Support Layer Research Articles

Preparation of thin-film nanocomposite membrane with the addition of cysteine-modified MoS2 to enhance nanofiltration performance

Novel thin-film nanocomposite nanofiltration ((TFN)-NF) membrane was successfully fabricated by adding MoS2 functionalized with cysteine in a polysulfone (PSf) layer and the active layer to enhance separation performance in water and alcohol. A novel TFN-NF membrane was prepared through interfacial polymerization (IP), which reacts with an aqueous DETA solution containing MoS2-cys and a TMC organic solution onto the PSF/MoS2-cys support layer. A PSf support layer was incorporated with MoS2-cys, which enhanced the membrane permeability due to increasing porosity and hydrophilicity. Furthermore, MoS2 is essential in forming thin films and Turing structures of the NF membrane, resulting in enhanced permeability for water and alcohol. The prepared TFN-NF membrane has shown a notable permeability of 7.9 LMH/bar and a rejection rate of 99% for MgSO4. It also demonstrated excellent fouling resistance after three chemical cleaning cycles and long-term running. The TFN-NF membrane with MoS2 showed improved permeability for water and alcohol solvents, such as methanol and ethanol, of 5.5, 1.2, and 0.48 LMH/bar, respectively. This work would present a valuable strategy for preparing a TFN-NF membrane to retrieve alcohol solvents.

High permeability Performance TFC Nanofiltration Membrane with Two dimensional Nanochannels Support Layer Fabricated by Dissolving of Nanosheets

A synthesized thin film composite (TFC) nanofiltration membrane was prepared by incorporating Mg(OH)2 nanosheets at different ratios (from 0 to 0.5 wt%) into polysulfone (PSf) support layer. The polypiperazinamide (PPA) layer was prepared on the polysulfone support layer by means of interfacial polymerization. Then TFC membrane was then etched with H2SO4 and a PPA selective layer was established using trimesoyl chloride (TMC) and piperazine (PIP). The characterization results show that the modifications of the PSf substrate with Mg(OH)2 alter the physicochemical properties of the poly(piperazine amide) selective layer. Through the introduction of Mg(OH)2, the hydrophilicity of the TFC membrane was increased (WCA: 20.5°), promoting more linear polypiperinamide. The addition of 0.4 wt% Mg(OH)₂ to the PSf substrate, followed by sulfuric acid etching, resulted in a 196 % increase in membrane flux and with Na₂SO₄ retention at 97.72 %. The change in matrix composition favoured the generation of a lighter and rougher selective layer. The two-dimensional nanochannels in the support layer provided additional channels for water molecule transport. The membrane with two-dimensional nanochannels exhibited excellent resistance to contamination, with a flux recovery of 92.8 % for bovine serum albumin (BSA).

Adsorption of steroid hormone micropollutant by polyethersulfone ultrafiltration membranes with varying morphology

The effective removal of micropollutants necessitates the use of dense membranes, such as thin-film composite (TFC) reverse osmosis (RO) and nanofiltration (NF) membranes. TFCs have a polyamide active layer interfacially polymerized on a support layer that is typically made of polysulfone (PSu) or polyethersulfone (PES). Retention by NF and RO is often incomplete because micropollutants are adsorbed to the polymer material and subsequently permeate via a combination of convection and diffusion, which evidences a breakthrough curve. When describing breakthrough phenomena, the role of the support membrane is commonly neglected, even though the adsorption in this layer can be significant. This work investigated the adsorption of steroid hormone micropollutants (17β-estradiol, E2) by fabricated and commercial PES ultrafiltration membranes with varying morphology.By increasing the coagulation bath temperature between 10 and 70 °C, the pure water permeability increased from 13 to 3800 L/m2·h−1·bar−1, and consequently, the average pore size rose from 12 to 191 nm. The fabricated membranes with smaller pore sizes showed higher E2 removal via adsorption which can be attributed to the higher internal surface area. The adsorbed mass of fabricated PES membranes (using dimethylformamide (coded as PDG) and N-methyl-2-pyrrolidone (coded as PNG) and PES (Istanbul Technical University (ITU), with non-woven supports) varies from 0.30 to 0.60, 0.27–0.60 and 1–1.2 ng·cm−2, respectively. These values are lower than the adsorbed masses with commercial Biomax (Millipore Inc.) membranes (0.5–2.0 ng·cm−2). Ultrafiltration membranes used as support for composite membranes, nanofiltration or as filters in sample preparation benefit from lower micropollutant adsorption.

