Dirac cones and topological torsional modes in phononic nanowires using Su-Schrieffer-Heeger Model.

Colloidal particle shape matters: Emulsion-directed shape design, interfacial mechanisms, and applications.

This work presents a simple and low-cost approach to triboelectric sensing based on commercially available nonwoven polypropylene (PP) membranes paired with electrospun polyvinylidene fluoride (PVDF) to form a triboelectric nanogenerator (TENG), which is further utilized as a sensor operating predominantly in a non-contact regime. The initial contact electrification creates an interfacial charge state that is retained after contact, allowing subsequent separation changes to generate electrical signals via electrostatic induction without requiring continuous contact. The introduction low-permittivity sublayers (polyvinyl chloride (PVC), biaxially oriented polyethylene terephthalate (BOPET), and low-density polyethylene (LDPE)) beneath the tribonegative PVDF membrane significantly enhances the TENG's mechano-electric performance by modifying the electric field distribution in the multilayer dielectric structure. The PP/PVDF+LDPE layer achieves a peak open-circuit voltage of 689V and a maximum power density of 5.46 mWcm⁻² in comparison to 376V and 2.05 mWcm⁻², respectively, for PP/PVDF. This confirms that the dielectric permittivity of the supporting layer is a key parameter controlling the electrical output of the PP/PVDF triboelectric system. The device was validated under various pressure stimuli and vibrations demonstrating its ability to simultaneously sense motion and harvest energy.

Topological logic gates based on valley-locked interface states of acoustic and electromagnetic waves in two-dimensional phoxonic crystals

We report a materials-engineering strategy to enhance triboelectric nanogenerator (TENG) output by embedding a ternary g-C₃N₄/TiO₂@polyaniline (GTP) nanocomposite into PVDF tribopositive electrodes and pairing them with PTFE tribonegative layers of systematically varied composition from 30 to 60 wt%). XPS, TEM, FESEM/EDX, UV-Vis, and DSC confirm that TiO₂ nanoparticles are well distributed on g-C₃N₄ nanosheets and interconnected through a conducting PANI network, with evidence of interfacial Ti-O-C/Ti-N bonding, Ti3⁺ associated defect states, and band-tail absorption (Urbach energy, EU = 0.31 eV), indicating localized electronic states that support charge storage/transfer." In vertical contact-separation mode, the devices exhibit a composition-dependent trade-off: the 30 wt% PTFE configuration delivers the highest short-circuit current (Isc = 2.86 μA) and peak power (Pmax = 10.3 μW), whereas the 60 wt% PTFE device yields the maximum open-circuit voltage (Voc = 4.56 V). These results demonstrate that voltage-current characteristics can be tuned through interfacial state engineering and controlled adjustment of the tribonegative layer composition. To confirm repeatability and stability under manual tapping, the best-performing 30 wt% and 60 wt% devices has been validated using an automated cycle-resolved statistical analysis.

Biocorrosion behavior of high-purity Mg and Mg-Zn-Zr-Nd alloy during exposure to Porphyromonas gingivalis.

Decoupling droplet transport from the nucleation interface via wire-guided sliding condensation.

Bulk heterojunction (BHJ) organic solar cells (OSCs) have achieved high efficiencies but suffer from poor morphological stability due to phase separation after long-term operation. Single-component OSCs (SCOSCs) based on double-cable polymers (DCP), offer improved stability through covalently linked donor and acceptor units. However, their efficiency remains limited by inefficient charge generation arising from extensive intermixed morphologies. Here, we report a fluorinated double-cable polymer, DCPY2-F, which achieves an outstanding efficiency of 14.8% with high short-circuit current density of 26.83 mA cm-2. Ultrafast pump-probe transient absorption spectroscopy reveals that fluorination of DCPY2 into DCPY2-F accelerates interfacial charge transfer and long-range charge separation dynamics. The pump-push-probe transient absorption spectroscopy and steady-state electroluminescence show that the faster interfacial charge transfer arises from a reduced reorganization energy and a correspondingly accelerated molecular reorganization process (2.5 ps vs. 0.8 ps). Despite comparable acceptor aggregate sizes with DCPY2, DCPY2-F also shows faster long-range charge separation dynamics, which we attribute to a narrower charge transfer states (CTs) energetic distribution. Molecular dynamics simulations further reveal that fluorination strengthens non-covalent interactions, promoting well-aligned intermolecular donor-acceptor interfaces. These structurally and energetically ordered interfacial CT states enable ultrafast and efficient charge generation. In corresponding binary blends, fluorination similarly enhances charge-transfer dynamics and photocurrent. These findings establish a unified fluorination strategy for accelerating charge generation dynamics in both SCOSCs and blends, and provide a mechanistic understanding for improving charge generation for high-performance single-component systems.

