Initial Performance Research Articles

High initial conductivity and oxidation resistance of copper nanowire films via depositing oxalic acid.

Transparent conductive films based on copper nanowires (Cu NWs) have attracted extensive attention due to their cost-effectiveness. However, the inferior conductivity of Cu NWs compared to silver nanowires (Ag NWs) and the significant room temperature oxidation behavior have limited their widespread application and versatility. In this study, we present OA-Cu NW flexible transparent conductive films (FTCFs), which exhibit higher initial electrical performance and room temperature oxidation resistance. Initially, we synthesized high-purity Cu NWs and established a uniformly distributed Cu NW network on a PET substrate. Subsequently, post-treatment was carried out using a 0.1 M oxalic acid (OA) solution to immobilize oxalic acid on the Cu NWs. The resulting OA-Cu NW FTCFs show improved electrical properties compared to the original Cu NW FTCFs, with an optimal enhancement of 25%. The film demonstrated excellent room temperature oxidation resistance, showing minimal sheet resistance growth after 70 days of air exposure. Furthermore, the OA-Cu NW FTCFs exhibited good flexibility, as indicated by minimal changes in optoelectronic performance after a rigorous bend test of 10 000 cycles. The OA treatment not only effectively enhanced the performance of Cu NW FTCFs, but also circumvented high energy consumption and the selection of rare metal materials, thereby reducing the overall cost. As a result, the potential for large-scale production and application of Cu NW films is enhanced.

Beyond Binary Decisions: Evaluating the Effects of AI Error Type on Trust and Performance in AI-Assisted Tasks.

ObjectiveWe investigated how various error patterns from an AI aid in the nonbinary decision scenario influence human operators' trust in the AI system and their task performance.BackgroundExisting research on trust in automation/autonomy predominantly uses the signal detection theory (SDT) to model autonomy performance. The SDT classifies the world into binary states and hence oversimplifies the interaction observed in real-world scenarios. Allowing multi-class classification of the world reveals intriguing error patterns previously unexplored in prior literature.MethodThirty-five participants completed 60 trials of a simulated mental rotation task assisted by an AI with 70-80% reliability. Participants' trust in and dependence on the AI system and their performance were measured. By combining participants' initial performance and the AI aid's performance, five distinct patterns emerged. Mixed-effects models were built to examine the effects of different patterns on trust adjustment, performance, and reaction time.ResultsVarying error patterns from AI impacted performance, reaction times, and trust. Some AI errors provided false reassurance, misleading operators into believing their incorrect decisions were correct, worsening performance and trust. Paradoxically, some AI errors prompted safety checks and verifications, which, despite causing a moderate decrease in trust, ultimately enhanced overall performance.ConclusionThe findings demonstrate that the types of errors made by an AI system significantly affect human trust and performance, emphasizing the need to model the complicated human-AI interaction in real life.ApplicationThese insights can guide the development of AI systems that classify the state of the world into multiple classes, enabling the operators to make more informed and accurate decisions based on feedback.

Micelle‐Assisted Formation of Self‐Assembled Monolayers for Efficient and Stable Perovskite/Silicon Tandem Solar Cells

AbstractSelf‐assembled monolayers (SAMs) are widely utilized in high‐efficiency perovskite based solar cells due to their tunable energy alignment, minimal parasitic absorption, and compatibility with scalable processing. However, their performance on rough substrates and large‐area devices is often hampered by SAMs self‐clustering and poor perovskite wettability. In this study, these limitations are addressed with a straightforward micelle‐assisted SAMs adsorption strategy. By incorporating a small amount of long‐chain surfactants into the SAMs solution, the surfactants aggregate to form micelles that encapsulate SAMs molecules within their hydrophobic cores, significantly increasing the adsorption density of SAMs through micelle‐admicelle interactions. Notably, the residual surfactants further improve perovskite wettability, enhance crystal quality, and facilitate hole transport across the buried interface. Consequently, the wide‐bandgap single‐junction perovskite solar cell achieves a notable power conversion efficiency (PCE) of 20.95% and enhances long‐term stability compared to control devices. By integrating tunnel oxide passivated contact (TOPCon) silicon solar cells, a 1 cm2 monolithic perovskite/silicon tandem device achieving a PCE of 29.8% is demonstrated, ranking among the highest reported efficiencies for perovskite/homojunction silicon tandem solar cells. Furthermore, the unencapsulated device maintains 92% of its initial performance after 300 h of maximum power point (MPP) tracking under unfiltered Xenon Lamp illumination.

