The non-uniform distribution of internal physical fields caused by the interconnects in solid oxide fuel cell (SOFC) stacks remains a major bottleneck hindering their large-scale commercialization. Drawing inspiration from the capillary networks of mammalian lungs, this study proposes a novel vertical-enhanced interdigitated interconnector (VEII), which transforms the traditional diffusion-dominated mass transfer process under the ribs of straight channel interconnector (SCI) into a combined process of forced convection and diffusion. At 1023 K and 0.6 V, the VEII increases the power density by 15.1% relative to the conventional SCI and extends the service lifetime above 97% of the initial performance by 20%. A multi-objective optimization of VEII geometry via response surface methodology yields the optimal dimensions: rib width 0.5 mm, distributor width 0.7 mm, rib height 1.9 mm, and distributor height 0.8 mm. After optimization, compared with SCI-SOFC, the VEII-SOFC delivers an additional 26% gain in power density at 0.6 V and a 71.47% reduction in stack pressure drop. Detailed analysis indicates that the VEII-SOFC effectively shortens the diffusion distance of reactant gases in the porous electrodes and alleviates the anoxic zones under the ribs. As a result, the VEII-SOFC homogenizes the spatial distribution of temperature, reactant gases, and equilibrium potential within the stack, thereby significantly improving the electrochemical performance and extending the service lifetime of the stack. These advantages highlight the application potential of the VEII-SOFC.

Despite their immense potential for clean and efficient energy conversion, the widespread commercialization of solid oxide fuel cells (SOFCs) is hindered by limited electrochemical performance at intermediate and low temperatures. The development of high-performance and stable cathode materials is crucial for advancing intermediate-temperature proton-conducting SOFCs (IT-PC-SOFCs). A series of LnBaFe(2)O(5+delta) (LnBF) materials with A-site doping by different rare-earth elements (Ln = La, Pr, Nd, Sm, Gd) was successfully synthesized. The influence of the A-site ionic radius on the crystal structure, microstructure, elemental valence states, thermal stability, and oxygen vacancy formation capability was systematically investigated. The results indicate that the selection of the A-site dopant is a critical factor, as it effectively modulates the Fe3+/Fe4+ mixed-valence ratio and oxygen vacancy concentration. Density functional theory (DFT) calculations further revealed that oxygen vacancies preferentially form in the [Ln-O] layer, with their formation energy being significantly influenced by the electronic structure of the A-site cation. Notably, PrBaFe2O5+delta (PBF) exhibits the most favorable electronic structure and a lower oxygen vacancy formation energy. The single cell employing the PBF cathode delivered the highest power output, reaching a peak power density (PPD) of 0.733 W cm(-2) at 750 degrees C with an extremely low polarization resistance (R-p) of 0.080 Omega cm(2), while also exhibiting excellent long-term operational stability. This work elucidates the pivotal role of A-site cation doping in optimizing the bulk transport properties and interfacial characteristics of perovskite cathodes, providing a significant theoretical and experimental foundation for the rational design of high-performance SOFC cathodes.

To overcome the limitations of conventional ionic liquid-based CO2 absorbents-namely high regeneration energy consumption and low absorption capacity-a novel biphasic dual-functionalized ionic liquid system, [AEPH][Im]/NPA/H2O, was synthesized and evaluated. Initially homogeneous, the system undergoes spontaneous phase separation upon CO2 absorption, forming distinct lean and rich phases. At saturation, the rich phase accounted for 53.00% of the total volume, with a viscosity of 15.75 mPa center dot s and a CO2 loading capacity of 3.43 mol center dot L- 1. The system exhibited a high regeneration efficiency of 83.42% at 393.15 K, and the regenerated phases could be recombined into a uniform solution. After six absorption-desorption cycles, the absorbent retained 96.39% of its initial capacity, with only a 1.32% decline in desorption efficiency. The 13C NMR analysis and DFT calculations revealed that CO2 primarily reacts with [AEPH][Im] to form carbamate, carbonate, and bicarbonate species, which are predominantly concentrated in the rich phase, while only unreacted components remain in the lean phase. NPA facilitates the formation of alkyl carbonates via reaction with carbamates, and the high concentration of bicarbonate significantly enhanced desorption efficiency. The total regeneration energy consumption was calculated to be as low as 1.58 GJ center dot t- 1 CO2-markedly lower than that of traditional MEA-based solvents. The [AEPH][Im]/NPA/H2O biphasic system demonstrates superior cyclic stability, high CO2 capture capacity, and low energy demand, presenting a promising alternative for industrial-scale carbon capture applications.

