Proton Conductivity Research Articles

Synthesis, structure, and small molecule in situ modification effects on proton conduction properties of triazine‐based triscarboxylic acid complexe

In this study, we synthesized and characterized a new Co(II)‐based coordination polymer, denoted as {[Co(HL)(dpa)]·H2O}n (1), derived from the H3L ligand and dpa co‐ligand. Single crystal X‐ray diffraction revealed that 1 forms a two‐dimensional (2D) layer and a three‐dimensional (3D) supramolecular structure via hydrogen bonding interactions. Presence of carboxylic acid groups in 1 was confirmed by X‐ray crystallography, prompting investigation into its proton transport properties. Additionally, electrostatic potential surface and nucleophilic index analyses were conducted to simulate potential proton transfer pathways. Furthermore, we prepared nine modified encapsulated materials using 1 as the base material (SDA@1, APH@1, APY@1, TA@1, BA@1, DIC@1, IDZ@1, SCA@1, and TYD@1), and tested their proton conductivity and activation energy compared to pure Nafion membrane and 1, analyzing the influence of different small molecule structures on proton conductivity. Comparative analysis revealed that only SDA@1 exhibited enhanced proton conductivity and reduced activation energy at 303 K, with an improvement rate of 220.8%. We hope that the methods presented herein can provide valuable insights for the design and development of high‐performance proton‐conducting materials, as well as for the exploration of proton conduction mechanisms.

The strategy of micropore confinement via organic macrocyclic cavities for designing novel high-performance proton exchange membranes

The high-temperature hydrogen proton exchange membrane fuel cell is considered a disruptive technology for future energy applications. However, the weak binding strength between the proton carriers (phosphoric acid molecules) with polymer chains reduces the operational stability and proton transfer efficiency at conditions of high temperature and low humidity. In this work, a strategy of micropore confinement via organic macrocyclic cavities (sulfonic calix[4]arenes, sulfonic calix[8]arenes, sulfonated β-cyclodextrin) was developed for designing novel mixed matrix membranes functioning as high-temperature hydrogen proton exchange membranes. Benefitting from the confined micropores constructed by supramolecular cavities, the obtained mixed matrix membranes showed a higher uptake and retention capability of phosphoric acid as well as lower membrane swelling, yielding an enhanced proton conductivity. The proton conductivity of the mixed matrix membranes was 2–3 times higher while the conductivity attenuation was only 58.6% comparing with neat PBI membrane, (140℃, relative humidity = 0). In addition, due to the good compatibility caused by hydrogen bonding between fillers and polymer chains, the volume swelling was only 14% and the mechanical strength of the obtained mixed matrix membranes increased. We believe the strategy of micropore confinement via organic macrocyclic cavities for designing the novel mixed matrix membranes is thought to be of great significance for the research on high-temperature proton exchange membrane.

Mechanisms of metabolic regulation and enhanced methane production by hydrolytic nanozyme in sludge anaerobic digestion

Artificial nanozymes have demonstrated potential as natural enzyme substitutes due to their efficient biomacromolecule hydrolysis. However, the metabolic and catalytic mechanisms of nanozyme during the biodegradation of complex organics remain inadequately understood. This study evaluated the effect of the hydrolytic mechanism of cerium-based metal–organic frameworks (Ce-MOFs) hydrolytic nanozyme on shaping microbiome and metabolic functions. Biochemical methane potential test revealed that Ce-MOF-based hydrolytic nanozyme increased methane production by 7.8 − 22.2% as the hydrolytic nanozyme dosage increased from 50 to 150 mg/g VS. The highest methane production observed in 150 mg/g VS dosage of Ce-MOF (Ce-MOF-150) could be attributed to the enhanced sludge hydrolysis, acidogenesis, and methanogenesis processes, proven by the increased relative abundance of dominant acidogens and methanogens. Furthermore, 150 mg/g VS hydrolytic nanozyme bolstered the relative abundance of genes encoding acetyl-CoA carboxylase (accABCD) and involving in glycolysis (hxk and pfkA). These quantities were higher (8.31 − 34.14%) than that without nanozyme addition. The enhanced relative abundance of ackA, pta, cdhCDE, mvhAD, fpoABCDHIJKLMNO, vhoC, rnfABCDEG, mtrABCDEFGH, and hdrABC in the Ce-MOF-150 test indicated that the high proton conductivity of nanozyme facilitated acetoclastic methanogenesis and membrane-bound electron transport system, thereby enhancing methane production. These findings contribute to the expanding understanding of the application of artificial nanozymes as biocatalysts for solid waste resource recovery, providing a promising approach for methane production from sewage sludge.