Hydrogel Soft Valve with Shape-Memory Actuators for Advanced Cuff Gripping and Fluid Control

Abstract Valves play a critical role in regulating flow, preventing backflow, and controlling pressure in hydro-pneumatic systems. However, most existing valves are based on rigid metallic components, which significantly restrict their applicability in biomedical fields and safe human-machine interactions. In this study, we introduce an innovative soft valve mechanism that integrates shape-memory alloy (SMA) wire with a circular hydrogel matrix, tailored for applications in cuff gripping and fluid flow control. Our hydrogel-encapsulated shape-memory annular (HESA) valve demonstrates the ability to transition between relaxed and contracted states within a rapid 8-second timeframe, exerting a force of approximately 15 mN and achieving up to 20% flow control efficiency. Although hydrogels can dehydrate and degrade over multiple actuation cycles, the HESA can be easily rehydrated to restore its initial performance and maintain significant stretchability. We demonstrate enhanced fluid control performance through the use of serially arranged HESA valves that offer a scalable solution for complex fluid management systems. In addition, we developed a real-time monitoring approach for hydrogel-based soft actuators using resistance changes (ΔR/R0) measured via an LCR meter, enabling precise performance tracking and timely rehydration to maintain functionality over extended actuation cycles. This innovative approach ensures sustained functionality and efficiency, underscoring the potential of the HESA valve for a variety of biomedical applications, including precise drug delivery systems, minimally invasive surgical tools, and advanced prosthetics.

Highly stretchable TPU/g-C3N4 composite nanofiber film for enhancing the piezo-photocatalytic sewage treatment by electrospinning-induced pretension

Enhancing the sustainability of catalysts is crucial for the practical application of piezo-photocatalytic degradation of sewage. This study introduces a novel approach by fabricating highly stretchable piezoelectric composite nanofiber films through electrospinning TPU/g-C3N4 mixture. The tight integration of TPU nanofibers with g-C3N4 few-layers pre-stresses g-C3N4 and strengthens the mechanical properties of the composite films, achieving a maximum tensile strain and stress of 862% and 6.90 MPa, respectively. With the assistance of 300 W ultrasound, the photocatalytic capability of the TPU/0.2g g-C3N4 composite nanofiber film is enhanced by 43% and maintains nearly 100% of its initial performance after 12 repeated experiments. The electronic, piezoelectric, and optical properties of uniaxial-strained monolayer g-C3N4 are studied by first-principles calculations, revealing that stretching in the armchair direction can double the in-plane piezoelectric coefficient, while compression in the armchair direction simultaneously alters the charge distribution within the heptazine rings and modulates the adsorption sites and energy for oxygen molecule. Therefore, ultrasound-induced dynamic strains can significantly enhance the photocatalytic effect. The degradation of electronic industrial wastewater demonstrates the practical application potential of the catalytic composite nanofiber film. This research offers a pioneering strategy for the development of efficient photocatalytic systems for sewage treatment.

MXene-Induced 2D Hard Carbon with In Situ Embedding of TiC Scaffolds Enabling Fast Na+ Diffusion and Interfacial Stabilization.

