The periodic herringbone reconstruction on the surface of Au(111) consists of alternating face-centered-cubic (fcc) and hexagonal-closed-packed (hcp) sites separated by dislocation lines and elbows. This well-known arrangement acts as an electronic superlattice for surface-state electrons, creating a mini-gapped band structure with a modulated electronic density. This rich and fascinating geometrical and electronic landscape has countless times served as a platform for molecular self-assembly and on-surface synthesis of carbon-based nanoarchitectures as well as a template for 2D material growth. In this work, we fabricated a long-range ordered organic quantum corral (QC) array the self-assembly of 1,3,5-benzenetribenzoic acid molecules onto the herringbone reconstructed Au(111) surface. The periodicity of this QC array is nearly half the one of the underlying Au herringbone reconstruction, enabling us to study the delicate interplay between the two potential landscapes by allowing the selective formation and electronic modulation of QCs both on hcp and fcc sites. Scanning tunneling microscopy/spectroscopy (STM/STS) can probe such local differences in the first partially confined state and finds that not only the energy onset of the surface state electrons is influenced but also the modulation of the shallow herringbone potential contributes to the newly formed band structure. This is confirmed by angle-resolved photoemission spectroscopy (ARPES), where the interplay of the periodic potentials introduced by the organic QC array and herringbone reconstruction results in the formation of a distinct surface state band structure. These results are corroborated and intuitively understood with electron-plane-wave expansion (EPWE) simulations. Our work shows that combined molecular and non-organic patterning can serve as a promising tool to macroscopically tune the electronic properties of metal surfaces in a controllable manner.

Expression of concern for 'A hysteresis-free perovskite transistor with exceptional stability through molecular cross-linking and amine-based surface passivation' by Hyeong Pil Kim , , 2020, , 7641-7650, https://doi.org/10.1039/C9NR10745B.

This study demonstrates the use of a top-gate ferroelectric field effect transistor (FeFET) with the replacement electrode solid phase epitaxy (SPE) method and high deposition temperature during atomic layer deposition (ALD). By employing these engineering techniques, the average grain size was successfully reduced, and the formation of the non-ferroelectric monoclinic phase (m-phase) was effectively inhibited. In terms of ferroelectric properties, both the remanent polarization (2) and coercive field () values demonstrated significant increases by 35% and 50%, respectively. Notably, improvements were observed in memory characteristics, with the memory window (MW) increasing from 0.3 V to 0.9 V and endurance enhancing by three orders of magnitude. In terms of synaptic properties, there was an enhancement in the number of conductance states from 100 to 136, an increase in the / ratio from 5.16 to 90, and an improvement in weight update linearity. The simulation results based on the MNIST dataset show an improvement in inference accuracy from 65% to 85%.

Flexible fibrous electrodes have emerged as a promising technology for implantable biosensing applications, offering significant advancements in the monitoring and manipulation of biological signals. This review systematically explores the key aspects of flexible fibrous electrodes, including the materials, structural designs, and fabrication methods. A detailed discussion of electrode performance metrics is provided, covering factors such as conductivity, stretchability, axial channel count, and implantation duration. The diverse applications of these electrodes in electrophysiological signal monitoring, electrochemical sensing, tissue strain monitoring, and electrical stimulation are reviewed, highlighting their potential in biomedical settings. Finally, the review discusses the eight major challenges currently faced by implantable fibrous electrodes and explores future development directions, providing critical technical analysis and potential solutions for the advancement of next-generation flexible implantable fiber-based biosensors.

The escalation of global energy crises and environmental degradation has intensified the focus on photocatalytic technology, which harnesses solar energy for direct chemical reactions in a green manner. Metal clusters serve as multifunctional components in photocatalytic systems, with their unique properties (such as dimensions, composition, and surface modification) offering a plethora of regulatory mechanisms for designing innovative and efficient cluster-based photocatalysts. These improvements enhance light absorption, charge separation, and catalytic activity. This comprehensive review explores the fundamental principles and applications of photocatalytic technology, emphasizing the role of metal cluster materials in advancing this field. The synthetic methodologies, especially AI-assisted synthesis, characterization techniques, and modification strategies of metal cluster materials are introduced in detail, highlighting their significance in enhancing photocatalytic performance. The applications of metal clusters in various photocatalytic processes are also discussed, including water splitting, CO reduction, N fixation, pollutant degradation, HO generation and selective organic synthesis, showcasing their potential in environmental remediation and energy transformation. Finally, the review concludes with an outlook on future research directions, emphasizing the need for innovating synthesis methods, developing advanced characterizations techniques, and optimizing catalytic performance to address existing challenges and unlock the full potential of cluster-based photocatalysts.