Tunnel-Structured Phosphate Exhibiting High Proton Conductivity and Thermal Stability over a Wide Intermediate Temperature Range.

For the practical application of fuel cells in vehicles, it is a challenge to develop a proton solid electrolyte that coexhibits thermal stability and high proton conductivity at wide intermediate temperatures. Here, we report on the tunnel structured phosphate KNi1-xH2x(PO3)3·yH2O, which exhibits high proton conductivity at room temperature up to 500 °C, with the conductivity value reaching 1.7 × 10-2 S cm-1 at 275 °C for x = 0.18. This material, composed of the smallest cations that form the tunnel framework with face-shared (KO6) and (NiO6) chains and PO4 tetrahedral chains, retained the rigid framework up to 600 °C. Two oxygen sites of water molecules located adjacent to each other along the PO4 tetrahedral chains in the tunnel provided the proton conduction pathway. The sample maintained a conductivity of 5.0 × 10-3 S cm-1 for 10 h at 150 °C while changing the measurement atmosphere to a N2 gas flow, a 4% H2-96% Ar gas flow, and an O2 gas flow. The conductivity value at x = 0.18 obtained from the DC measurement was in the order of 10-6 S cm-1, close to the instrument's measurement limit. These results demonstrate that tunnel phosphate has potential as a proton solid electrolyte for next-generation fuel cells.

An overview of Metal–Organic Frameworks as potential platform: Sensing for detection environmental pollutants and drug delivery applications

Metal Organic Frameworks (MOFs) represent a novel class of materials, characterized by their ability to form extended porous crystalline structures through the linkage of inorganic clusters or metallic ions with organic ligands. The availability of broad range of metal centres and type of organic linkers gives us opportunity for tailoring physical and chemical properties of MOFs. These modified MOFs opens up new channels for the customization of new devices needed for specific purposes. Though MOFs have been explored for significant applications in different sectors such as gas storage, proton conduction, biotechnological, biomedical sciences, catalysis, and separation, but drug delivery and the sensing applications has been taken exclusively at the manuscript. So, this article entails an overview of various synthetic methodology of low dimensional MOFs such as 1D and 2-D MOFs, and also focuses on their applications in sensing and drug delivery. This stems from their remarkable catalytic chemistry and their compatibility with a broad spectrum of materials. Furthermore, the 2-D layered structure of MOFs and their distinctive coordination of metal ions with organic ligands have emerging interest in the recent years.

Simultaneously improved H+ conductivity and H+/V4+ selectivity for all vanadium flow battery by ZIF-8 induced physical cross-linking

One of the major challenges in all vanadium redox flow battery (VRFB) is the trade-off between proton conductivity and vanadium ion cross-mixing. Here, we simultaneously enhanced proton conductivity and sharply reduced the vanadium crossover by introducing ZIF-8 into a sulfonated polyimide (6FTMA-100) to prepared a high performance VRFB membrane. Compared with the pristine membrane, the proton conductivity increased from 34.6 to 47.4 mS cm−1, and the vanadium ion permeation rates decreased from 3.56 × 10−7 to 0.82–1.88 × 10−7 cm2 min−1 with different ZIF-8 doping concentrations. The ZIF-8 doped membranes also showed increased viscosity, reduced membrane swelling ratio and increased Young's modulus. We propose this is due to the strong hydrogen bonding (−106.68 Kcal/mol) between the N in imidazole group and H in -SO3H. Battery performance confirmed that the optimized MMM-2 (2 % ZIF-8 loading) displayed the energy efficiency of 80 % at 160 mA cm−2 that much higher than its pristine 6FTMA-100, N117, and most of the reported sulfonated polyimides. This idea of creating physical crosslinked network provided an efficient way for achieving highly efficient VRFB membranes.