In situHard carbon (HC) is considered to be the most promising anode material for sodium-ion batteries (SIBs) due to the structural diversity, and low cost. However, limited Na+ transfer kinetics and structural defects lead to low initial Coulombic efficiency (ICE) and poor rate performance (typically <5 A g-1) of HC anodes. In this work, an interesting morphology-induced strategy is reported to synthesize 2D HC material. MXene is introduced into sugar-derived HC during hydrothermal process. After the subsequent carbonization, the as-obtained composite (TC5-1300) inherits the lamellar structure of MXene, and TiC nanoparticles by Ti3C2 MXene reacting with carbon are embedded into carbon layer. This concentrated architecture not only provides a robust scaffold for sodium storage, but also greatly reduces the defects of HC. Therefore, TC5-1300 maintains a high reversible capacity of 267.28mA h g-1 after 500 cycles at 2 A g-1 with a high ICE of 86.27%. Attributed to the excellent Na+ diffusion ability and interfacial stabilization, TC5-1300 exhibit a reversible capacity of 194mA h g-1 even at 8 A g-1. Furthermore, this morphology tailoring strategy can be generalized to other sugar sources derived carbon materials, which provides a valuable solution to commercial development of HC anodes.

Morphology Effect of FeWO4 Boosting Efficiency of Photocatalytic Uranium Extraction under Visible Light and Mechanism Investigation.

Wolframite (FeWO4) is a type of polyoxometalate known for its high chemical stability and electronic properties, which makes it an excellent photocatalyst. While FeWO4 has been widely utilized in the domain of organic catalysis, there are currently no documented reports regarding its use in the degradation of U(VI). In this study, the effect of changing the microscopic morphology of the FeWO4 catalyst to enhance its photocatalytic activity was explored. We effectively adjusted the microstructure and crystallinity of the FeWO4 catalyst by varying the hydrothermal synthesis temperature, subsequently analyzed in detail using synchrotron radiation and theoretical calculations. Additionally, the degradation rate of U(VI) in nuclear wastewater reached 98.8% using the FeWO4 catalyst samples synthesized at 200 °C, and the effect of coexisting ions on the performance of FeWO4 was studied, and the results showed that the degradation effect of certain amounts of Na+, Mg2+, K+, and Ca2+ on U(VI) was almost negligible, and it still maintained more than 90% of its initial performance after six cycles, which highlights the wide application prospects of the catalyst in the field of nuclear wastewater treatment in the future. Therefore, FeWO4 exhibits excellent photocatalytic uranium-extraction ability, anti-interference ability, stability, and a low-cost advantage. It holds great application prospects in the field of extracting radioactive uranium from nuclear wastewater.

Optimizing Zr Self-Compensation Doping Effect for High-Performance Wearable Amorphous Ga2O3 Photodetectors with Enhanced Durability in Harsh Environments.

Flexible photodetectors have garnered significant attention in recent years due to their vast potential. Among these, amorphous Ga2O3 (a-Ga2O3) stands out as a highly promising candidate for flexible solar-blind ultraviolet photodetectors, owing to its wide band gap, low-temperature fabrication advantages, and exceptional stability under extreme conditions. However, the fabrication of a-Ga2O3 inevitably introduces oxygen vacancy (VO) defects, leading to declined photodetection performance and compromised corrosion resistance. In this study, we developed a zirconium (Zr) self-compensation doping strategy with concentration optimization to suppress VO defects, thus enhancing the optoelectronic performance and durability of flexible a-Ga2O3 photodetectors. The introduction of Zr significantly eliminated intrinsic VO defects in Ga2O3 films, lowering the dark current by over 3 orders of magnitude from ∼10-8 to ∼10-11 A and reducing the response time by a factor of 50, achieving a response time of 6 μs. The detectivity of the optimized devices reached a high level of 3 × 1014 Jones, indicating exceptional sensitivity to ultraviolet light. Durability tests further demonstrated that the optimized devices exhibited outstanding mechanical robustness, maintaining over 95% of their initial performance after 10,000 bending cycles, and stable photodetection performance even under harsh salt spray conditions for 72 h. This work provides an effective solution for developing high-performance flexible photodetectors tailored for wearable devices and applications in harsh environments.