Development of large-scale laminar-structure nanofiltration membranes for high dye rejection and enhanced robustness: Utilizing potassium ion-crosslinked graphene oxide and polyethyleneimine surface coating

Laminar graphene oxide (GO) membranes are at the forefront of groundbreaking research as a prospective advanced solution for nanofiltration. Both physical and computational experiments have showcased the exceptional efficacy of these GO membranes. However, scalability and robustness issues still remain significant hurdles for the practical implementation of GO membranes. In this study, to address these issues concurrently, we employed tape-casting of GO hydrogel induced by potassium ion crosslinking alongside polyethyleneimine crosslinking between the tape-casted laminar GO layers and the porous support layer. Through this approach, we successfully crafted a scalable laminar GO membrane encompassing an area of 900 cm², characterized by good uniformity. The GO membranes achieved excellent rejection efficiencies of 99.22 %, 99.42 %, and 99.27 % for methylene blue, methyl orange, and rhodamine B, respectively, with 0.77 LMH/bar of pure water permeability. Furthermore, the GO membranes demonstrated enhanced stability, validated by both long-term operation and testing under harsh conditions.

PA/APVC nanofiltration membrane from reactive positively charged substrate membrane

Efficient Li+ and Mg2+ from natural seawater and salt lakes using nanofiltration is essential for efficient extraction of lithium resources and to address the global energy shortage. The combination of size sieving and the Donnan effect is crucial for optimal selectivity. We proposed a positively charged reactive support layer to design dual positively charged layer to enhance the magnesium-lithium separation. The positively charged support layer was prepared by ammoniating the PVC membrane with PEI, and then reacted with TMC to successfully prepare a dual positively charged layer PA/APVC nanofiltration membrane with high Li+/Mg2+ selectivity. The reactive support layer not only established a covalent bond connection with the PA layer, which increased the stability of the active layer, but also showed a positive charge (23.59 mV at pH=7) after ammonization, which further enhanced the Mg2+ repulsion from 82.57 % to 98.56 %. Furthermore, the highest separation factor achieved was 23.34 when a mixed solution containing Mg2+ and Li+ in a mass ratio of 50:1 was utilized, which was 13.48 times that of commercial nanofiltration membranes. The utilization of a reactive substrate membrane in the fabrication process of the PA/APVC membrane offers innovative prospects for future investigations on magnesium-lithium separation, contributing to the advancement of nanofiltration membranes.

Effect of Si substrate conductivity on surface acoustic wave resonator

A surface acoustic wave (SAW) filter’s bandwidth and quality are determined by its resonators’ electromechanical coupling coefficient (k2) and impedance ratio (IR). Research commonly focuses on the effects of piezoelectric material and cutting direction on these parameters. This paper investigates the effect of the conductivity of the Si substrate on k2 and IR through finite element method (FEM) simulations. A new model based on the modified Butterworth-van-Dyke (MBVD) model is presented. This new model takes into account the substrate parasitic capacitance and resistance to predict resonator performance on low resistivity (LR) Si piezoelectric on insulator (POI) substrates. Both high resistivity (HR) Si and LR-Si are utilized to fabricate POI SAW resonators, which are subsequently tested. The high conductivity of the Si support layer leads to a decrease in both k2 and IR. By employing Si substrates with different resistances during fabrication, it becomes possible to manufacture resonators with varying k2 values, thus meeting diverse bandwidth requirements for filters.

A high-performance TFN membrane prepared by a novel PE support layer, a polydopamine interlayer, and a doped MoS2 quantum dots@ZnO nanocomposites-incorporated polyamide active layer

Herein, thin film nanocomposite (TFN) membranes were prepared with excellent chemical stability and separation performance for organic solvent nanofiltration (OSN) applications. The support membrane was synthesized via a new approach, in which a blend of two immiscible polymers, i.e. high density polyethylene (HDPE)-polystyrene (PS), which were compatibilized with styrene-ethylene-butylene-styrene (SEBS), was prepared through mixing by a Brabender, followed by fabricating blend sheets through a hot press machine. The PE support was then prepared by extracting the PS/compatibilizer phase from the blend sheet. The hydrophilicity of the PE support membrane was considerably enhanced with a polydopamine (PDA) layer. Different nanoparticles including nanoflower (NF) ZnO, nanosphere (NS) ZnO, MoS2 Quantum dots-nanoflower ZnO nanocomposite (QDs@NF ZnO), and MoS2 Quantum dots-nanosphere ZnO nanocomposite (QDs@NS ZnO) were incorporated into the polyamide (PA) active layer of the membranes to enhance the performance of the TFN membranes. The separation performance of the TFN membranes was investigated for rejecting different dyes dissolved in methanol. Our results demonstrate outstanding separation performance, with a dye rejection of 99.6 %, 99.6 %, 99.8 %, and 99.9 % for methylene blue, crystal violet, rhodamine B, and methyl green, respectively. Additionally, the TFN membranes incorporated with QDs@NF ZnO nanoparticles showed great solvent resistance, with a methanol permeance up to 6.7 L/m2.h.bar after activation with dimethylformamide.