Optimising Ion Conductivity in NdBaInO4-Based Phases

Based on the previous work conducted by Fujii et al., NdBaInO4 compounds present modest oxide-ion conductivities. Therefore, it has been an attractive system of significant interest. In this study, we attempted to partially substitute Ca for Nd and the total electrical conductivity was successfully improved due to the generation of oxygen vacancies. The synthesis, crystal structure, density, surface topography, and electrical properties of NdBaInO4 and Ca-doped NdBaInO4 have been studied, respectively. NdBaInO4 and 10% and 20% molar fractions of Ca-doped NdBaInO4 were synthesized through solid-state reactions. The crystal structure of them was obtained from Le Bail refinement of the XRD pattern, giving the result of the monoclinic structure, which belongs to P21/c space group. The highest total electrical conductivity of 4.91 × 10−3 S cm−1 was obtained in the Nd0.9Ca0.1BaInO3.95 sample at a temperature of 760 °C in the dry atmosphere and the activation energy was reduced from 0.68 eV to 0.58 eV when the temperature was above 464 °C (737 K) after doping the NdBaInO4 with a 0.1 molar fraction of Ca2+. Moreover, the total conductivity of Nd0.9Ca0.1BaInO3.95 in the wet atmosphere at moderate temperature was relatively higher than that in the dry atmosphere, which suggests that potential proton conduction may exist in wet atmospheres. In addition, the oxygen diffusion coefficients of Nd0.9Ca0.1BaInO3.95 (D* = 1.82 × 10−8 cm2/s, 850 °C) was about two times higher than that of Nd0.8Ca0.2BaInO3.90 (D* = 7.95 × 10−9 cm2/s, 850 °C) and was increased significantly by two orders of magnitude when compared with the oxygen diffusion coefficient of the undoped NdBaInO4 (D* = 8.25 × 10−11 cm2/s, 850 °C).

Enhancing proton exchange membrane water electrolysis performance: Impact of iridium oxide catalyst ink dispersing methodology

Iridium oxide (IrO2) is the most successful catalyst for triggering oxygen revolution reactions in proton exchange membrane water electrolyzers (PEMWE). However, conventional ultrasonic methods for ink dispersion often result in ink instability, catalyst aggregation, and sedimentation. To address these issues, we investigate the effects of the dispersion type, treatment time, and ionomer-addition sequence on the catalytic performance. Ball-milling procedure prepares a more stable catalyst ink and achieves a larger electrochemical surface area (ECSA) than ultrasonic method. Extending the ball-milling time to 12 h improves the ink stability (absorbance change rate ∼0.6 % h−1); however, over-processing causes the thickest catalyst layer, leading to an enhanced mass transport resistance. Moreover, treating an ionomer with IrO2 causes the substitution of sulfonic acid groups by carboxylic acid groups and reduces the repulsive force in colloidal particles, resulting in poor ink stability, low proton conductivity, and small ECSA. Therefore, adding ionomer after ball milling is recommended for the preparation of a stable ink with high catalytic performance. The membrane electrode assembly prepared using this procedure exhibits an improved performance of 1.70 A cm−2 at 1.7 V, compared with that prepared using ultrasonic methods. This work provides crucial guidance of ink preparation for large-scale production of PEMWEs.

Influence of activated protons and acid–base pairs on proton conduction in imino-functionalized MOF-based hybrid membranes

The rich activated protons and effective proton-conducting paths are of importance to improve conductivities of conductors. Herein, a series of Brönsted acids as proton carrier and proton transfer sites is introduced into the highly stable MOF, contributing to create plentiful hydrogen bonds within frameworks. Consequently, the trifluoromethanesulfonic acid-embedded JUC-1000 ([Cu24(BDPO)12(H2O)12]) displays the relatively highest conductivity of 7.04 × 10−4 S cm−1 under ∼98% RH and 328 K, ∼16 times that of JUC-1000 (4.47 × 10−5 S cm−1). When TMSA@JUC-1000 (TMSA = CF3SO3H) blended with chitosan (CS), the proton conductivity of TMSA@JUC-1000/CS-15 is the highest at ∼76% RH and 328 K (1.01×10−2 S cm−1), which is six times higher than that of JUC-1000/CS (1.85×10−3 S cm−1). The CS contains abundant –NH2 and –OH groups as proton jumping sites, which would activate the –NH– or –OH bonds of JUC-1000 and the acidic groups in Brönsted acids. These would result in an increased content of activated protons and effective formation of H-bonding nets by acid-base interactions. The findings provide valuable insights into the potential application of MOFs materials in energy devices.