Silicon-based optoelectronic devices represent a cornerstone of modern optoelectronics, owing to their low cost and mature fabrication infrastructure. Their performance optimization hinges critically on precise control of the Schottky barrier height (SBH). As a nondestructive, continuously tunable physical parameter, pressure offers a novel strategy for dynamic SBH modulation. Here, we employed high-pressure techniques to investigate Pt/Si Schottky junctions. With increasing pressure, the SBH decreased monotonically from 0.713 to 0.446 eV at a rate of -165.8 meV/GPa and was completely eliminated above 4.3 GPa, indicating a pressure-driven Schottky-to-Ohmic transition. Mechanistic analysis revealed that pressure modulates SBH primarily by regulating interfacial gap state density and reconstructing the band structure. This transition led to a drastically enhanced photoresponse, with photocurrent intensities increasing by 100-fold and 3400-fold under 532 and 660 nm laser excitation, respectively. This work elucidates the pressure-tuning behavior of silicon-based Schottky junctions and their regulatory mechanism on photoelectric performance, providing a new strategy for the design of high-performance silicon optoelectronic devices.

Understanding how curved molecular carbon interfaces regulate sulfur redox remains a central challenge for the rational design of advanced Li-S and Na-S batteries. Here, we present a systematic theoretical study of sulfur species adsorbed on C60 and establish a mechanistic framework for curvature-gated sulfur redox. The calculated adsorption energies reveal pronounced chain-length-dependent stabilization on C60, with terminal short-chain sulfides being most strongly bound, including C60-Li2S and C60-Na2S. Gibbs free-energy analysis further shows that both Li-S and Na-S pathways share a common thermodynamic bottleneck at the M2S4 → M2S2 conversion step, with uphill free-energy changes of +0.76 eV and +0.83 eV, respectively. Electronic-structure analyses demonstrate that this selective stabilization is governed by interfacial polarization rather than geometric confinement alone and evolves from weak contact for neutral sulfur to predominantly electrostatic interaction for intermediate-chain sulfides and a hybrid covalent-electrostatic mode for terminal sulfides. At the orbital level, both C60-Li2S and C60-Na2S exhibit a common motif consisting of a fullerene-centered low-lying acceptor manifold and mixed occupied interfacial frontier states. Most importantly, although Na2S binds more strongly to C60 than Li2S, its final Na-S bond-cleavage barrier (1.05 eV) is markedly lower than the corresponding Li-S bond-cleavage barrier (1.48 eV), showing that Na2S is kinetically more labile than Li2S on the same curved carbon interface. These results identify C60 as a curvature-gated reaction interface that reshapes sulfur redox through stage-selective thermodynamic bias, polarization-governed stabilization, and metal-dependent terminal conversion kinetics.

Inverted CsPbI3 perovskite solar cells (PSCs) have attracted more attention in single-junction and tandem solar cells, owing to the optimal band-gap, superior photothermal stability, and device architecture compatible with commercial bottom cells such as CuInSe2 and silicon. However, their development is hindered by challenges including the complex phase transition process, interfacial energy-level mismatch, unpassivated defects, and the suboptimal transport layer. A comprehensive understanding of the material characteristics, phase transition mechanisms, and interface state of CsPbI3 is therefore essential to address these issues. In this review, we systematically examine the phase-transition dynamics of CsPbI3 and summarize recent advances in fabricating efficient and stable inverted CsPbI3 PSCs, focusing on: (1) Regulation of the phase transition and bulk crystallization; (2) Management of interface energy-level and defect passivation; (3) Selection of hole transport materials and their integration in tandem solar cells. Finally, we outlinethe remaining challenges and future perspectives to guide the development of high-performance and operationally stable inverted inorganic perovskite-based single-junction and tandem photovoltaics.