Quantitative analyzing the effect of pore distribution on formation of active layer for forward osmosis membrane

The morphology and performance of polyamide active layer can be controlled by the pore size and surface porosity of support layer. Nevertheless, further investigation is required to elucidate the impact of pore distribution and the specific role of each pore. Therefore, by introducing polyetherimide (PEI) as a sacrificial top layer, the support layer with a wide pore distribution was prepared by co-casting method. A mathematical model was developed to enable the estimation of the impact of each pore radius and pore distribution on the structure and performance of the active layer. During interfacial polymerization process, the surface pore size and distribution of the support layer influenced the incipient film which consists of the polyamide colloids and dominates the successive growth of polyamide layer. It was suggested that both average pore radius and pore distribution contributed to the composite of incipient film. The overall η of 1.77 for S75 corresponded to an incipient film composed of linear polyamide terminated with MPD and fully cross-linked polyamide, resulting in the best performing membrane (C75) with DC of 0.75 and structural parameter as low as 230 μm. A comparison of C75 with C0 revealed an increase in water flux of 138 % and a minor increase in salt flux of 6.37 %. This work presents a novel approach to enhancing the performance of FO membranes and offers a new perspective on the structure-effect relationship.

Viability of Total Ammoniacal Nitrogen Recovery Using a Polymeric Thin-Film Composite Forward Osmosis Membrane: Determination of Ammonia Permeability Coefficient.

Total ammoniacal nitrogen (TAN) occurs in various wastewaters and its recovery is vital for environmental reasons. Forward osmosis (FO), an energy-efficient technology, extracts water from a feed solution (FS) and into a draw solution (DS). Asymmetric FO membranes consist of an active layer and a support layer, leading to internal concentration polarization (ICP). In this study, we assessed TAN recovery using a polymeric thin-film composite FO membrane by determining the permeability coefficients of NH4+ and NH3. Calculations employed the solution-diffusion model, Nernst-Planck equation, and film theory, applying the acid-base equilibrium for bulk concentration corrections. Initially, model parameters were estimated using sodium salt solutions as the DS and deionized water as the FS. The NH4+ permeability coefficient was 0.45 µm/s for NH4Cl and 0.013 µm/s for (NH4)2SO4 at pH < 7. Meanwhile, the NH3 permeability coefficient was 6.18 µm/s at pH > 9 for both ammonium salts. Polymeric FO membranes can simultaneously recover ammonia and water, achieving 15% and 35% recovery at pH 11.5, respectively.

Customizable Fabrication of Photothermal Microneedles with Plasmonic Nanoparticles Using Low-Cost Stereolithography Three-Dimensional Printing.

Photothermal microneedle (MN) arrays have the potential to improve the treatment of various skin conditions such as bacterial skin infections. However, the fabrication of photothermal MN arrays relies on time-consuming and potentially expensive microfabrication and molding techniques, which limits their size and translation to clinical application. Furthermore, the traditional mold-and-casting method is often limited in terms of the size customizability of the photothermal array. To overcome these challenges, we fabricated photothermal MN arrays directly via 3D-printing using plasmonic Ag/SiO2 (2 wt % SiO2) nanoaggregates dispersed in ultraviolet photocurable resin on a commercial low-cost liquid crystal display stereolithography printer. We successfully printed MN arrays in a single print with a translucent, nanoparticle-free support layer and photothermal MNs incorporating plasmonic nanoaggregates in a selective fashion. The photothermal MN arrays showed sufficient mechanical strength and heating efficiency to increase the intradermal temperature to clinically relevant temperatures. Finally, we explored the potential of photothermal MN arrays to improve antibacterial therapy by killing two bacterial species commonly found in skin infections. To the best of our knowledge, this is the first time describing the printing of photothermal MNs in a single step. The process introduced here allows for the translatable fabrication of photothermal MN arrays with customizable dimensions that can be applied to the treatment of various skin conditions such as bacterial infections.