Ultrafine ordered intermetallic nanoparticles are emerging as promising electrocatalysts for the oxygen reduction reaction (ORR) in fuel cells. However, they are difficult to obtain because high-temperature annealing inevitably leads to metal sintering, resulting in larger crystallites. Additionally, the resulting electronic effects are difficult to control, limiting both performance and stability improvements. Herein, we present an ultrafine ordered intermetallic platinum-cobalt alloy encaged in nitrogen-doped carbon (PtCo/NC) with a small particle size of 4.18 ± 1.00 nm and a high electrochemically active surface area (ECSA) of 73.16 m g. The contraction of the Pt-Pt pair induces strong electron coupling, resulting in electron transfer from Co to Pt. Using spectroscopies, we revealed that incorporating the cost-effective transition metal Co into the Pt lattice induces Pt-Pt contraction and generates additional Pt d-band occupancy, which accelerates the protonation of *O to *OH, thereby significantly enhancing the kinetics of the four-electron ORR process. The meticulously designed catalyst achieves a superior half-wave potential of 0.89 V RHE and a remarkable mass activity of 0.79 A mg. More importantly, after 10 000 cycles, the particle size expansion is marginal (5.01 ± 0.92 nm), alongside slight reductions in mass activity (6%) and specific activity (2%), demonstrating excellent catalytic stability in an acidic medium.

Inflammatory bowel disease (IBD) affects approximately 3.1 million individuals in the U.S., causing deleterious symptoms such as bloody diarrhea and leading to an increased risk of colorectal cancer. Effective imaging is crucial for diagnosing and managing IBD, as it allows for accurate assessment of disease severity, guides treatment decisions, and monitors therapeutic responses. Computed tomography (CT) with contrast agents is the gold standard for imaging the gastrointestinal tract (GIT). However, current agents are less effective in obese patients and lack specificity for inflamed regions associated with IBD. Moreover, IBD treatments often have limited efficacy and do not address the role of oxidative stress in IBD progression. This study explores dextran-coated cerium oxide nanoparticles (Dex-CeNP) as a CT contrast agent and therapeutic for IBD, leveraging cerium's superior K-edge energy profile, dextran's inflammation-specific targeting, and cerium oxide's antioxidant properties. Herein, we synthesized Dex-CeNP formulations using 5, 10, 25, and 40 kDa dextran to explore the effect of dextran coating molecular weight. assays showed formulation biocompatibility and demonstrated that 5 kDa Dex-CeNP had the highest catalytic activity, which translated into improved suppression of inflammation. As a result, this formulation was selected for use. CT imaging of mice subjected to dextran sodium sulfate (DSS) colitis showed that Dex-CeNP provided better contrast in the GIT of mice with colitis compared to iopamidol (ISO), with pronounced attenuation in the large intestine and disease- specific retention at 24 h. Additionally, Dex-CeNP significantly decreased Disease Activity Index (DAI) scores, and diminished gastrointestinal bleeding when compared with a currently approved drug, indicating that it is an effective treatment for colitis. Studies also revealed that the Dex-CeNPs were safe and well-excreted following administration. In summary, Dex-CeNP has significant promise as a dual-purpose agent for CT imaging and treatment of IBD.

Gentle annealing and photopolymerization under inert atmospheres strongly enhance the quality of polydiacetylene monolayers. These simple measures not only triple the average degree of polymerization but also alter the preferred photoexcitation mode and cause pronounced nano-alignment during the early stages of polymerization.

Metal halide perovskite semiconductors (MHSs) are emerging as potential candidates for opto-spintronic applications due to their strong spin-orbit coupling, favorable light emission characteristics and highly tunable structural symmetry. Compared to the significant advancements in the optoelectronic applications of MHSs, the exploration and control of spin-related phenomena remain in their early stages. In this minireview, we provide an overview of the various spin effects observed both in achiral and chiral MHSs, emphasizing their potential for controlling interconversion between spin, charge and light. We specifically highlight the spin selective properties of chiral MHSs through the chirality-induced spin selectivity (CISS) phenomena, which enable innovative functionalities in devices such as spin-valves, spin-polarized light-emitting diodes, and polarized photodetectors. Furthermore, we discuss the prospects of MHSs as spintronic semiconductors and their future development in terms of material design, device architecture and stability.

