The AC-driven rotating gliding arc (AC-RGA) reactor offers advantages in simplifying discharge systems and reducing energy losses. Using CO2 as the working gas, this study examines how gas flow rate and inlet configuration influence arc dynamics, electrical behavior, and CO2 conversion. Compared with the single-inlet design, the four-inlet configuration generates a more uniform flow field, stabilizing arc rotation, reducing voltage fluctuations, and enhancing CO2 conversion and energy efficiency. Optical emission spectroscopy and exhaust temperature analyses indicate that the uniform flow suppresses CO and O recombination while promoting CO2 + formation, thereby improving decomposition efficiency and highlighting the importance of flow uniformity in optimizing AC-RGA performance.

The pervasive contamination of aquatic environments by pharmaceutical residues, particularly antibiotics, necessitates the development of efficient and sustainable advanced oxidation technologies. Here, an integrated plasma-microbubble system was developed by coupling atmospheric-pressure dielectric barrier discharge (DBD) with a Venturi-based microbubble generator. With intensified gas-liquid interfacial interactions, the integrated system achieved 99.5% degradation of tetracycline (TC) (100 mg/L) within 10 min, corresponding to a 47.4% enhancement relative to DBD plasma alone. The introduction of microbubbles elevated the degradation performance of air discharge to a level approaching that of pure oxygen plasma, underscoring the efficacy of microbubble integration. Combined analysis of discharge products and scavenger experiments substantiated the enhanced interfacial mass transfer and highlighted O-2(-) and center dot OH as the key reactive species governing degradation. Density functional theory (DFT) calculations combined with liquid chromatograph mass spectrometer (LCMS) analysis elucidated transformation pathways at the molecular level. Furthermore, antibacterial assays and quantitative structure - activity relationship (QSAR) modeling confirmed a substantial reduction in biological activity and ecotoxicological risk following treatment. By integrating interfacial regulation with systematic mechanistic and toxicity assessment, this work advances the rational design of energy-efficient multiphase plasma reactors.

Membrane-based techniques have been playing an important role in desalination. The feed spacer in membrane modules not only separates membrane sheets to form feed channels but also acts as a turbulence promoter, enhancing flow mixing, mass transfer, and thereby reducing concentration polarization. Optimizing feed spacer design is essential for controlling the membrane fouling and lowering the energy consumption. In this study computational fluid dynamics (CFD) was exploited to optimize spacer configurations; 3D printing was employed to fabricate spacer in terms of the novel designs inspired by airplane wing aerodynamics; fluid dynamics experiments were performed to assess their effects on the flow parameters. The relationship between the flow parameters, membrane hydraulic performance, and anti-fouling properties was analyzed to reveal a trade-off between the pressure-drop reduction and fouling resistance. The design comparison indicated that wing-like designs had minimal impact on membrane permeability, while COM-M1 and COM-M2 increased reverse osmosis (RO) membrane flux by up to 19.8%. Fouling experiments further demonstrated that nanofiltration (NF) membranes, with looser separation layers, could be more prone to concentration polarization thanRO membranes, particularly after humic acid fouling. All these findings offer a basis for feed spacer optimization and provide critical insights for matching the spacer design with different membrane processes.

Electrochemical ammonia synthesis from nitrate (NO3RR) can only decarbonize NH3 when nitrate is renewably generated from air. Here we integrate air plasma oxidation with electrocatalytic nitrate reduction and treat two constraints as one design problem: oxidant speciation entering the absorber and proton supply at the electrocatalyst interface. Five air discharges were assembled and their gas- and liquid-phase outputs were analyzed. Under alkaline capture, a parallel dielectric-barrier/gliding-arc reactor preserved ozone, increased NO2 and N2O5 at the gas-liquid interface, and produced a nitrate-nitrite electrolyte used directly without reconditioning (13.86 +/- 0.72 mmol h(-1) NOx- at 2.38 +/- 0.04 kWh mol(-1)). To favor the *NO ->*NHO step over H-2 evolution, we constructed hydroxide-on-copper nanowire heterostructures that place proton-donor motifs adjacent to nitrate-activating Cu sites. Ni(OH)(2)@Cu NWs outperformed Co(OH)(2)@Cu NWs and Cu NWs, reaching similar to 87.6 % FE at -1.1 V vs RHE (0.51 +/- 0.03 kWh mol(-1) NH3) with an NH3 yield of similar to 5.18 mmol h(-1) cm(-2). DFT indicates a 0.12 eV barrier for *NO ->*NHO at the Ni(OH)(2)-Cu junction, and quasi-in-situ ESR supports enhanced interfacial *H formation/consumption. Overall, combining proton-economy electrocatalysis with speciation-controlled plasma oxidation yields a specific energy consumption of 2.89 kWh mol(-1) NH3.

