The superhydrophobic of plant leaves, such as those of rice and lotus, has long been attributed to surface micro-nano structures and wax layers. Here, we reveal a previously overlooked determinant─surface polarity─as the principal factor governing leaf wettability. Through controlled oxygen plasma exposure, we demonstrate reversible switching between hydrophobic and hydrophilic states on multiple plant species without altering their intrinsic surface topography, as confirmed by scanning electron microscopy. Surface charge characterization indicates that plasma treatment introduces uniform positive charges, which dictates the transition toward hydrophilicity. Subsequent charge removal via electrical grounding restores the original hydrophobic state, a reversible process that remains stable over hundreds of cycles. These findings challenge the classical structural model and establish surface polarity as the central mechanism for dynamic wettability control on biological surfaces. This approach offers promising utility in agriculture by enabling precise modulation of droplet-leaf interactions, thereby enhancing pesticide adhesion and utilization efficiency. Our work not only advances fundamental understanding of biointerfacial phenomena but also provides a scalable strategy for sustainable agrochemical management.

ABSTRACT Due to the inherent bandgap limitations of traditional semiconductors, achieving a broadband response typically requires complex heterostructures, which suffer from lattice mismatch and compromised performance. Herein, we propose a novel oxygen plasma treatment WSe 2 homojunction strategy to overcome this trade‐off. A simple mask‐assisted magnetron sputtering technique was employed to fabricate an interdigital p‐n homojunction photodetector. The key innovation lies in creating a staggered type‐II band alignment via localized oxygen doping on pure WSe 2 , which effectively promotes charge separation across the broadband. The device exhibits remarkable detectivity values of 4.58×10 9 Jones (365 nm), 3.57×10 10 Jones (470 nm), 1.29×10 11 Jones (550 nm), 1.13×10 12 Jones (850 nm), and 1.52×10 12 (1064 nm) at a bias of 0 V. Clear “HIT” pixel images with distinct edges were obtained at all these wavelengths. At 1064 nm, the device achieved a high on/off ratio of 2,208 and fast rise/fall times of 59 µs and 18 µs, respectively. Through wide‐spectrum imaging and high‐frequency response testing, the device demonstrates excellent potential for next‐generation, high‐performance broadband imaging systems.

Sustainable management of PET waste via oxygen plasma-enriched PET/rGO/TiO2 counter electrodes in DSSCs.

Reusable SERS substrates based on flexible polyamide supports with hierarchical structures for in-situ detection of pesticide residues.

Two-dimensional transition metal dichalcogenides (2D TMDCs) have attracted considerable research interest as key materials for next-generation integrated photonic and optoelectronic devices. However, the atomic layer materials are vulnerable to environmental influences. In addition, their ultimate thinness limits the effective length of light-matter interaction, restricting their emission intensity. Although bulk and few-layer TMDCs exhibit better environmental robustness, they typically suffer from indirect bandgap transitions, resulting in reduced optoelectronic efficiency. In this work, we report an in situ processing strategy to induce direct-bandgap exciton emission from few-layer (2-4 layers) MoS2. A combined approach of mild oxygen plasma treatment and subsequent laser irradiation is employed to modify the few-layer MoS2. Following the treatments, we observed pronounced photoluminescence (PL) emission in the suspended few-layer MoS2, in contrast to the PL quenching effect detected in substrate-supported areas. Such a large difference in PL intensity is attributed to thermally driven interlayer decoupling of the few-layer MoS2, which occurs exclusively in the suspended regions due to their significantly elevated temperature. According to the molecular dynamics simulation study, plasma treatment is essential for interlayer decoupling by injecting oxygen ions into the van der Waals gaps. These oxygen ions can potentially form oxygen molecules under laser-induced heat, leading to the expansion of van der Waals gaps. These findings demonstrate the potential for spatially selective PL enhancement in few-layer MoS2. As a proof of concept, high-contrast PL patterns in bilayer MoS2 were prepared, showcasing its promising application in anti-counterfeiting labeling. Furthermore, this work provides high-performance light-emitting materials for diverse photonic and optoelectronic applications.

