responses. Both models utilize 3D SE-ResNet modules to learn nodule features effectively and improve nodule detection performance. Results: On the public available lung nodule analysis 2016 dataset with 888 scans included, the proposed method reaches high detection sensitivities of 93.6% and 95.7% at one and four false positives per scan, respectively. Meanwhile, the competition performance metric score of 0.904 is achieved. The proposed method has the capability to detect multi-size nodules, especially the extremely small nodules. Conclusion: In this paper, a 3D DCNNs framework based on 3D SE-ResNet modules is proposed to detect pulmonary nodules in chest CT images accurately. Experimental results demonstrate superior effectiveness of the proposed approach in pulmonary nodule detection task.

Calcium-ion batteries (CIBs) by their strong competitiveness in cost and capacities have been considered as a desirable electrochemical energy technology. Nonetheless, the large ion radius and high charge density of Ca2+lead to sluggish electrochemical reaction kinetics and structural collapse of electrode materials. Herein, we construct a superlattice-like poly 3,4-ethylenedioxythiophene−V2O5(P–V2O5) heterostructure using an in situself-assembly strategy and employ it as a CIB cathode. In the heterostructure, the inserted poly 3,4-ethylenedioxythiophene enlarges the interlayer of V2O5, exposing abundant active sites for efficient Ca2+absorption and transport; meanwhile, it serves as an ‘interlayer linker’ between neighboring layers, which alleviates the volume change of V2O5during Ca2+insertion/extraction processes. Under the synergistic effect of these factors, the P–V2O5electrode exhibits a longer life span and greater rate capability than pristine V2O5. Specifically, the electrode delivers a significant capacity of 157.2 mAh/g at 1 A/g and excellent cycle stability over a long period of 7000 cycles at a high current density of 20 A/g. Furthermore, it has a superior rate capability of 129.0 mAh/g even at 30 A/g. Electrochemical mechanism studies reveal that the insertion/extraction of Ca2+in P–V2O5is highly reversible, accompanied by the interlayer contraction/expansion.

The strong interaction between Ti3C2Sxand FeN4species induces the central metal Fe(II) in FeN4species with intermediate spin state transferred to high spin state, in which the latter is favorable to initiate the reduction of oxygen.This strong interaction induces a remarkable Fe 3delectron delocalization with dband center upshift, boosting oxygen-containing groups adsorption on FeN4species and oxygen reduction reaction kinetics.The resulting FeN4–Ti3C2Sxwith FeN4moieties in high spin state exhibits high half-wave potential of 0.89 V vs. RHE and high limiting current density of 6.5 mA cm−2, enabling wearable zinc–air battery showing a good discharge performance with a maximum power density of 133.6 mW cm−2.