This study reports a synchronized indoor–outdoor field campaign of atmospheric microplastics (MPs) in the coastal urban setting of Dalian, China. Eight synchronized samples were collected using active total suspended particles samplers. Nile Red fluorescence microscopy was used for screening, and 14.6% of the detected particles were verified using micro-Raman spectroscopy. Airborne microplastic concentrations were 4.17–35.28 n m ^−3 indoors and 5.83–45.28 n m ^−3 outdoors, with a bulk indoor-to-outdoor (I/O) ratio of 0.82 ± 1.07. Under a sensitivity-test configuration (excluding an episodic peak on May 8), the mean outdoor and indoor concentrations were 10.37 ± 6.25 n m ^−3 and 9.07 ± 6.25 n m ^−3 , respectively, yielding an I/O ratio of 0.88 ± 0.80. Morphologically, fragments predominated in both environments. Polymer identification revealed a traffic-dominated signature mixed with residential activities, characterized by a dominance of rubber particles alongside polyethylene terephthalate (PET, 19.09%), polyurethane (PU, 4.55%), polyacrylonitrile (PAN, 3.64%), and cotton (3.64%). The results show that the closed building envelope reduced microplastic loading by 12%–18%, demonstrating a physical attenuation effect. Furthermore, size-resolved analysis revealed size-selective infiltration, with smaller MPs (<20 μ m) exhibiting higher cross-barrier permeability. Rather than attempting to establish generalized standard, this pilot study offering preliminary empirical insights into microplastic fate in the built environment, highlighting infiltration dynamics in exposure models and forming a baseline for future multi-season, multi-typology research.

Transition-metal single-atom catalysts based on M-N-C motifs (M = Fe, Ni, Co) are promising electrocatalysts for the CO2 reduction reaction (CO2RR) because of their well-defined active sites, high metal utilization, and tunable electronic structures. In particular, Ni-N-4 sites with axial ligands have recently shown markedly enhanced activity and selectivity by modifying the electronic environment of the Ni center. However, the microscopic role of axial halogen coordination in Ni-based single-atom catalysts remains poorly understood. Herein, we employ density functional theory (DFT) calculations to elucidate how halogen ligands (F, Cl, Br, and I) modulate the electronic structure of Ni-N-4-C and thereby govern its CO2RR performance. We reveal that (i) the ligand electronegativity systematically shifts the Ni 3d energy levels and thus regulates CO2 adsorption; (ii) halogen-induced electron transfer precisely tunes the binding strength of the key *COOH intermediate, following the trend F > Cl > Br > I; and (iii) among the series, the NiN4-F catalyst exhibits the lowest limiting potential and the highest predicted selectivity for CO formation over the competing hydrogen evolution reaction. This work clarifies the atomic-scale mechanism of halogen coordination and establishes a quantitative design principle linking coordination chemistry, electronic structure, and catalytic performance, providing a theoretical basis for high-throughput screening and rational design of high-performance CO2RR electrocatalysts.

Solid oxide fuel cells (SOFCs) offer great promise for clean and efficient energy conversion. However, their widespread commercialization is hindered by limited electrochemical performance, particularly at intermediateto-low operating temperatures. In this study, a high-entropy doping strategy was employed at the A-site of cobalt-free PrBaFe2O5+s (PBF) to develop a novel cathode series, (LaPrNdSmGd)xBa2-xFe2O5+s ((LPNSG)xB2-xF, x = 0.50, 0.75, 1.00, 1.25, 1.50). Among these, (LaPrNdSmGd)1.00Ba1.00Fe2O5+s ((LPNSG)1.00B1.00F) exhibited the best performance. When integrated into anode-supported proton-conducting SOFCs, this cathode delivered a peak power density (PPD) of 1.200 W cm- 2 at 750 degrees C (63.7 % higher than PBF's 0.733 W cm- 2) with an ultra-low polarization resistance (Rp) of 0.046 S2 cm2 (42.5 % reduction from PBF's 0.080 S2 cm2). Long-term stability testing demonstrated a steady voltage of 0.95 V after 50 h at 700 degrees C under constant-current operation. The enhanced performance is attributed to entropy-induced lattice distortion, optimized oxygen-ion transport pathways, and increased oxygen vacancy concentration. These results highlight the substantial application potential of (LPNSG)1.00B1.00F as a high-performance cobalt-free cathode, and underscore the promise of highentropy perovskite oxides (HEPOs) in advancing intermediate-temperature SOFCs technologies.