A novel solution for hydrogen monitoring in fusion processes: 3D printed BaCe0.6Zr0.3Y0.1O3-α sensors

The control of tritium (3H) in liquid-based tritium breeding blankets (TBBs) is one of the key points to assure their correct performance to prove the 3H sufficiency. For that, electrochemical sensors are a good option for tritium quantification since they can perform in-situ and online measurements.One of the multiple challenges for hydrogen detection is to find suitable materials that can operate at high temperatures and in harsh environments. In this context, perovskite-type ceramics, such as BaCe0.6Zr0.3Y0.1O3-α (BCZY), have elevated proton conductivity and exceptional stability even in reducing atmospheres and at elevated temperatures, which make them strong contenders for high-temperature hydrogen sensing applications.In the present study, we describe the development of a dual-mode hydrogen sensors based on 3D-printed BCZY, which allows a high degree of design flexibility. Crucible geometries were tested and characterized using X-ray diffraction and scanning electron microscopy. Electrochemical sensors were constructed and characterized at 400, 450 and 500 °C in both, amperometric and potentiometric configuration. The results demonstrated the capability of 3D-printed BCZY sensors for hydrogen detection in fusion reactors, offering a breakthrough solution for monitoring fusion processes.

Preparation and Characterization of SPEEK–PVA Blend Membrane Additives with Colloidal Silica for Proton Exchange Membrane Fuel Cell

AbstractAn inexpensive membrane with high proton conductivity and high fuel cell performance, which can be an alternative to Nafion for PEMFC (Proton exchange membrane fuel cell), will overcome the obstacle to widespread commercialization of fuel cells due to high cost. For this purpose, SPEEK (sulfonated polyether ether ketone)-PVA (polyvinyl alcohol) blend membranes with colloidal silica additives were synthesized in this study. Ludox AS-40 was used as the colloidal silica source and the blend membrane was prepared by solution casting method. Water uptake capacity, swelling property, size change, dynamic mechanical analysis, ion exchange capacity, AC impedance analysis, hydrolytic and oxidative stability experiments of the synthesized Ludox additives blend membranes for fuel cell application were carried out, and the membranes were also characterized by FTIR (Fourier transform infrared) analysis. While the water uptake capacities of SPEEK/PVA membranes containing 1% Ludox, 5% Ludox, and 10% Ludox at room temperature were found to be 14.08%, 14.84%, and 16.6%, respectively, the water uptake capacities at 80oC increased to 14.73%, 15.17%, and 17.11%. The proton conductivities of 1% Ludox, 5% Ludox and 10% Ludox doped SPEEK/PVA membranes at 80oC were 0.25 S/cm, 0.56 S/cm, and 0.65 S/cm, respectively. Similarly, ion exchange capacities were determined to be 1.41 meq/g, 1.63 meq/g, and 1.71 meq/g, respectively. All Ludox-added membranes exhibited excellent hydrolytic stability, retaining approximately 88% of their mass after 650 h. In addition, in oxidative stability experiments carried out in 4 ppm Fe+ 2 at 80oC, the 10% Ludox-added membrane exhibited the highest weight loss of 88.8% at the end of 24 h, while the 5% Ludox-additive membrane retained 91.6% of its total weight. Considering the proton conductivity and longevity tests of the synthesized membranes, they are thought to be promising structures. Graphical Abstract

Novel high temperature proton exchange membranes based on functionalized poly(arylene dimethylamino benzene) polymers

The electrolyte membrane is a critical component in high temperature proton exchange membrane fuel cells (HT-PEMFCs). We have developed a new triarylmethane-backboned polymer, poly(p-triphenyl dimethylamino benzene) (PTDB), by using p-triphenyl and 4-(dimethylamino)benzaldehyde as monomers through a one-step straightforward Friedel-Crafts reaction. The presence of tertiary amine groups in PTDB enables strong interaction with phosphoric acid (PA) molecules. To improve PA doping content and proton conductivity, both copolymers containing biphenyl repeat unite and side-chain quaternized polymers are synthesized. Results show that the 3-bromopropyl trimethylammonium bromide grafted membrane (PTDB-QA) outperforms the poly(triphenyl-biphenyl-dimethylamino benzaldehyde) (P(Tx%-By%-DB)) copolymer membranes. After being doped in an 85 wt% PA solution at 80 °C, the PTDB-QA membrane exhibits a PA uptake of 160%, resulting in an anhydrous proton conductivity of 0.054 S cm−1 at 180 °C and mechanical strength of 10.1 MPa at room temperature. Under the H2-air condition without any back pressure, the peak power density of a single cell based on PTDB-QA/160%PA reaches 230 mW cm−2 at 160 °C. This work presents a promising new membrane for HT-PEMFC applications.