Structural instability in electrode materials is a critical barrier to the practical application of potassium-ion batteries (PIBs) in terms of long-term durability. To overcome this, we integrated amorphous FeP within continuous three-dimensional (3D) carbon fiber networks, fabricated through an electrospinning process. The amorphous structure of FeP facilitates isotropic volume expansion, effectively distributing stress uniformly across the electrode and mitigating degradation during cycling. Additionally, the loosely packed atomic arrangement and interconnected 3D conductive framework enable smoother potassium-ion diffusion, thereby enhancing the kinetic performance. Therefore, the well-designed amorphous FeP/porous carbon nanofibers (A-FeP@PCNFs) exhibit a remarkable specific capacity of 358.3 mA h g at 0.1 A g and demonstrate exceptional cycling durability, retaining a reversible capacity of 152.0 mA h g after 2400 cycles at 3 A g. This innovative design offers a robust approach for developing excellent electrochemical performance anode materials with superior structural stability and rapid electrochemical response, advancing the potential of PIBs in energy storage applications.

The optoelectronic properties of AgS nanocrystals with different surface passivation treatments have been investigated using femtosecond transient absorption spectroscopy. Plain AgS nanocrystals and improved surface-passivated nanostructures were studied under different pump fluences and photon energies. Surface passivation significantly sharpens excitonic resonances, reducing defect-assisted recombination. Transient absorption spectroscopy reveals that the excited state dynamics are dominated by trapping and exciton recombination at low exciton densities, while fluence dependence studies reveal significant contributions from biexcitons and Auger recombination in all samples at high exciton densities. Notably, surface-passivated nanostructures exhibit faster multi-exciton recombination dynamics, highlighting the impact of effective surface passivation.

Cancer is one of the leading causes of death worldwide and represents a significant burden on global health systems. Many existing chemotherapy treatments come with severe side effects, ranging from hair loss to cardiotoxicity, and many types of cancer express chemotherapy resistance, such as triple-negative breast cancer. This study presents a novel boron/nitrogen-doped carbon nano-onion (BN-CNO) based nanocarrier system that can deliver doxorubicin (DOX) to cancer cells a pH-dependent drug release mechanism. The nanocarrier formulation consists of a hyaluronic acid/phospholipid conjugate (HA-DMPE) that is non-covalently bound to the BN-CNOs upon which DOX is loaded π-π stacking interactions. The HA-DMPE/BN-CNO/DOX system enhances the uptake and anticancer effects of DOX in MDA-MB-468 and MDA-MB-231 TNBC cells whilst reducing the cardiotoxicity of DOX in AC-16 human cardiomyocytes.

Per- and polyfluoroalkyl substances (PFAS) are a class of chemicals known for their persistence in the environment due to their amphiphilic nature and the strength of carbon-fluorine bonds. While these properties lead to various industrial and commercial applications including firefighting foams and non-stick coatings, these same characteristics also result in significant environmental and health concerns. This study employs atomistic molecular dynamics (MD) simulations to achieve molecular level insights into PFAS self-assembly and adsorption dynamics, to inform PFAS water remediation. MD simulations of PFAS with different headgroup chemistries and chain lengths on a graphene sorbent surface under varied pH conditions were performed. These simulation results elucidated the impacts of headgroup, chain length, and pH on PFAS adsorption behavior. At neutral pH, PFAS headgroups are fully deprotonated, causing electrostatic repulsions that lead to micelle-like aggregate formation in solution, hindering adsorption. Conversely, at acidic pH, these repulsions are diminished due to protonated headgroups, resulting in higher adsorption percentage with large, stacked aggregates that fully adsorb onto the sorbent. Additionally, chain length notably influenced aggregation, with longer chains forming larger aggregates and achieving more stable adsorption compared to shorter chains. Furthermore, perfluoro-sulfonic acids (PFSAs) displayed stronger adsorption and greater aggregate order than perfluoro-carboxylic acids (PFCAs) in general. These findings underscore the complex interplay between PFAS structure and the dynamics of their adsorption behaviors, as well as the potential of pH as a tuning parameter to enhance PFAS adsorption stability and thereby improve PFAS removal efficiency.