To achieve superior regeneration properties of the CO2-rich phase without additional auxiliary measures in biphasic CO2 absorbents (e.g., N2 purging or co-activators), a dual-functionalized ionic liquid biphasic solvent of N-Aminoethylpiperazine-Lysine/N-Propanol/water ([AEPH][Lys]/NPA/H2O) was designed for CO2 capture. It demonstrates a remarkable CO2 loading of 1.847 mol center dot mol- 1, while the rich volume being only 53.0 % of the total absorbent and the viscosity as low as 6.10 mPa center dot s. Remarkably, 87.26 % regeneration efficiency was achieved under 393.15 K for 40 min without additives, and the regenerated lower phase could homogeneously recombine with the upper phase. After 10 cycles, regeneration efficiency remained at 84.67 %, while energy consumption was only 1.90 GJ center dot ton-1 CO2 (49.87 % lower than MEA). 13C NMR revealed that bicarbonate/carbonate dominated the CO2 products, as well as some carbamates and a small amount of propyl carbonates. The reaction pathways of bicarbonates/carbonate based on quantum chemical calculations were indicated that through base-catalyzed hydration of tertiary amines on AEPH+ cations, hydrolysis of carbamates and the reaction of water with CO2. The bicarbonate/carbonate exhibits lower thermal stability than carbamates, facilitating efficient regeneration. Based on MPI index, solvation-free energy and weak intermolecular interactions analysis, the solubility of CO2 products in water is higher than NPA. This absorbent demonstrates significant potential for industrial CO2 capture applications.

Optimizing the coordination environment of metal centers in M-N4 complexes is critical for accelerating the reaction kinetics in electrochemical CO2 reduction (CO2RR). Herein, we report a facile strategy for regulating the atomic coordination microenvironment on nickel single-atom catalysts (Ni SACs) by in situ template replacement during synthesis. By implementing one-pot pyrolysis with dynamically sacrificial template replacement, Ni SACs with axial oxygen coordination at Ni-N4 sites, anchored on a N, O-co-doped carbon nanosheet framework (Ni-N4O-C) were successfully obtained. The optimized catalyst exhibits outstanding performance in the electrochemical conversion of CO2 to CO, achieving a maximum Faraday efficiency of 95% within a wide potential window of -0.54 to -1.04 V (vs RHE). Notably, it maintains remarkable durability, retaining over 90% efficiency even after prolonged operation at -0.74 V for 90 h. Further mechanistic studies reveal that the oxygen coordination Ni-N4O-C site by regulating the coordination microenvironment reduces the free energy barrier for key *COOH intermediates compared to conventional Ni-N4 sites. Our findings establish a template-mediated coordination environment adjustment method for the SACs design.

Composite solid electrolytes (CSEs) are promising alternatives to liquid electrolytes in lithium-ion batteries (LIBs). CSEs offer superior electrochemical stability, safety, and mechanical integrity. Herein, a flexible CSE film comprising aluminium-doped Li6.28La3Zr2Al0.24O12 (LLZO-Al) and poly (vinylidene fluoride-cohexafluoropropylene) (PVDF-HFP) is successfully fabricated via an optimised sol-gel synthesis and solution casting method. The LLZO-Al filler, with high cubic-phase purity, effectively reduces the crystallinity of the PVDF-HFP matrix, creating continuous Li+ transport pathways. The optimised composite membrane containing 15 wt% LLZO-Al (CE15 %) exhibits a high room-temperature ionic conductivity of 6.1 x 10-4 S cm-1 and a broad electrochemical stability window up to 4.8 V vs. Li/Li+. Additionally, it demonstrates excellent mechanical flexibility (elongation at break: 162 %) and enhanced thermal resistance. The Li/CE15 %/Li symmetric cell maintains stable cycling for over 2000 h at 0.1 mA cm- 2, confirming outstanding interfacial stability. Furthermore, the LFP/CE15 %/Li full cell delivers an initial discharge capacity of 166.1 mAh g-1 at 0.1 C and retains 86 % of its capacity after 300 cycles. These results highlight the great potential of LLZO-Al/PVDF-HFP/LiTFSI composite electrolytes for high-performance solid-state Li-ion batteries.