Electrochemical nitrogen reduction under ambient conditions is constrained by the kinetic inertness of N2 and competition from the hydrogen evolution reaction. Here, we report an integrated plasma-electrolysis membrane-electrode assembly that couples a microstructured nonthermal surface discharge directly to a gas-diffusion cathode, enabling in situ generation and delivery of vibrationally excited N2, N2(ν), to the electrocatalytic interface. Among 14 metal catalysts screened, Ag provided the best balance of activity and selectivity, achieving an NH3 production rate of 7.7 ± 0.8 nmol s-1 cm-2 with an electrochemical Faradaic efficiency of 86 ± 14% at -0.54 V versus RHE under atmospheric pressure and room temperature. Plasma/electrolysis on-off controls and 15N2 isotope-labeling experiments establish that NH3 formation requires simultaneous plasma activation and electrochemical polarization and originates from the supplied N2. Plasma-kinetic modeling indicates strong vibrational excitation in the discharge, with a calculated effective vibrational temperature of approximately 4300 K and 11.8% of N2 occupying levels (ν = 4-8). Transport modeling further suggests that these comparatively long-lived excited states persist to the membrane-catalyst region. In situ Raman spectroscopy reveals N-N-containing surface intermediates only during coupled operation, while density functional theory shows that vibrational excitation lowers the free-energy requirement for the initial hydrogenation of N2 to *NNH and shifts the rate-determining step in a catalyst-dependent manner. These findings establish vibrational-state engineering as a strategy for coupling non-equilibrium molecular activation with electrocatalysis for distributed ammonia synthesis under ambient conditions.

Electrochemical nitrogen reduction under ambient conditions is constrained by the kinetic inertness of N2 and competition from the hydrogen evolution reaction. Here, we report an integrated plasma-electrolysis membrane-electrode assembly that couples a microstructured nonthermal surface discharge directly to a gas-diffusion cathode, enabling in situ generation and delivery of vibrationally excited N2, N2(nu), to the electrocatalytic interface. Among 14 metal catalysts screened, Ag provided the best balance of activity and selectivity, achieving an NH3 production rate of 7.7 +/- 0.8 nmol s-1 cm-2 with an electrochemical Faradaic efficiency of 86 +/- 14% at -0.54 V versus RHE under atmospheric pressure and room temperature. Plasma/electrolysis on-off controls and 15N2 isotope-labeling experiments establish that NH3 formation requires simultaneous plasma activation and electrochemical polarization and originates from the supplied N2. Plasma-kinetic modeling indicates strong vibrational excitation in the discharge, with a calculated effective vibrational temperature of approximately 4300 K and 11.8% of N2 occupying levels (nu = 4-8). Transport modeling further suggests that these comparatively long-lived excited states persist to the membrane-catalyst region. In situ Raman spectroscopy reveals N-N-containing surface intermediates only during coupled operation, while density functional theory shows that vibrational excitation lowers the free-energy requirement for the initial hydrogenation of N2 to *NNH and shifts the rate-determining step in a catalyst-dependent manner. These findings establish vibrational-state engineering as a strategy for coupling non-equilibrium molecular activation with electrocatalysis for distributed ammonia synthesis under ambient conditions.

The escalating climate crisis driven by CO2 emissions necessitates performance- and energy-efficient carbon utilization technologies. Catalytic CO2 reduction and valorization into value-added organic acids hold significant promise, yet current systems often require precious metal catalysts, high temperatures, or elevated pressures. Herein, we demonstrate a catalyst-free plasma-electrochemical process for the one-step organic acid synthesis from CO2 and H2O under ambient conditions. This approach employs a gaseous plasma electrode powered by a negative DC source, coupling plasma excitation in the gas phase with solvated electron-induced CO2 reduction in the liquid. Through systematic optimization of key parameters, including electrolyte conductivity, alkali metal cation type, pH, temperature, and discharge configuration, the process achieves an oxalic acid formation rate of 71.68 mu mol/h. Mechanistic studies, including product profiling and radical scavenging experiments, reveal that oxalic acid formation proceeds predominantly via solvated electron-mediated CO2 coupling through CO2- intermediates, while formic acid is generated from CO2- and CO hydrogenation. We expect that this work could establish a sustainable route for ambient-condition CO2 conversion using plasma-enabled electrochemistry, advancing the field of catalyst-free carbon valorization.