Ceria (CeO)-based gold (Au) catalysts exhibit remarkable catalytic performance for preferential oxidation of CO in an H-rich stream (CO-PROX), and their activity can be further enhanced by defect engineering and regulation of Au sites. Herein, oxygen vacancies (O) were constructed on CeO using different reducing agents, including H, NaBH and ascorbic acid, to modulate the electronic structure and coordination environment of Au sites. The properties of O and Au species were investigated by a series of characterization methods, such as electron paramagnetic resonance (EPR), electrochemical impedance spectroscopy (EIS), and X-ray photoelectron spectroscopy (XPS). The results of catalytic tests for CO-PROX showed that the sample reduced by H at 400 °C (Au/CeO-H-400) achieved the best performance, which completely converted CO across a wide temperature window, ranging from 70 °C to 150 °C, while maintaining satisfactory selectivity and stability. The superior performance was attributed to the fact that, unlike ascorbic acid and NaBH, H is a small molecule with negligible steric hindrance, leading to a more concentrated distribution of O. These vacancies promoted the formation of partially oxidized Au with a moderate Au-O coordination number, which enhanced CO adsorption and facilitated the activation of lattice oxygen, thereby contributing to the exceptional catalytic activity.

Metal-organic framework (MOF)-derived carbons, known for their highly tunable structures, have attracted considerable attention for electrochemical applications. Efficient ion and electron transport, along with low electrode resistance, is critical for enhancing performance in these areas. To optimize MOF-derived carbons, we synthesize Zn-based zeolitic imidazolate framework (ZIF-8) nanocrystals with controlled sizes and a narrow size distribution, resulting in nanoporous polyhedral carbon structures. The sample is then subjected to carbonization to yield ZIF-8-derived carbon (ZIF-8-C) doped with heteroatoms, and subsequently, performance evaluations of supercapacitors are conducted to assess their ion and electron transport properties. Larger particles exhibit greater capacitance loss at high scan rates or current densities, likely due to underutilization of pores for ion diffusion. Uniform particle sizes facilitate ordered packing, improving electron pathways compared to electrodes with non-uniform particles and yielding higher electrochemical performance despite similar specific surface areas. Notably, the electrode prepared with the smallest and most uniformly sized ZIF-8-C-m1 exhibits a specific capacitance of 206.4 F g at 1 A g, along with excellent rate capability and stability, retaining 99.7% of its capacitance after 10 000 cycles at 10 A g. In a two-electrode system, it achieves an energy density of up to 19.4 W h kg at a specific power of 350 W kg. The results present here offer valuable insights into the utilization of nanoporous carbons across diverse electrochemical applications.

The incorporation of high salt concentrations in ionic liquid (IL) electrolytes, forming superconcentrated ionic liquids, has been shown to improve Li-ion transference numbers and enhance cycling stability against lithium metal anodes. However, this benefit comes at the cost of significantly increased viscosity and reduced ionic conductivity due to the formation of large ion aggregates. To optimize conductivity further, a co-solvent can be introduced at an optimal concentration to enhance ion transport while preserving superior interfacial stability. The effectiveness of this approach depends on the solvent as it affects ion diffusion to varying degrees. This computational study examines how co-solvents can effectively enhance metal ion diffusion in superconcentrated ionic liquids by comparing two widely used organic solvents. We found that the key lies in their ability to effectively participate in Li solvation shells, disrupting the large Li-anion aggregates. Our results show that anion exchange in a Li(anion)(solvent) hybrid solvation shell occurs more rapidly than in a Li (anion) solvation shell, facilitating Li diffusion through a structural diffusion mechanism. A co-solvent with a high donor number exhibits a stronger affinity for lithium ions, which is identified as a crucial factor in enhancing ion diffusion. This work provides valuable insights to guide the design of superconcentrated ionic liquid electrolytes for lithium-metal battery development.

In recent years, the flexibility of porous organic polymers has demonstrated very unique properties during their applications. This paper reports a novel soluble porous polymer (named BIT-POP-75 and BIT-POP-75-OH) with 1,2-diketone and 1,2-diol subunits in the flexible polymer chain using contorted subunits. The solubility of the porous polymer and the flexible chelating 1,2-diol moiety facilitates the high loading and uniform dispersion of Pd nanoparticles to give the catalyst Pd@BIT-POP-75-OH, which shows high efficiency ( = 0.965 min) for the catalytic reduction of 4-nitrophenol with good recyclability (10 cycles).