Cellulose-based materials are widely used in wound care due to their biocompatibility, biodegradability, and fluid-handling capacity. While chemical functionalisation is commonly employed to impart antimicrobial activity, the role of physical surface modification in regulating bacterial adhesion remains less explored. In this study, low-pressure radiofrequency (RF) oxygen plasma was used as a dry and environmentally friendly approach to modify the surface of medical-grade cellulose without altering its bulk properties. Plasma treatment was performed in both glow and afterglow regions, enabling controlled exposure to reactive oxygen species. Surface modification resulted in pronounced nanoscale roughening and fissured topography of cellulose microfibers, as observed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Plasma-induced oxidation of the cellulose surface, characterised previously by X-ray photoelectron spectroscopy (XPS), accompanied the morphological changes. Bacterial adhesion experiments using a non-pathogenic Escherichia coli model strain revealed significantly enhanced bacterial attachment on plasma-treated cellulose compared to untreated controls, with the strongest effect observed for glow-region treatments. The increased adhesion is attributed to the combined effects of surface roughness amplification and plasma-induced chemical functionalisation, which together increase the effective contact area between bacteria and the substrate. Rather than aiming to inhibit bacterial attachment, this work explores a physico-mechanical design concept in which surface topography is intentionally modified to favour bacterial binding to the dressing material itself. The observed behaviour is interpreted qualitatively using concepts from membrane mechanics as a phenomenological framework, without invoking a quantitative predictive model. While the present study does not assess net bacterial load reduction in wound environments, it establishes a materials-level basis for a “capture-and-remove” hypothesis, whereby preferential bacterial adhesion to a removable dressing could contribute to microbial load management during dressing changes. These findings highlight the potential of plasma surface engineering as a versatile tool for tailoring the biointerface of cellulose-based biomedical materials.

This paper demonstrates roll-to-roll oxygen plasma texturing of commodity and engineering polymer films to create stochastic nanotopographies that enhance solar-weighted trans- mittance and water repellence for coatings applications. Acrylic urethane varnish layers cured by electron beam on polymer webs serve as etchable proxy coatings for substrates that are difficult to plasma-pattern directly, with a surface-active siloxane additive modulating nanostructure morphology during etching. Process-to-performance links are quantified via UV-VIS-NIR spectroscopy, SEM, XRD, and static contact angle, showing broadband antireflection gains alongside large hydrophobic shifts while correlating feature evolution to polymer composition and crystallinity. Outdoor exposure of treated fluoropolymer films retains a transmittance advantage over untreated controls over extended periods, indicating durability of the nanotextured coating function under real weathering. The work provides reproducible, scalable parameters for web-based plasma nanostructuring and varnish-mediated patterning, enabling integration of AR and self-cleaning functionalities into polymer coating stacks for architectural, photovoltaic, and automotive uses.

Cold atmospheric plasma (CAP) shows strain-dependence against Candida albicans growth on titanium.

Low-temperature plasma treatments were applied to barley seeds using a dielectric barrier-stabilized corona discharge operated in ambient air enriched with oxygen or nitrogen to quantify surface chemical modifications and seed wettability. X-ray photoelectron spectroscopy showed that oxygen-enriched plasma produced the strongest oxidation, increasing surface oxygen from 9 ± 5 at% (control) to 24 ± 5 at%, while reducing carbon from 88 ± 5 at% to 76 ± 5 at%. Nitrogen-enriched plasma induced more moderate changes (O: 13 ± 5 at%, C: 85 ± 5 at%) but resulted in clear nitrogen incorporation, with an enhanced N 1s amine/amide component at ~400.8 eV. The hydroxyl O 1s contribution increased from 70% (control) to 82% (oxygen) and 90% (nitrogen), indicating substantial surface hydroxylation. SEM-EDX showed only minor micrometer-scale composition changes and no detectable morphological damage. Raman and ATR-FTIR spectra confirmed that polysaccharide, protein, and lipid structures remained intact, with intensity variations reflecting increased hydrophilicity. Water imbibition kinetics fitted with the Peleg model demonstrated faster initial hydration after plasma exposure, with 1/k1 increasing from 20.25 ± 1.90 h−1 (control) to 36.70 ± 6.56 h−1 (oxygen) and 38.87 ± 7.57 h−1 (nitrogen), while 1/k2 remained nearly unchanged.