In this work, we investigate the origin of the dynamic on-resistance (RDSON) instability in GaN hybrid drain-embedded gate injection transistors under hard-switching conditions. Double-pulse tests reveal that the gate transient pulse voltage not only increases with increasing the turn-on time but also shows a non-monotonic dependence on drain voltage. Correspondingly, the dynamic RDSON initially increases, reaching a maximum at ∼200 V, then decreases at higher drain voltages. Based on in situ drain voltage transient measurements, three traps (DP1–DP3) were identified by extracting the time constant spectroscopy. DP1 is located in the bulk GaN or AlGaN buffer layer and shows negligible influence on dynamic RDSON. While DP2 and DP3 are related to interface states at the AlGaN/GaN heterojunction, which is further confirmed by deep-level transient spectroscopy with a high interface state density on the order of ∼1011 cm−2 eV−1. The results further confirm that the dynamic RDSON instability is attributed to the competition between electron trapping at these interface states and drain-initiated hole injection. These findings provide new insights into the trap-mediated dynamic performance of GaN-based high-electron-mobility transistors.

With the increased aircraft volume and lifetime cost, the performance of the honeycomb sandwich structure needs to be further improved. This paper innovatively proposes a method for adjusting the strength of multi-layer honeycomb sandwich structures within a limited space. Based on the existing technology, structural innovations have been made, expanding the application of honeycomb structures. Through 3D printing technology, the material composition and mechanical properties of the middle panel can be precisely controlled, enabling flexible design of the performance of honeycomb sandwich structures. Compared with traditional manufacturing methods, it has significant advantages. Compression experiments were carried out on different samples by a universal testing machine. The influence of the strength of the middle panel on the compression performance, energy absorption performance, and transverse dimension of the honeycomb sandwich structure was analyzed and verified by theory. The morphology of the honeycomb core, panel, and interface state after compression was observed by an electron microscope. The failure mechanism was analyzed, and the accurate platform endpoint was obtained by solving the image slope. The results show that with the increase of the strength of the middle panel, the compression performance and energy absorption capacity of the honeycomb sandwich structure decreases gradually in the yield stage. In contrast, the compression performance increases gradually in the rapid climbing stage, and the transverse size decreases gradually. By changing the strength of the middle panel, the average compressive stress in the yield stage can be increased by 7.69%, the energy absorption capacity can be increased by 18.11%, the compressive stress can be increased by 23.12%, and the transverse dimension can be decreased by 3.66% when the strain is 0.545. The above research provides a theoretical basis for improving the compression performance and energy absorption capacity of honeycomb multi-layer structures.

This Letter introduces a novel Nb/Au metallic system toward the realization of high-performance Schottky contacts on p-type GaN:Mg. In particular, the influence of depositing a thin niobium layer on the p-GaN surface was investigated toward the realization of low reverse leakage current, a close-to-ideal ideality factor (n), a high ON/OFF ratio, and a minimal interface state density (Dit). The fabricated Nb/p-GaN Schottky barrier diodes exhibit an ON/OFF current ratio of 2 × 106, an ideality factor of 1.4, and a Schottky barrier height (ΦB) of 1.0 eV extracted from forward current–voltage (I–V) measurements. Despite the moderate barrier height, the reverse leakage current density is strongly suppressed, reaching 1.5 × 10−6 A/cm2 at −2.5 V, indicating that carrier transport is governed by the ensemble-averaged barrier rather than localized low-barrier patches. Capacitance–frequency (C–F) and conductance–frequency (G–F) measurements reveal Dit of ∼1012–1013 cm−2 eV−1, such that trap-assisted processes do not dominate carrier transport. Temperature-dependent electrical measurements confirm thermionic-emission (TE) dominated conduction over a wide bias and temperature range, with negligible barrier degradation. Unlike conventional Schottky metals on p-GaN, where reverse transport is frequently governed by barrier inhomogeneity and field-assisted leakage, Nb yields an electrically stable interface with suppressed trap activity without post-metallization annealing. The central novelty of this work lies in demonstrating that Nb enhances p-GaN Schottky performance by stabilizing the barrier landscape through trap depletion and spatial homogenization rather than barrier height maximization. These findings establish Nb as a performance-optimized Schottky metal for p-GaN rectifiers and gate interfaces.

ABSTRACT Controlling peroxymonosulfate (PMS) activation at the atomic scale is crucial for steering reactive oxygen species (ROS) pathways, yet design principles that selectively bias PMS chemistry toward interfacial radical states remain elusive. Herein, we report an asymmetric Fe–Te dual‐atom pair (FeTe DAs/NC), in which a p‐block metalloid electronically modulates an Fe center through pronounced p–d hybridization. This atomic asymmetry reconstructs the local electronic structure, strengthens PMS binding, and directs PMS activation toward the generation and retention of surface‐bound hydroxyl radicals. Mechanistic studies reveal surface‐bound hydroxyl radicals ( • OH) as the dominant ROS, while singlet oxygen ( 1 O 2 ) plays a secondary role. As a result, FeTe DAs/NC achieves complete degradation of carbamazepine within 60 min, markedly outperforming Fe or Te single‐atom analogs, together with excellent reactivity and cycling stability across different water matrices and pollutant systems. This work establishes atomic‐scale asymmetry and metal–metalloid p–d coupling as an effective strategy for steering PMS activation chemistry toward long‐lived interfacial radical states.