Cholesterol and glucose are two important biomarkers that are linked to different human diseases. In this work, we have designed a turn-on fluorescent biosensor based on carbon dots hybridized by AgNPs (CD@AgNPs). Vent. extract was used as a rich carbon source for the green synthesis of carbon dots, which exhibited excitation-dependent fluorescence with maximum emission at 409 nm under 350 nm excitation. In this approach, hydrogen peroxide, a by-product of enzymatic reactions between oxidase enzymes and analytes, etches AgNPs, leading to fluorescence recovery. The designed biosensor showed a great linear range (2-60 μM for cholesterol and 4-250 μM for glucose) with very low limits of detection (3 μM for cholesterol and 38 μM for glucose), which are lower than the concentrations of these biomarkers in human body fluids. The great selectivity and sensitivity of the designed biosensor enable it to be used for the detection of biomarkers in complex media such as artificial human plasma in only 30 min. This work could open new avenues for researchers in the fields of sustainability and biomedicine, where green and accurate biosensors are required.

Metallized biaxially oriented polypropylene (BOPP) films are widely used in electronics and electrical power systems. However, as the demand for metallized films (MFs) with enhanced properties increases across various applications, studying the micro-level electron transfer mechanisms has become a promising approach to regulate the electrical characteristics of the metallized films. In this work, we systematically investigated the surface electron transfer mechanism, space charge distribution injected from external electrodes at the nanoscale, and macro-level electrical characteristics in different MFs. Results revealed that the MFs with thinner metallized layers exhibited greater surface charge accumulation, slower dissipation and reduced charge injection into the dielectric layer, thereby affecting the dielectric constant, leakage current, breakdown property and self-healing characteristics of the samples. We employed tunnelling current measurements using atomic force microscopy (AFM) to calculate the energy barrier height in different metallized films for studying the influence mechanism of the metallized layer thickness and the introduction of BaTiO. These results established a relationship between electron transfer at the nanoscale and macro-level material electrical properties of different BOPP metallized films. Additionally, the results of space charge testing indicated that the accumulation amount of space charge determined the energy storage capacity of the MFs, and at the same time, a bipolar carrier simulation model was developed to validate the electron transfer mechanism. The simulation results aligned well with the experimental findings, further confirming the influence of the BaTiO composite layer on nanoscale charge transfer dynamics.

During the hydrogen evolution reaction, H gas bubbles form on the electrode surface, significantly affecting electrochemical processes, particularly at high current densities. While promoting bubble detachment has been shown to enhance the current density, the mechanisms governing gas bubble detachment at the electrochemical interface remain poorly understood. In this study, we investigated the interplay between electrode surface morphology and electrolyte composition on single H gas bubble detachment during hydrogen evolution reaction (HER). Using well-defined Pt microelectrodes as model systems, we systematically modify and enhance their surface roughness through mechanical polishing to investigate these effects in detail. By modulating the Marangoni effect through variations in electrolyte composition and applied potential, we identified two distinct detachment behaviours. When the Marangoni force acts towards the electrodes, H gas bubbles are positioned closer to the electrode surface and exhibit roughness-dependent detachment, with smaller bubbles detaching earlier on rougher surfaces. Conversely, when the Marangoni force is directed away from the electrode, H gas bubbles are located farther from the electrode surface and show roughness-independent detachment sizes. These findings highlight the importance of considering both electrode and electrolyte effects to optimize gas bubble detachment during electrochemical reactions.

Ferritin cages are an effective platform to encapsulate and stabilize a range of active cargoes and present a promising stepping stone towards a wide range of applications. They have been explored for optoelectronic applications in combination with fluorescent proteins towards bio-hybrid light-emitting diodes (Bio-HLEDs) only recently. However, protein integration within the cage or coassembled ferritin cages relies on electrostatic interactions and requires the supercharging of the fluorescent protein that easily compromises functionality and stability. To address this limitation, we have developed a fusion protein combining the apoferritin (TmaFt) with a green fluorescent protein named mGreenlantern (mGL). This approach avoids jeopardizing both the cage assembly capability of TmaFt and the photophysical features of mGL. After optimizing the fusion protein mGL-TmaFt with respect to the linker length, assembling efficiency, and mGL payload into the cage (mGL@TmaFt), our findings reveal that they exhibited enhanced thermal and structural stabilities in both solution and when embedded into a polymer matrix. This enables effective mGL shielding, reducing H-transfer deactivation of the chromophore and water-assisted heat transfer across the polymer network. Indeed, the photo-induced heat generation in Bio-HLEDs operating at high currents was significantly reduced, resulting in a 30- and 15-fold higher device stability compared to references with either mGL or mGL-TmaFt proteins, respectively. Overall, this work sets in the potential of protein cage design for photon manipulation in protein lighting devices.