A profound understanding of the complex coupling between electrochemical reactions and physical transport processes in the solid oxide fuel cell (SOFC) remains lacking, which restricts effective optimization, control, and diagnostics of SOFC performance. Existing models often overlook or inadequately capture these intertwined processes, impeding accurate analysis of cell behavior under practical operating conditions. In this study, a surface process-based polarization model is developed to comprehensively analyze and identify the fundamental processes occurring within the cell. The model incorporates charge transfer reactions, surface adsorption and diffusion, gas diffusion, and the gas concentration at the surface of the porous electrode. Validation against experimental measurements under diverse operational conditions and working voltages demonstrates the ability of the model to accurately reproduce polarization curves and polarization resistances. Detailed analysis reveals that the polarization resistance components correspond to distinctive underlying processes: R1 (104-105 Hz) corresponds to the high-frequency interfacial resistance. R2 (103-104 Hz) corresponds to the anodic charge transfer reactions. R3 (102-103 Hz) corresponds to the highly overlapping anodic and cathodic processes. And R4 (100-102 Hz) corresponds to mass transport of gases and surface adsorbates within the porous electrode, with temperature exerting an indirect influence through gas diffusion characteristics. This model thus provides a robust tool for unraveling the interplay between electrochemical and physicochemical processes in the cell, offering valuable insights to guide their control, diagnostics, and performance optimization.

Thermal annealing is a conventional method used to eliminate residual solvents in perovskite films, reducing internal and interfacial defects. However, due to the high saturation vapor pressure of the residual solvent dimethyl sulfoxide, it is difficult to quickly remove the residual solvent at low temperatures. In this paper, the high permeability and diffusion of supercritical CO2 (ScCO2) were used to quickly remove the residual solvent of film at low temperatures. The effects of ScCO2 annealing on the surface morphology, residual solvents, internal and interfacial defects of perovskite thin films were investigated. The experimental results indicate that ScCO2 annealing significantly improves the removal efficiency of residual solvents compared to low-temperature annealing, effectively minimizing internal and interfacial defects. Additionally, the interaction energy of CO2 with the perovskite crystal plane reduces the surface energy of the crystal, resulting in a significant increase in the average grain size of the crystal by about 91.2%. Notably, the average crystal size of the film prepared by chlorobenzene as an antisolvent increased from 209.35 nm to 704.57 nm. The high penetration of ScCO2 also promoted uniform crystal growth, thereby reducing crystal structure deformation and defects. The carrier lifetime of perovskite thin films after ScCO2 annealing increased by over 58.8% on average.

Polyphenylene oxide (PPO)/cellulose nanocrystal (CNC)/carbon black (CB) microcapsules were fabricated by the supercritical extraction of Pickering emulsion (SFEPE) method. The effects of Pickering emulsion formulations on the emulsion properties, emulsification kinetics, and CPM properties were investigated. The phase behaviors in the supercritical extraction process were studied, and the mass transfer between the emulsion droplet and supercritical carbon dioxide (SCCO2) was also interpreted. The results indicate that CNC concentration, CB concentration, and NaCl concentration can decrease the droplet size and creaming index of emulsions, while the water–oil ratio can decrease the droplet size but enhance the creaming index. The emulsion formulations of water–oil > 3, CNC concentration > 0.25 mg/mL, CB concentration < 2.5 mg/mL, and NaCl concentration > 2.5 mg/mL are conducive to the emulsion formation and emulsification kinetics. For the supercritical extraction on Pickering emulsions, the operation conditions slightly above the mixture critical point (9 MPa at 313 K, for example) are proved to be conducive to the extraction.