ChisNERE: a premodern Chinese corpus with named entity and relation annotation

Abstract This work contributes to the digital humanities approach for studying premodern Chinese history and culture by creating a large-scale dataset annotated with named entities and relations. Through careful annotation guidelines and labeling of over 200,000 characters, we developed a dataset containing 30,000 named entities across six types and 7,000 relations spanning twenty categories. Experiments on named entity recognition (NER) using pre-trained language models and large language models on this dataset achieved an initial performance of NER (91.32 percent F1). In addition, relationship extraction (RE) on the pretrained language model achieves an 85.32 percent F1 score. While there is still room for improvement, our annotated dataset and models provide a useful starting point for extracting semantic information from premodern Chinese texts. It represents an effort to connect history and technology, increasing accessibility and preservation of premodern Chinese cultural treasures. Furthermore, our dataset can facilitate downstream tasks like culture analysis, knowledge graph construction, and computational understanding of premodern Chinese. Overall, this research represents a significant step toward digitally exploring premodern Chinese documents, providing a pathway for future work on knowledge organization and computational analysis of this valuable cultural legacy. Our code and data are available at: https://github.com/tangxuemei1995/AnChineseNERE

Innovative bioinspired hydrogel scaffolds enabling in-situ hybrid nanoflower integration for dual-mode acetylcholinesterase inhibitor profiling.

Innovative bioinspired hydrogel scaffolds enabling in-situ hybrid nanoflower integration for dual-mode acetylcholinesterase inhibitor profiling.

Factors Associated with Low Back Overuse Injuries in Sports Science Students - A Prospective Study.

Sports science students (SPS) are more likely to be affected by low back pain (LBP) compared to the young, physically active population. The aim of this prospective study was to evaluate potential risk factors for LBP in the population of SPS. Before the beginning of the study the participants (n=54) performed initial physical performance testing and gave blood samples. Then they were followed up for 10 weeks. The observed outcome was LBP occurrence. The presence of the observed outcome was recorded using the Oslo Sports Trauma Research Centre Overuse Injury Questionnaire weekly. The association between LBP and potential explanatory factors - potential overtraining parameters (e.g. ferritin and iron levels, amount of sleep) and motor ability parameters (e.g. muscle strength, vertical jump) - was assessed using multiple binary logistic regression. During the 10 week prospective follow-up LBP was the most common problem affecting 13% of students. From the group of explanatory factors for LBP only two were included in the final model as statistically significant: low ferritin level (OR=8.70, p=0.008), and history of previous LBP (OR=8.69; p=0.006) made students more likely experience new LBP problems. The SPS that are more at risk of experiencing LBP are those with a history of LBP and those with low ferritin level. Awareness should be raised among students about the importance of comprehensive LBP prevention (preventive exercise, preventive medical check up including blood test).

2D/3D heterojunction carrier dynamics and interface evolution for efficient inverted perovskite solar cells

2D/3D heterojunction carrier dynamics and interface evolution for efficient inverted perovskite solar cells

High precision, high time-cadence measurements of the MgII index of solar activity by the GOES-R Extreme Ultraviolet Irradiance Sensor 2: EUVS-C initial flight performance

High precision, high time-cadence measurements of the MgII index of solar activity by the GOES-R Extreme Ultraviolet Irradiance Sensor 2: EUVS-C initial flight performance

Enhancing α-FAPbI3 Crystallization and Photovoltaic Performance through Inhibiting MFA Formation.

Methylammonium chloride (MACl) additive is almost irreplaceable in high-performance formamidinium (FA) perovskite photovoltaics. However, the byproduct of methyl formamidinium (MFA+) from the reaction of MA0 and FA damages the compositional purity and phase stability of α-FAPbI3. The addition of iodine (I2) to the FAPbI3 precursor has been reported to inhibit the formation of the byproduct MFA+. Here, we systematically investigate the effect of MAI on perovskite films and devices by using MAI to replace MACl and I2. The results demonstrate that the addition of MAI produces more I3- in the perovskite precursor, which inhibits the reaction between MA and FA and thus blocks the formation of MFA+. Meanwhile, MFA+ formation is reduced due to the delayed MACl evaporation caused by its strong interaction with I3-, facilitating the growth of α-FAPbI3 with an improved bottom morphology. It eliminates unreacted PbI2, forming a homogenized phase, and facilitates ordered growth along the (111) facet, enhancing charge transport and increasing the open-circuit voltage (VOC). The optimized device shows a 2% improvement in PCE, with the VOC increasing from 1.050 to 1.103 V. Additionally, the target device retains 97% of initial performance after 5495 min operation under maximum power point tracking, compared to 82.3% after 2000 min for the control device. This work provides insights into inhibiting the formation of MFA+ byproducts induced by the MA-FA side reaction following the introduction of MACl.