This work demonstrates a new catalyst-free pathway of urea synthesis via direct CO2/N2 coupling in spatially separated dual plasma reactors. The design isolates reactive species generation, suppressing oxidative side reactions (e.g., O and OH-induced NH3 loss) and facilitating C-N coupling. Mechanistic studies indicate CO (from CO2 dissociation) as the key intermediate, reacting with NHx to form urea, while minimizing NOx byproducts. By decoupling plasma zones, the system achieves selective nitrogen fixation under ambient conditions, advancing green urea synthesis without catalysts or extreme energy inputs. This strategy provides mechanistic insights and a scalable platform for sustainable carbon/nitrogen co-utilization.

Given its significant environmental and economic impact, substantial research has been dedicated to improving the Haber–Bosch process. Leveraging the advantages of renewable energy sources and sustainable feedstocks, plasma catalysis is emerging as a promising green technology for small-scale, onsite nitrogen (N₂) fixation. However, current plasma-catalysis applications for nitrogen fixation face several challenges. These include high energy consumption for hydrogen (H2) production prior to ammonia synthesis, low energy efficiency, and a limited understanding of the underlying mechanisms. In this study, we compare two green chemical pathways for plasma catalysis in NH3 and NOx production and their effective storage in water from a plasma chemistry modeling perspective. Our model incorporates both electron and vibrational kinetics, along with updated surface reactions based on Density Functional Theory (DFT) calculations. These calculations consider catalytic ruthenium (Ru) on MgO supports and non-catalytic SiO2 as a reference for ammonia synthesis and titanium dioxide (TiO2) for NOx synthesis. We will evaluate and discuss key intermediates and pathways for producing high-density NH3 and NOx, and suggest opportunities for further improvement.

The generation of micronano bubbles (MNBs) typically relies on cavitation processes. However, discharge inside an underwater bubble causes bubble deformation, providing a new avenue for MNB formation. This study introduces a novel mechanism for micronano bubbles (MNB) generation through self-sustained discharge processes with underwater bubbles. High-speed imaging reveals the dynamic interplay between spark discharge formation and bubble structural evolution. A local thermal equilibrium (LTE) plasma model provides insights into the thermal and electrical dynamics during bubble rupture. The model demonstrates that, local temperature increases, up to 1750 K of a plasma gas temperature, resulting from discharge streamer activity within bubble cavities. Velocity streamlines near the bubble neck following its expansion at elevated temperatures indicate the initial position of the bubble breakup. The MNBs significantly enhance the dissolution and generation of reactive species, including O3 and H2O2 in the solution, highlighting their potential to enhance interfacial reactions and water disinfection applications.

Abstract Regulating favorable assemblies of metallic atoms in the liquid state provides promise for catalyzing various chemical reactions. Expanding the selection of metallic solvents, especially those with unique properties and low cost, enables access to distinctive fluidic atomic structures on the surface of liquid alloys and offers economic feasibility. Here, Sn solvent, as a low-cost commodity, supports unique atomic assemblies at the interface of molten SnIn0.1034Cu0.0094, which are highly selective for H2 synthesis from hydrocarbons. Atomistic simulations reveal that distinctive adsorption patterns with hexadecane can be established with Cu transiently reaching the interfacial layer, ensuring an energy-favorable route for H2 generation. Experiments with a natural oil as feedstock underscore this approach’s performance, producing 1.2 × 10− 4 mol/min of H2 with 5.0 g of catalyst at ~93.0% selectivity while offering reliable scalability and durability at 260 °C. This work presents an alternative avenue of tuning fluidic atomic structures, broadening the applications of liquid metals.

Liquid nitrogen fertilizers, such as potassium nitrate (KNO3) have been commonly used in modern agriculture, playing a crucial role in agricultural production. However, its production involves energy-intensive and environmentally unfriendly processes such as the Haber-Bosch process. This study demonstrated a new strategy for the sustainable and distributed production of liquid KNO3 fertilizer via air plasma bubbles. We investigated the effects of solution characteristics (initial liquid conductivity, pH) and discharge power on the nitrogen fixation performance of the air plasma bubble system. Using a strongly alkaline solution can induce the increase of vibrational temperature (Tvib) during air plasma discharges, thereby enhancing NOx yield together with favoring the NOx adsorption process. Moreover, through electrical characteristics and a simplified circuit diagram, we found a highly conductive liquid phase is not conducive to NOx generation due to the significant energy dissipation in the liquid before discharge. By further adjusting discharge power parameters and coupling the introduction of O3, the highest energy efficiency (58.5 mmol kWh-1) of NOx production, with an excellent production rate (1687.4 mu mol h-1) is achieved. These findings provide an overall understanding of the effects of solution characteristics on gas-liquid plasma chemistry and pave the way for the optimized production of liquid nitrogen fertilizers.