The refrigeration efficiency is mainly dependent on the low temperature generated by gas wave dynamics in oscillation channel. In this paper, a temperature rapid monitoring method for short light path based on the calibration-free wavelength modulation spectroscopy-tunable diode laser absorption spectroscopy (WMS-TDLAS) method is proposed. The selection of absorption wavelength, measurement procedure and data processing are specifically introduced. The wave dynamics and medium temperature under different pressure ratios and rotary speeds are studied, and the energy transfer efficiency of the gas wave refrigerator is evaluated. As the pressure ratio increases, the temperature in the cold zone behind the expansion wave gradually decreases to 257.6 K and the relative humidity of the cold zone inside the channel increases, which is caused by local condensation. At the same time, the expansion refrigeration efficiency is increasing from 27.3 % to 64.9 %. The increasing rotary speed of rotor also benefit to refrigeration efficiency from 45.8 % to 75.6 % as low temperature decreases to 252.1 K, which illustrates that rotary speed has more improvement effect on refrigeration efficiency than just higher-pressure ratio.

The gradual degradation of the electrical properties of solid oxide fuel cells (SOFC) when operating on C-containing fuels poses a significant obstacle to their widespread implementation in industry. This paper investigates the distribution of carbon deposition and its structural evolution in the traditional SOFC electrode (Ni/YSZ). The carbon deposition weight in direct methane SOFC increases linearly with exposure times without electrochemical reactions. The carbon initially deposits at the triple-phase boundary (TPB) of the anode, subsequently covering the surface of Ni particles and eventually accumulating to form a carbon deposit layer. Three methods for alleviating carbon deposition are compared. The polarization current could inhibit the carbon deposition but the high stress within the cell had resulted in the brittleness of the electrode, as well as significant coking in the central region of the anode after 26 h. Alternating changes in methane and hydrogen can significantly reduce the degradation rate of the cell. The reasonable gas switching frequency is from 60 min to 120 min. After high electrolytic current, the gap between the anode and the electrolyte can be achieved at 68.2 mu m.

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The theoretical voltage of lithium nickel phosphate (LNP) is as high as 5.1 V, making it well-suited to meet the demand for high voltage and high capacity required by today’s electric devices. However, the application of electrode material in the power battery technology field is limited in achieving a high actual discharge ratio, high ionic conductivity, and sufficient cycling performance challenges. Therefore, this study is mainly calculated through the first principle, utilizing the solvothermal method for synthesis, and the correlation between iron ions doped modification and LNP performance. The Castep module of Material Studio calculates the performance of ionic conductivity, binding energy, and lithium intercalation potential. In addition, the electrochemical characteristics of LNP and iron-doped LNP (LFNP) are also evaluated using experiments and calculation methods. The study successfully combines theoretical calculations with solvothermal synthesis results to reveal that incorporating Fe in LNP lowers the valence state of Ni, thereby stabilizing the lattice and broadening the lithium-ion diffusion channel. Therefore, this modification greatly improves electrochemical performance, especially cycle stability. Specifically, the discharge capacity at 0.1 C is increased by 131

The crystal quality of the perovskite thin film directly influences the conversion efficiency of the cell, serving as the absorption layer of perovskite solar cells. Different annealing methods can present remarkable impacts on the quality of perovskite films. Conventional low-temperature thermal annealing makes it difficult to quickly and thoroughly remove the residual solvent inside the film. In this study, the supercritical carbon dioxide (ScCO2) annealing method was demonstrated to achieve low-temperature annealing upon perovskite thin film. ScCO2 can penetrate the inside of the film to accelerate the diffusion of residual solvent molecules. The surface morphology, crystallinity, crystal deformation, and internal solvent residue of six films prepared by different methods were studied, focusing on the effects of solvent diffusion rate on crystal quality in ScCO2 and conventional annealing. The results show that ScCO2 can enhance the solvent diffusion ability at low temperatures. The thin film crystals formed by ScCO2 annealing have less deformation than conventional high-temperature annealing, which can reduce the interface defects caused by conventional low-temperature annealing and avoid solvent residue.