Investigation of a novel bilayered PCL/PVA electrospun nanofiber incorporated Chitosan-LL37 and Chitosan-VEGF nanoparticles as an advanced antibacterial cell growth-promoting wound dressing

Chronic wounds have become a growing concern as they can have a profound impact on individuals, potentially resulting in mortality. It is crucial to prevent and manage bacterial infections, particularly drug-resistant ones. Antimicrobial peptides, such as LL-37, can firmly eliminate pathogens. Additionally, the process of angiogenesis, facilitated by growth factors like VEGF, is essential for tissue repair and wound healing. To enhance the stability and bioavailability of therapeutic agents, targeted delivery strategies utilizing Chitosan-based carriers have been employed. Electrospun biopolymers in advanced wound dressings have revolutionized wound care by providing a more effective and efficient solution for promoting tissue regeneration and speeding up the healing process. The present investigation utilized Chitosan nanoparticles to encapsulate the recombinant LL37 peptide and VEGF. An in-depth investigation was carried out to analyze the biophysical and morphological traits of the LL37-CSNPs and VEGF-CSNPs. The first support layer consisted of PCL electrospun nanofiber, followed by the electrospinning of PVA/CsLL37, PVA/CsVEGF, and PVA/CsLL37/CsVEGF onto the PCL layer. An in vitro examination assessed the fabricated nanofibers’ morphological, mechanical, and biological characteristics. The antimicrobial effects were tested on methicillin-resistant Staphylococcus aureus (MRSA). The in vivo experiments assessed the antibacterial and wound-healing capabilities of the nanofibers. The findings validated the continuous release of LL37 and VEGF. The composite material PCL/PVA/CsLL37/CsVEGF demonstrated potent bactericidal and antioxidant characteristics. The cytotoxic assay demonstrated the biocompatibility of the fabricated nano mats and their potential to accelerate fibroblast cell proliferation. The efficacy of PVA/CsLL37/CsVEGF in promoting wound healing was confirmed through an in vivo wound healing assay. Furthermore, the histological analysis provided evidence of faster epidermal formation and improved antibacterial activity in wounds covered with PVA/CsLL37/CsVEGF. Adding LL37 and VEGF to the composite material improves the immune response and promotes blood vessel formation, accelerating wound healing and decreasing inflammation.

Design and preparation of woven fabric-reinforced substrate: A new pathway for robust thin film composite membrane

The thin film composite (TFC) membrane possesses the highest commercial application potential among all types of forward osmosis (FO) membranes. The support layer of the membrane plays a crucial role in both bearing mechanical loads and facilitating the active layer formation. Herein, we addressed the issues of low permeability and poor mechanical strength of the conventional TFC FO membrane by selecting suitable fabrics and optimizing membrane design and preparation. Polyester (PS) woven fabric, with its high strength, low thickness, and high porosity, served as an excellent material for reinforcing the strength of the FO membrane. We employed a novel double-blade casting method to address the defect issue associated with the conventional single-blade casting method. The influencing factors and quality control strategies of the fabric-reinforced substrate were systematically investigated. Furthermore, membrane characterization techniques, including scanning electron microscopy (SEM), liquid-liquid displacement porometer, and cross-flow FO system, were used to reveal the influences of different substrates, including polysulfone (PSU), polyacrylonitrile (PAN), and polyetherimide (PEI), on the structure and performance of the fabric-reinforced TFC-FO membrane. Compared to commercial FO membranes, the TFC/PSU membrane exhibited superior FO performance, with a water flux of 24.1 LMH, and outstanding mechanical strength that was more than 10-times higher than that of free-standing membranes. This study demonstrates a new pathway for engineering robust TFC-FO membranes with low structural parameters as well as excellent scalability of the membrane fabrication method.

3D bioprinting of dense cellular structures within hydrogels with spatially controlled heterogeneity