ABSTRACT Achieving ultrahigh mobility in oxide semiconductors without sacrificing stability has remained a long‐standing challenge owing to their inherent disorder and the tradeoff between mobility and stability. In this study, we demonstrated for the first time that the completeness of atomic layer deposition (ALD) surface reactions is the key factor for the formation of well‐defined vertical heterostructures in amorphous InGaZnO (IGZO) thin films, which in turn trigger quantum confinement effects and 2Delectron gas (2DEG) like interfacial conduction. By comparing high‐reactivity oxygen plasma and low‐reactivity ozone as oxidants, we revealed that only plasma‐assisted ALD achieved complete surface reactions, yielding atomically ordered InO x– (Ga, Zn)O stacks with distinct interfaces. This engineered structure resulted in an exceptional field‐effect mobility (>87 cm 2 V −1 s −1 ) with positive threshold voltage (0.56 V), an apparent two‐step conduction signature, and superior stability of the positive/negative bias temperature stability of 0.35/−0.01 V. Temperature‐dependent transport from room to cryogenic temperature (83K) and high‐temperature annealing (600°C) further confirmed the correlation among reaction completeness, interface quality, and 2DEG‐like interfacial conduction. This study identifies a critical link between ALD surface chemistry and quantum transport in oxides and provides a novel and practical strategy to overcome the mobility–stability tradeoff in next‐generation oxide transistors.

Neuromorphic computing, an emerging computational paradigm, aims to overcome the bottlenecks of the traditional von Neumann architecture. Two-dimensional materials serve as ideal platforms for constructing artificial synaptic devices, yet existing devices based on these materials face challenges such as insufficient stability. Indium selenide (InSe), a two-dimensional semiconductor with unique properties, demonstrates significant potential in the field of neuromorphic devices, though its application research remains in the initial stage. This study presents an artificial synaptic device based on the InSe/Charge Trapping Layer (CTL)/h-BN heterojunction. By applying oxygen plasma treatment to h-BN to form a controllable charge-trapping layer, efficient regulation of carriers in the InSe channel is achieved. The device successfully emulates fundamental synaptic behaviors including paired-pulse facilitation and long-term potentiation/inhibition, exhibiting excellent reproducibility and stability. Through investigating the influence of electrical pulse parameters on synaptic weights, a structure–activity relationship between device performance and structural parameters is established. Experimental results show that the device features outstanding linearity and symmetry, realizing the simulation of key synaptic behaviors such as dynamic conversion between short-term and long-term plasticity. It possesses a high dynamic range ratio of 7.12 and robust multi-level conductance tuning capability, with stability verified through 64 pulse cycle tests. This research provides experimental evidence for understanding interfacial charge storage mechanisms, paves the way for developing high-performance neuromorphic computing devices, and holds broad application prospects in brain-inspired computing and artificial intelligence hardware.

Abstract Nanowires are widely used in many applications, such us in electronics, photonics and biomedical devices due to their unique structural and surface properties. One key aspect of the performance of nanowires (NWs) is their alignment and vertical orientation relative to the substrate.. A widely used method for surface inspection on nanoscale is Scanning Electron Microscopy (SEM). However, these 2D images offer limited perspective on the 3D alignment and verticality of NWs. To address this limitation, we introduce a quantitative method for the characterization of nanowire alignment and verticality using a hybrid approach combining the analysis of top-down and tilted SEM images.The key idea is that in both types of images, the nanowire verticality is reflected on the anisotropy of their 2D texture, which can be quantified through an anisotropy index based on the 2D Fourier Transform (FT) of SEM images. The developed methodology is applied to evaluate the verticallity of Polymethyl Methacrylate (PMMA) nanowires treated with oxygen plasma and further coated with a carbyne-like layer to increase their durability during water immersion. Our findings demonstrate that the carbyne-like coating significantly enhances NW robustness under immersion conditions, as demonstrated by consistent anisotropy index computations.

Embedding flexible electronic circuits into a sustainable polymer is an emerging and significant topic in the field of in-mold electronics (IME). Ensuring strong adhesion between the flexible circuit and the molded polymer is critical for the durability of IME products. In this study, three different types of etched copper polyimide (PI) foils were used as the substrate of electronic components. Two bio-based and biodegradable polymers of polylactic acid (PLA) and polyhydroxybutyrate (PHB) served as the overmolding material. Four different surface pretreatments: drying, polydopamine (PDA) coating, PDA coating followed by thermal treatment under vacuum, oxygen plasma, and 3-aminopropyltriethoxysilane (APTES) were applied to the PI surface prior to the overmolding process to investigate the influence on the adhesive strength. Additionally, a thermoplastic polyurethane (TPU) adhesive layer was introduced via vacuum lamination to further improve adhesion. The main objective of this study was to evaluate the adhesive strength between etched PI and overmolded biopolymers before and after surface modifications. The loci of failure were analyzed using scanning electron microscopy (SEM). The results indicate that laminated TPU is the most effective approach for improving adhesion between polyimide foils and biopolymers.