HighlightsaPost-metallization annealing achieves a positive VFB shift of up to 390 mV for threshold voltage modulation.La-FMD treatment enables equivalent oxide thickness (EOT) scaling of approximately 1.3 Å without increasing physical thickness.Interface quality is improved, with interface state density (Dit) reduced by 51.2% and oxide trap density (Not) reduced by 45.8%.Annealing-induced La redistribution forms HfLaOx, weakening dipole strength and enabling tunable VFB control.

Determination of interface state density of MXene and polyaniline nanocomposite/p-Si diode by advanced Fytronix amplitude method

2D monolayers of tin monochalcogenides (SnX, with X = S, Se, and Te) offer environmental stability, making them promising for various technological applications. Although proposed as ferroelectrics, their nonlinear optical (NLO) activity has not been fully explored. Here, we use density functional theory to quantify their NLO response by calculating the (hyper)polarizability. These monolayers are semiconducting and form a stable Type II heterostructure with TiO2(001), which is advantageous because it effectively suppresses electron-hole recombination in a device. The interfacial electronic states, created by the interaction of the (Sn) lone pair electrons with the substrate's electronic states, lead to increased polarizability (α) and first dipole hyperpolarizability (β) of the supported monolayers. Additionally, a significant enhancement in both β (-ω; ω, 0); β (0; 0, 0), and β (-2ω; ω, ω) is predicted for the supported SnSe monolayer. This may be due to a resonance effect associated with an interfacial charge-transfer transition, which appears to be closely aligned with the incident photon energy at λ = 1064 nm. This overall amplification of the NLO response indicates that these supported chalcogenide monolayers are promising candidates for next-generation nanoscale photonic technologies.

As a fundamental phenomenon in nature, chirality has been extensively studied in molecular structures; however, it remains underexplored at the electronic level. Understanding how structural chirality transfers into electronic states is crucial for uncovering the essence of many chiral effects. In this study, we report the engineering and direct visualization of chiral electronic states within an otherwise planar, achiral hexa-peri-hexabenzocoronene (HBC) framework. By employing atomically precise asymmetric nitrogen doping of HBC through on-surface synthesis, we fabricate a C3-symmetric triaza-HBC on Au(111). Utilizing high-resolution scanning tunneling microscopy and non-contact atomic force microscopy, we resolve the chiral molecular structure of triaza-HBC confined to the surface, as well as the chiral texture of the resulting interfacial electronic states and its evolution at different energies. Density functional theory calculations reveal that these electronic chiral features arise from the molecule's intrinsic chiral orbitals, which hybridize strongly with the metal substrate while still retaining their chiral character. This study not only demonstrates a clear transfer of chirality from molecular structure to the electronic landscape but also provides a versatile platform for the rational design of chiral electronic molecules and materials.

ABSTRACT As a fundamental phenomenon in nature, chirality has been extensively studied in molecular structures; however, it remains underexplored at the electronic level. Understanding how structural chirality transfers into electronic states is crucial for uncovering the essence of many chiral effects. In this study, we report the engineering and direct visualization of chiral electronic states within an otherwise planar, achiral hexa‐ peri ‐hexabenzocoronene (HBC) framework. By employing atomically precise asymmetric nitrogen doping of HBC through on‐surface synthesis, we fabricate a C 3 ‐symmetric triaza‐HBC on Au(111). Utilizing high‐resolution scanning tunneling microscopy and non‐contact atomic force microscopy, we resolve the chiral molecular structure of triaza‐HBC confined to the surface, as well as the chiral texture of the resulting interfacial electronic states and its evolution at different energies. Density functional theory calculations reveal that these electronic chiral features arise from the molecule's intrinsic chiral orbitals, which hybridize strongly with the metal substrate while still retaining their chiral character. This study not only demonstrates a clear transfer of chirality from molecular structure to the electronic landscape but also provides a versatile platform for the rational design of chiral electronic molecules and materials.