Embedded bioprinting is an emerging technology for precise deposition of cell-laden or cell-only bioinks to construct tissue like structures. Bioink is extruded or transferred into a yield stress hydrogel or a microgel support bath allowing print needle motion during printing and providing temporal support for the printed construct. Although this technology has enabled creation of complex tissue structures, it remains a challenge to develop a support bath with user-defined extracellular mimetic cues and their spatial and temporal control. This is crucial to mimic the dynamic nature of the native tissue to better regenerate tissues and organs. To address this, we present a bioprinting approach involving printing of a photocurable viscous support layer and bioprinting of a cell-only or cell-laden bioink within this viscous layer followed by brief exposure to light to partially crosslink the support layer. This approach does not require shear thinning behavior and is suitable for a wide range of photocurable hydrogels to be used as a support. It enables multi-material printing to spatially control support hydrogel heterogeneity including temporal delivery of bioactive cues (e.g. growth factors), and precise patterning of dense multi-cellular structures within these hydrogel supports. Here, dense stem cell aggregates are printed within methacrylated hyaluronic acid-based hydrogels with patterned heterogeneity to spatially modulate human mesenchymal stem cell osteogenesis. This study has significant impactions on creating tissue interfaces (e.g. osteochondral tissue) in which spatial control of extracellular matrix properties for patterned stem cell differentiation is crucial.

Modeling Ion Transport across Thin-Film Composite Membranes During Saltwater Electrolysis.

Affordable thin-film composite (TFC) membranes are a potential alternative to more expensive ion exchange membranes in saltwater electrolyzers used for hydrogen gas production. We used a solution-friction transport model to study how the induced potential gradient controls ion transport across the polyamide (PA) active layer and support layers of TFC membranes during electrolysis. The set of parameters was simplified by assigning the same size-related partition and friction coefficients for all salt ions through the membrane active layer. The model was fit to experimental ion transport data from saltwater electrolysis with 600 mM electrolytes at a current density of 10 mA cm-2. When the electrolyte concentration and current density were increased, the transport of major charge carriers was successfully predicted by the model. Ion transport calculated using the model only minimally changed when the negative active layer charge density was varied from 0 to 600 mM, indicating active layer charge was not largely responsible for controlling ion crossover during electrolysis. Based on model simulations, a sharp pH gradient was predicted to occur within the supporting layer of the membrane. These results can help guide membrane design and operation conditions in water electrolyzers using TFC membranes.

Nanoimprint Lithography for Next-Generation Carbon Nanotube-Based Devices.

This research reports the development of 3D carbon nanostructures that can provide unique capabilities for manufacturing carbon nanotube (CNT) electronic components, electrochemical probes, biosensors, and tissue scaffolds. The shaped CNT arrays were grown on patterned catalytic substrate by chemical vapor deposition (CVD) method. The new fabrication process for catalyst patterning based on combination of nanoimprint lithography (NIL), magnetron sputtering, and reactive etching techniques was studied. The optimal process parameters for each technique were evaluated. The catalyst was made by deposition of Fe and Co nanoparticles over an alumina support layer on a Si/SiO2 substrate. The metal particles were deposited using direct current (DC) magnetron sputtering technique, with a particle ranging from 6 nm to 12 nm and density from 70 to 1000 particles/micron. The Alumina layer was deposited by radio frequency (RF) and reactive pulsed DC sputtering, and the effect of sputtering parameters on surface roughness was studied. The pattern was developed by thermal NIL using Si master-molds with PMMA and NRX1025 polymers as thermal resists. Catalyst patterns of lines, dots, and holes ranging from 70 nm to 500 nm were produced and characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Vertically aligned CNTs were successfully grown on patterned catalyst and their quality was evaluated by SEM and micro-Raman. The results confirm that the new fabrication process has the ability to control the size and shape of CNT arrays with superior quality.

Fabrication of Large-Area Nanostructures Using Cross-Nanoimprint Strategy.

Nanostructures with sufficiently large areas are necessary for the development of practical devices. Current efforts to fabricate large-area nanostructures using step-and-repeat nanoimprint lithography, however, result in either wide seams or low efficiency due to ultraviolet light leakage and the overflow of imprint resin. In this study, we propose an efficient method for large-area nanostructure fabrication using step-and-repeat nanoimprint lithography with a composite mold. The composite mold consists of a quartz support layer, a soft polydimethylsiloxane buffer layer, and multiple intermediate polymer stamps arranged in a cross pattern. The distance between the adjacent stamp pattern areas is equal to the width of the pattern area. This design combines the high imprinting precision of hard molds with the uniform large-area imprinting offered by soft molds. In this experiment, we utilized a composite mold consisting of three sub-molds combined with a cross-nanoimprint strategy to create large-area nanostructures measuring 5 mm × 30 mm on a silicon substrate, with the minimum linewidth of the structure being 100 nm. Compared with traditional step-and-flash nanoimprint lithography, the present method enhances manufacturing efficiency and generates large-area patterns with seam errors only at the micron level. This research could help advance micro-nano optics, flexible electronics, optical communication, and biomedicine studies.