Abstract 2D transition metal tellurides (TMTs) exhibit great potential as saturable absorbers (SAs) for mid‐infrared (MIR) pulsed lasers. However, constructing highly stable TMT‐based saturable absorbers (TMT‐SAs) with excellent Q‐switching performance in the MIR region remains challenging. Here, a material design strategy based on oxygen plasma treatment is reported to improve both the stability and MIR Q‐switching performance of 2D TMT‐SAs. This approach involves the direct in situ growth of large‐area, high‐quality 2D ZrTe 3 and TaTe 2 films on CaF 2 substrates as SA mirrors, followed by oxygen plasma passivation. This method circumvents wet‐coating procedures in various previously reported SAs, thereby mitigating the impurity‐induced performance degradation. After oxygen plasma passivation, the ultrathin ZrTe 3 ‐SA (≈30 nm) achieves a peak power of 9.92 W, while the pulse width is reduced to 313 ns. Furthermore, the fabricated 2D TMT‐SAs demonstrate long‐term stability (at least 90 days) under high output power conditions at the ≈3 µm waveband. These findings open possibilities for exploring highly stable MIR‐transparent oxide protective layers for 2D material‐based SAs toward achieving high‐power pulsed lasers.

ABSTRACT Indium gallium zinc oxide (IGZO) thin film transistors (TFTs) with high stability are highly desired for future memory devices, which demand high stabilities. However, residual precursors inevitably present in the dielectric layers deposited by atomic layer deposition (ALD) introduce hydrogen contamination to the devices, thereby impairing their electrical stabilities. In this work, an effective approach is proposed: performing oxygen plasma treatment on the dielectric‐channel interface to suppress hydrogen diffusion, thereby enhancing the electrical stability of IGZO TFTs. X‐ray photoelectron spectroscopy (XPS) results confirm the suppression effect of oxygen treatment on hydroxyl groups, while time of flight secondary ion mass spectrometry (TOF‐SIMS) revealed a 16.46% reduction in hydrogen content within the treated Al 2 O 3 layer. The devices after treatment exhibited a field‐effect mobility (µ eff ) of 17.4 cm 2 /V·s, a threshold voltage (V TH ) of −0.04 V, and a subthreshold swing (SS) of 84.7 mV/dec, with an optimized oxygen plasma power of 50 W. The positive bias temperature stability of the device is significantly promoted due to reduced hydrogen content. The V TH shift (ΔV TH ) is merely 3.5 mV under a bias electric field of 2 MV/cm for 10 000 s. Such treatment provides a promising solution for the integration of IGZO TFTs with Si‐based electronics.

Hemp is a lignocellulosicfiber used in fiber-reinforced composites,technical textiles, and clothing with surface properties that canbe modified by plasma to improve processability. In contrast to previousstudies reporting the effects of short-duration plasma treatment (<10min), this paper investigates the effects of extended (30 min–4h), low-pressure (∼0.4 mbar) argon and oxygen plasma treatmentson dew retted hemp fibers at varying power levels (40 and 80 Hz).Scanning electron microscopy (SEM) revealed marked surface fiber etchingafter prolonged treatment, with argon plasma inducing fibrillationand heterogeneous motifs, while oxygen plasma yielded irregular morphologies.Atomic force microscopy (AFM) confirmed a near 4-fold rise in surfaceroughness (70 to 270 nm) after 4 h of plasma treatment. All plasma-treatedfibers exhibited complete wetting (water contact angle θ = 0°)versus θ = 62° for untreated controls, based on drop-shapeanalysis and tensiometry. Fourier transform infrared spectroscopy(FT-IR) revealed no major chemical shifts, although sharper −OHand −CO peaks suggested a subtle physicochemical change.X-ray diffraction indicated slightly enhanced crystallinity withoutcrystallite size alteration. Fiber tensile strength remained unaffectedacross treatments. Fluorescence microscopy suggested a degree of ligninremoval, evidenced by reduced surface fluorescence after 4 h of argonplasma treatment. Thus, long-duration argon and oxygen plasma treatmentsdistinctly modify hemp fiber surfaces, without substantially alteringinternal chemistry or crystallinity. These findings highlight plasmatreatment as an alternative to wet chemical methods for surficialhemp fiber modification, offering potential for precise surface engineeringin textile applications.