Exploiting Bis-Sulfonimide Featuring Multiple d-pπ Bonds to Construct Interlayers for Organic Solar Cells.

Herein, bis-sulfonimide (BSI), characterized by multiple d-pπ bonds rather than typical p-pπ bonds, is unprecedently utilized as a general and extendable building block to develop a series of multifunctional cathode interlayer materials (CIMs) for organic solar cells (OSCs). An illustrative CIM, BSIz-TT-PDI, demonstrates favorable alcohol processability, superior work function tunability, appropriate energy levels, strong self-doping effect, and decent crystallinity. These attributes contribute to its high conductivity exceeding 5×10-3 S/cm, as well as precise optimization of the interfacial connection between the active layer and metal cathode. Therefore, BSIz-TT-PDI-based OSCs delivers an outstanding efficiency of 18.08% using PM6:Y6 active layer while retaining 84% of its initial performance after tracking at the maximum power point under continuous illumination for 1100 hours. Additionally, the devices maintain over 94% of the optimal performance across a film thickness range of BSIz-TT-PDI from 5 to 90 nm. Moreover, BSIz-TT-PDI exhibits high compatibility with various active layers, enabling a record efficiency of 19.80% with the PM6:BTP-eC9:L8-BO active layer. This work not only introduces a new library of water/alcohol-soluble n-type semiconductors containing BSI, while also pioneers the creation of thickness-insensitive CIMs for stable and efficient OSCs by integrating electron-withdrawing components with d-pπ bonds.

Dipolar Carbazole Ammonium for Broadened Electric Field Distribution in High-Performance Perovskite Solar Cells.

Perovskite solar cells (PSCs) with ammonium passivation exhibit superior device performance and stability. Beyond typical chemical passivation, ammonium salts control the electronic structure of perovskite surfaces, yet the molecular structure-property relationship requires further understanding, especially the dipole effect. Here, we employed carbazole and its halogenated counterpart as the functional group of ammonium salts. 2-Chloro-carbazol-9-ethylammonium iodide (CzCl-EAI) with a rigid, conjugated molecular structure further provides chemical passivation and enhances the ambient stability of perovskites. In addition, we found that halogenation enhances the intramolecular charge transfer for a larger molecular dipole moment, leading to the depletion region of perovskite films threefold wider than that of the PDAI2 condition. The power conversion efficiency (PCE) of inverted PSCs based on mixed passivation reached 25.16% and certified 24.35% under the quasi-steady-state (QSS) measurement. Unencapsulated devices retained over 91% of initial PCE under ISOS-D-2 conditions over 1100 h and maintained 80% of their initial performance after 500 h of continuous light illumination in ambient air with a 50-60% relative humidity (RH).

Defects Mitigation and Charge Transport Promotion via a Multifunctional Lewis Base for Efficient 2D/3D Tin Perovskite Solar Cells

AbstractTin perovskite solar cells (PSCs) have garnered considerable attention as promising alternatives to lead PSCs due to their lower toxicity and outstanding optoelectronic properties. However, their efficiency and stability, particularly in 2D/3D tin PSCs, are usually hindered by high defect densities and inefficient carrier transport. In this study, a small‐molecule Lewis base with multiple functional groups‐cyanoacetohydrazide (CAH) is employed to mitigate defects and enhance charge transport in 2D/3D tin PSCs. It is revealed that the carbonyl, amine, and cyano groups in CAH form strong chemical bonds with Sn2+ ions, resulting in synergetic coordination effects. Moreover, the strong interaction between CAH and tin perovskite effectively regulates the crystallization process of perovskite film, resulting in a high‐quality tin perovskite film with enhanced crystallinity, reduced defect density, and a modulated 2D/3D phase distribution. As a result, the optimized 2D/3D tin PSCs achieve a remarkable power conversion efficiency of 15.06%, marking one of the highest values for 2D/3D tin PSCs. Furthermore, the optimized devices exhibit outstanding stability, retaining 95% of their initial performance after 2000 h of storage in a nitrogen atmosphere.