Graphene-Enhanced UV-C LEDs.

Light-emitting diodes in the UV-C spectral range (UV-C LEDs) can potentially replace bulky and toxic mercury lamps in a wide range of applications including sterilization and water purification. Several obstacles still limit the efficiencies of UV-C LEDs. Devices in flip-chip geometry suffer from a huge difference in the work functions between the p-AlGaN and high-reflective Al mirrors, whereas the absence of UV-C transparent current spreading layers limits the development of UV-C LEDs in standard geometry. Here it is demonstrated that transfer-free graphene implemented directly onto the p-AlGaN top layer by a plasma enhanced chemical vapor deposition approach enables highly efficient 275nm UV-C LEDs in both, flip-chip and standard geometry. In flip-chip geometry, the graphene acts as a contact interlayer between the Al-mirror and the p-AlGaN enabling an external quantum efficiency (EQE) of 9.5% and a wall-plug efficiency (WPE) of 5.5% at 8V. Graphene combined with a ≈1nm NiOx support layer allows a turn-on voltage <5V. In standard geometry graphene acts as a current spreading layer on a length scale up to 1mm. These top-emitting devices exhibit a EQE of 2.1% at 8.7V and a WPE of 1.1%.

A Zero-Gap Gas Phase Photoelectrolyzer for CO2 Reduction with Porous Carbon Supported Photocathodes.

A modified Metal-Organic Framework UiO-66-NH2-based photocathode in a zero-gap gas phase photoelectrolyzer was applied for CO2 reduction. Four types of porous carbon fiber layers with different wettability were employed to tailor the local environment of the cathodic surface reactions, optimizing activity and selectivity towards formate, methanol, and ethanol. Results are explained by mass transport through the different type and arrangement of carbon fiber support layers in the photocathodes and the resulting local environment at the UiO-66-NH2 catalyst. The highest energy-to-fuel conversion efficiency of 1.06 % towards hydrocarbons was achieved with the most hydrophobic carbon fiber (H23C2). The results are a step further in understanding how the design and composition of the photoelectrodes in photoelectrochemical electrolyzers can impact the CO2 reduction efficiency and selectivity.

Infrared Gas Sensor Based on MEMS Technology for Gas Detection

Abstract This paper presents an infrared gas sensor based on MEMS technology. The sensor can detect the input, output light intensity, and perform data processing. According to the corresponding results, the concentration of the gas to be measured can be obtained. The thickness of the protective layer and supporting layer of the infrared sensor transmitting unit can be changed. The proper size can make the transmitting unit work in a state of low deformation and high efficiency. The concentration of gas to be measured can be measured indirectly by using the sensor to detect the change of resistance of the unit. In this paper, the thickness of the protective layer and the supporting layer of the sensor transmitting unit is analyzed by finite element analysis. It is found that the thickness has a linear relationship with the deformation and temperature of the bridge deck. Further, it can be seen that when the thickness of the emission layer and the support layer is selected at the appropriate size, it has a good working state. Therefore, the sensor has good infrared emission intensity and stability. It has a broad application prospect in the early fire characteristic gas monitoring of cable.

BaZr0.1Ce0.7Y0.1Yb0.1O3-δ particles embedded PrBa0.5Sr0.5Co1.5Fe0.5O5+δ hollow nanofibers with 3D fast transmission path as oxygen electrode for proton-conducting solid oxide electrolysis cell

To address the challenge of low-temperature catalytic activity of oxygen electrodes, a high-activity triplex ionic conductor material, PrBa0.5Sr0.5Co1.5Fe0.5O5+δ (PBSCF), is prepared using electrospinning. The preparation PBSCF and BaZr0.1Ce0.7Y0.1Yb0.1O3-δ (BZCYYb) nanofibers composite electrodes are used with different composite methods to improve the catalytic activity and the proton transport pathway within the electrode. The results show that PBSCF@BZCYYb prepared by PBSCF and BZCYYb pre-mixed one-step electrospinning has high porosity and 3D interwoven continuous transmission path, exhibiting minimal polarization impedance on symmetric cells. The electrolysis cell with PBSCF@BZCYYb|BZCYYb|NiO-BZCYYb (active layer) |NiO-BZCYYb (support layer) structure shows electrolysis current densities of 775.4 mA cm−2 under 1.3 V at 650 °C with 20%H2O+80%Air atmosphere. Additionally, during the constant voltage electrolysis, the cell shows acceptable stability in 60 h at 650 °C, considered to be a promising oxygen electrode material in this work.