Conventional thermoplastics treated with plasma undercontrolledconditions have proven to be low-cost materials with advanced propertiesthat are highly useful in engineering in applications ranging fromfood packaging to the electrochemical detection of bioanalytes. However,the changes induced by plasma in their chemical structures are stillrelatively unknown. In this work, we address the study of these materials,focusing on poly­(lactic acid) (PLA), which is electrochemically inertbut, once treated with low-pressure oxygen plasma, is capable of detectingbioanalytes such as dopamine based on the acquired electrochemicalresponse. More specifically, we have studied the chemical structureof PLA treated with different low-pressure plasmas using X-ray photoelectronspectroscopy, in-depth micro-Raman, ζ-potential, electricalresistance, and contact angle measurements, proving also the performanceof this material as an electrochemical sensor for detecting dopamine.In addition, we performed atomistic molecular dynamics simulationsto compare the structural properties of plasma-treated PLA with thoseof amorphous and crystalline PLA. The results revealed the formationof specific functional groups at depths up to 10 μm and showedvariations in the material’s electrical properties as well.Additionally, simulation studies revealed that the structure of plasma-treatedPLA differs from those of amorphous and crystalline PLA in terms ofinteractions and conformational order/disorder.

HighlightsWhat are the main findings?Neutral O2 does not alter the emission or structure of CsPbBr3 QD films even under UV illumination.Reactive oxygen species (ROS) cause rapid PL quenching and lifetime shortening.ROS create Br vacancies and Pb–O bonds, generating deep nonradiative traps.What are the implications of the main findings?Oxygen-induced degradation originates from activated oxygen, not molecular O2.Plasma processing conditions must be carefully controlled to avoid ROS damage.Strategies such as passivation and encapsulation can preserve perovskite stability.The chemical identity of oxygen species plays a decisive role in determining the optical stability of halide perovskite QD films. Here, real-time in situ spectroscopic monitoring, together with steady-state and time-resolved photoluminescence measurements, is utilized to differentiate the effects of molecular oxygen and plasma-activated oxygen species on CsPbBr3 QD films. The films maintain nearly unchanged emission intensity, spectral profile, and carrier lifetimes when stored in vacuum or exposed to molecular O2 even under UV illumination, demonstrating that neutral O2 exhibits minimal reactivity toward the [PbBr6]4− framework. In contrast, oxygen plasma generates highly reactive atomic and ionic oxygen species that induce rapid and spatially heterogeneous photoluminescence quenching. This degradation is attributed to Br− extraction, Br-vacancy formation, and subsequent Pb–O bond generation, which collectively introduce deep trap states and enhance nonradiative recombination. These findings clearly indicate that reactive oxygen species rather than molecular O2 are the dominant driver of oxygen-induced luminescence degradation, providing mechanistic insight and offering processing guidelines for the reliable integration of perovskite nanomaterials in optoelectronic devices.

With the development of artificial intelligence and flexible electronics, MXene-based memory devices have gained widespread attention due to their excellent performance. However, the traditional MXene-based memory device often requires high-temperature annealing processes, which hinder their application of memory devices in flexible electronics. Here, we demonstrate the use of a one-step process oxygen plasma (O plasma) irradiation process to induce controlled defects for fabricating MXene-based memory devices directly on a flexible polyimide substrate. The resulting memory device exhibits stable resistive switching behavior with a high switching ratio (∼7.8 × 104), low power consumption (∼49.8 nW), excellent retention performance (30 days), and multi-level storage capability. Additionally, the device maintained high stability after multiple bending tests and shows no significant degradation even after three months of ambient exposure without encapsulation. This work provides a viable strategy for developing flexible, high-performance memory device with high controllability.

Oxygen plasma induced MoS2/MoOx heterojunction for high performance SERS application.