Ammonia is the cornerstone of modern agriculture,providing a critical nitrogen source for global food production and serving as a key raw material for numerous industrial chemicals.Electrocatalytic nitrate reduction,as an environmentally friendly method for synthesizing ammonia,not only mitigates the reli-ance on current ammonia synthesis processes fed by traditional fossil fuels but also effectively reduces nitrate pollution resulting from agricultural and industrial activities.This review explores the fundamen-tal principles of electrocatalytic nitrate reduction,focusing on the key steps of electron transfer and ammonia formation.Additionally,it summarizes the critical factors influencing the performance and selectivity of the reaction,including the properties of the electrolyte,operating voltage,electrode mate-rials,and design of the electrolytic cell.Further discussion of recent advances in electrocatalysts,includ-ing pure metal catalysts,metal oxide catalysts,non-metallic catalysts,and composite catalysts,highlights their significant roles in enhancing both the efficiency and selectivity of electrocatalytic nitrate to ammo-nia(NRA)reactions.Critical challenges for the industrial NRA trials and further outlooks are outlined to propel this strategy toward real-world applications.Overall,the review provides an in-depth overview and comprehensive understanding of electrocatalytic NRA technology,thereby promoting further advancements and innovations in this domain.

Discharge modes of surface dielectric barrier discharge are influenced by various factors, with its underlying mechanisms still unclear. This study explores the effects of power input and N-2/O-2 ratios on NOx yield and selectivity using Fourier Transform Infrared Spectroscopy and analyzes the spatiotemporal evolution of discharges under alternating current (AC) and pulsed power sources. Results show that NO2 selectivity is higher under pulsed power compared to AC, with a peak of 56.2% at 30% N-2 content. Increased power enhances NO2 selectivity to 49.6% in the pulsed-driven system, while no significant change is observed with AC. The lower rotational temperature in pulsed power systems facilitates the O generation for further NO oxidation. These findings may provide new chemical insights into plasma-enabled nitrogen oxidation.

The escalating challenges posed by water resource contamination, especially exacerbated by health concerns associated with microbial fungi threats, necessitate advanced disinfection technologies. Within this context, non- thermal plasma generated within bubble column reactors emerges as a promising antifungal strategy. The effects of direct plasma bubbles within different discharge modes and thus-produced plasma activated water (PAW) on the inactivation of Saccharomyces cerevisiae are investigated. Results show that plasma bubbles generated by dielectric barrier discharge (DBD) mode can effectively inactivate yeast cells (similar to 4.44 logs reduction) within 1 min, outperforming the spark discharge (SD). In this case, SD can cause a significant portion of cell necrosis, possibly due to the high electric field at the bubble interface. In PAW, DBD and SD produce different dominant long-lived oxygen and nitrogen species, while the crucial short-lived species in yeast apoptosis are both attributed to the singlet oxygen (O-1(2)) as confirmed by scavenger tests. The detection of intracellular reactive oxygen species and antioxidant enzymes further illustrates the role of PAW in triggering apoptosis. Overall, this study demonstrates the discharge mode-dependent modulation of reactive species chemistry in plasma-liquid interactions and provides new insights into the subcellular mechanism of plasma-enabled yeast inactivation for water resource decontamination.

Conventional Haber–Bosch/Bosch–Meiser routes link global urea production to fossil fuel‐based ammonia, accounting for ≈2% of the world's energy use and ≈1.5% of CO 2 emissions. A modular, fully electrified alternative is charted that cleaves the problem at its natural fault line: a non‐thermal plasma first upgrades air to nitrate, then a CO 2 /NO 3 − co‐electrolyzer stitches the two C─N bonds of urea at ambient conditions. The lens is deliberately cross‐disciplinary: every bottleneck is probed with the question, “Has a cognate field already cracked this?” If so, how can the solution be mirrored here? Plasma physics contributes to vibrational pumping, power modulated reactors, and in water quenching; CO 2 and nitrate electro‐reduction supply relay‐site catalyst design, vacancy tuning, and pulsed‐bias choreography; flow‐battery engineering guides carbonate‐resilient gas‐diffusion electrodes (GDEs) and zero‐gap membrane‐electrode assemblies (MEAs); and analytical chemistry adds two‐probe assays that unmask false‐positive amine/amide signals. Stitching these advances together, techno‐economic modeling shows that sub‐megajoule plasmas, ≥70% urea‐selective in the electrolyzer, and renewable electricity (RE) at ≤3.5¢ kWh −1 can push green urea below the fossil‐based benchmark.