Mesostructured Pt alloy nanotubes with synergistic edge sites as bifunctional electrocatalysts for direct ethanol fuel cells

Direct ethanol fuel cells are considered indispensable and prospective energy storage devices due to their high volumetric energy density. Platinum (Pt) and Pt-based alloys are regarded as the most effective catalysts for both oxygen reduction reaction (ORR) and ethanol oxidation reaction. To further enhance the catalytic performance of the catalyst, it is necessary to improve the mass activity and utilization efficiency of Pt. In this work, we report a strategy for fabricating ordered mesostructured platinum-palladium alloy nanotubes (MPPNs) with high hierarchical porosity (68%) and abundant exposed active edge sites. MPPNs exhibit excellent catalytic activity and stability for ORR, with a mass activity approximately 7.4 times higher than that of the commercial Pt/C catalyst. After 20 k cycles of accelerated durability test for ORR, MPPNs demonstrate impressive retention of their original mass activity, maintaining a value of 93.9%. Furthermore, they display superior catalytic activity and stability for ethanol oxidation reactions, with a mass activity about 2.4 times higher than that of commercial Pt/C. After the 2,000 scan cycles, the mass activity remains at 84.5% of initial performance. Both experimental and theoretical studies reveal that the synergistic effect of neighboring (111) and (100) facets on the edge sites plays a critical role in enhancing the electrocatalytic selectivity, activity and stability.

Degradation of perovskite solar cells due to pinholes transforming into current leakage points

Abstract We have demonstrated the degradation of perovskite solar cells (PSCs) due to the transformation of pinholes into current leakage points. We intentionally formed pinholes in the perovskite (PVK) layer using laser processing techniques to evaluate the impact of the pinholes on the performances of the PSCs and to observe the behavior of the pinholes. The initial performance of the perovskite solar cell (PSC) with formed pinholes indicates that all formed pinholes did not work as current leakage points immediately after the fabrication. However, 2 weeks of storage in a dark desiccator at room temperature and 3 minutes of activation by the Air Mass 1.5 Global (AM 1.5G) irradiation caused some formed pinholes to transform into current leakage points. As a result of this transformation, the performance of the PSC with formed pinholes degraded. The transformation of pinholes into current leakage points was shown to be one of the degradation factors.

Dynamic Sodiation‐Driven Pore Reconstruction for Superior Initial‐Coulombic‐Efficiency and High‐Rate in Xylose‐Based Hard Carbon Anode

AbstractThe trade‐off between initial coulombic efficiency (ICE) and rate performance of hard carbon anodes remains a challenge in their practical applications, which is highly related to their complex active surface and porous properties. In this work, a high‐performance hard carbon anode is prepared using xylose as the carbon source with Co2+‐assisted catalysis, which exhibits an excellent initial coulombic efficiency of 91.6%, a high capacity of 396.4 mA h g−1, superior rate performance (176.3 mA h g−1 at 5 A g−1), and outstanding cycling stability. Cobalt‐ion treatment forms “expanded” graphite segments, facilitating the intercalation of desolvated sodium ions. Additionally, the intersection of these graphite segments creates “nanocaves”, enabling rapid sodium‐ion transport at the initial cycling stage. Using a combination of atomic‐resolution structural characterization and three‐dimensional electron tomography via transmission electron microscopy, it is observed that initially isolated nanoporous holes collapsed into interconnected pancake‐like pores during later cycling. The reconstructed narrow but connected pore structure provides abundant sodium storage sites and rapid charge transfer pathways, effectively accommodating structural stress during cycling. This work presents an innovative strategy for designing commercial hard carbon anode with advanced pore architectures and also provides new insight into the structural evolution of hard carbon during cycling.