Abstract This article discusses the ‘power-to-X’ (P2X) concept, highlighting the integral role of non-thermal plasma (NTP) in P2X for the eco-friendly production of chemicals and valuable fuels. NTP with unique thermally non-equilibrium characteristics, enables exotic reactions to occur under ambient conditions. This review summarizes the plasma-based P2X systems, including plasma discharges, reactor configurations, catalytic or non-catalytic processes, and modeling techniques. Especially, the potential of NTP to directly convert stable molecules including CO2, CH4 and air/N2 is critically examined. Additionally, we further present and discuss hybrid technologies that integrate NTP with photocatalysis, electrocatalysis, and biocatalysis, broadening its applications in P2X. It concludes by identifying key challenges, such as high energy consumption, and calls for the outlook in plasma catalysis and complex reaction systems to generate valuable products efficiently and sustainably, and achieve the industrial viability of the proposed plasma P2X strategy.

ObjectiveThe aim of the study is to identify the hospitalized children at risk of peripheral intravenous catheter (PIVC) complications by severity prediction.MethodsThe study included the data of 301 hospitalized children with PIVC complications in 2 tertiary teaching hospitals. A researcher-designed tool was used to collect risk factors associated with PIVC complications. Predictors of PIVC complications at univariate analysis and multivariable logistic regression analysis by backward stepwise. A nomogram was constructed based on the results of the final multivariable model, making it possible to estimate the probability of developing complications.ResultsA total of 182 participants (60.5%) had a moderate injury from PIVC complications. Multivariable logistic regression analysis indicated that the vascular condition, limb immobilization, needle adjustment in venipuncture, infusion length, infusion speed, and insertion site were independent predictors. The nomogram for assessing the severity of PIVC complications indicated good predictive accuracy (area under the curve = 0.79) and good discrimination (concordance index = 0.779). Decision curve analysis demonstrated that the nomogram was a good clinical value with a wide range of threshold probabilities (4%-100%).ConclusionsThe risk prediction model has good predictive performance, and the nomogram provides an easy-to-use visualization to identify the severity of PIVC complications and guide timely nursing care management.

AbstractLiquid fertilizers, particularly when integrated with precision irrigation systems, offer a more efficient and sustainable alternative to traditional solid nitrogen fertilizers. The industrial production of ammonium nitrate (NH4NO3) is environmentally detrimental due to its reliance on fossil fuels. This study introduces an innovative air‐to‐NOx‐to‐NH4NO3 pathway for synthesizing liquid nitrogen fertilizer. The process employs an underwater multi‐bubble plasma reactor powered by nanosecond pulse to generate aqueous NOx, which is then partially reduced to NH4NO3 through electrocatalysis. Results show that the highest NOx production rate, 786.5 mol h−1, is achieved when the N2/O2 ratio closely resemble that of air, and short pulse rise/fall times significantly increase NOx yield. Further plasma diagnostic and global plasma chemistry modeling indicate that short rise/fall times facilitate simultaneous dielectric barrier discharge and spark discharge, synergistically enhancing nitrogen fixation efficiency. The partially electro‐reduced liquid NH4NO3 fertilizer significantly improves plant growth, with stem length and leaf length increasing by 91.26% and 54.72%, respectively. Cost estimation reveals that 44.22% of the production cost is attributed to electricity consumption, underscoring the potential for optimization with renewable energy integration. Overall, the study provides new insight for the sustainable production and in‐place utilization of liquid nitrogen fertilizers which may advance sustainable agriculture.

The production of ammonia, powered by renewable energy, in a decentralized manner is of key importance in the transition to a more sustainable future. Recent research has explored the integration of non-thermal plasma and electrochemical processes to achieve this goal. However, the success of this hybrid process is contingent on the energy efficiency of the plasma-generated species. Herein, we developed a plasma bubble reactor, driven by nanosecond pulses interfacing plasma directly with water. This reactor can comprehensively probe gas ionization processes, different energy channels, corresponding plasma catalytic reaction mechanisms, and reactive species in gas and liquid phases. By using on-and-off plasma ignition with rapid pulses, we could regulate energy consumption in cycles and achieved the lowest reported energy consumption of 2.7 +/- 0.1 kWh mol(-1) NO3- and 3.2 +/- 0.1 kWh mol(-1) NH4+ after electrocatalytic nitrate reduction. This provides a promising pathway to producing green, renewable ammonia from air and water.