Proton exchange membranes based on sulfonated polybutylene fumarate: Preparation and characterization

AbstractBased on a novel unsaturated polyester, polybutylene fumarate (PBF), a series of sulfonated proton exchange membranes were prepared and characterized for direct methanol fuel cell application. In this work, PBF underwent sulfonation at different degrees, and the optimum degree of sulfonation (DS) was identified by assessing the hydrolytic stability. In the second step, an effective strategy to enhance the membranes' proton conductivity was adopted by the addition of the 2‐(1H‐Imidazol‐2‐yl) acetic acid (Im‐COOH) compound as a proton‐conducting agent to the sulfonated PBF (SPBF) matrix with the optimum DS. The results unveiled significant alterations in the physicochemical properties of PBF due to sulfonation, including an elevation in water uptake and the glass transition temperature (Tg), accompanied by the disappearance of the crystallinity within SPBF. In terms of electrochemical characteristics, the SPBF‐17.5 PEM demonstrated a proton conductivity of 3.36 × 10−3 S cm−1 and a methanol permeability of 1.068 × 10−7 cm2 s−1, yielding a selectivity of approximately 31,460 S s cm−3. Furthermore, the attractive interactions between SO3H and NH groups further elevated proton conductivity to 4.12 × 10−3 S cm−1, accompanied by a decrease in methanol permeability to 0.942 × 10−7 cm2 s−1, enhancing the selectivity parameter to 43,736 S s cm−3.

Double cross-linked 3D layered PBI proton exchange membranes for stable fuel cell performance above 200 °C

Phosphoric acid doped proton exchange membranes often experience performance degradation above 200 °C due to membrane creeping and phosphoric acid evaporation, migration, dehydration, and condensation. To address these issues, here we present gel-state polybenzimidazole membranes with double cross-linked three-dimensional layered structures via a polyphosphoric acid sol-gel process, enabling stable operation above 200 °C. These membranes, featuring proton-conducting cross-linking phosphate bridges and branched polybenzimidazole networks, effectively anchor and retain phosphoric acid molecules, prevent 96% of its dehydration and condensation, improve creep resistance, and maintain excellent proton conductivity stability. The resulting membrane, with superior through-plane proton conductivity of 0.348 S cm−1, delivers outstanding peak power densities ranging from 1.20–1.48 W cm−2 in fuel cells operated at 200-240 °C and a low voltage decay rate of only 0.27 mV h−1 over a 250-hour period at 220 °C, opening up possibilities for their direct integration with methanol steam reforming systems.

Ternary Holey Carbon Nanohorn/Potassium Chloride/Polyvinylpyrrolidone Nanohybrid as Sensing Film for Resistive Humidity Sensor

The study presents findings on the relative humidity (R.H.) sensing capabilities of a resistive sensor. This sensor utilizes sensing layers composed of a ternary nanohybrid, consisting of holey carbon nanohorn (CNHox), potassium chloride (KCl), and polyvinylpyrrolidone (PVP), with mass ratios of 7/1/2, 6.5/1.5/2, and 6/2/2 (w/w/w). The sensing structure comprises a silicon substrate, a SiO2 layer, and interdigitated transducer (IDT) electrodes. The sensing film is deposited on the sensing structure via the drop-casting method. The sensing layers’ morphology and composition are investigated through Scanning Electron Microscopy (SEM) and RAMAN spectroscopy. The resistance of thin-film sensors based on ternary hybrids increased with exposure to a range of relative humidity (R.H.) levels, from 0% to 100%. The newly designed devices demonstrated a comparable response at room temperature to that of commercial capacitive R.H. sensors, boasting excellent linearity, swift response times, and heightened sensitivity. Notably, the studied sensors outperform others employing CNHox-based sensing layers in terms of sensitivity, as observed through manufacturing and testing processes. It elucidates the sensing mechanisms of each constituent within the ternary hybrid nanocomposites, delving into their chemical and physical properties, electronic characteristics, and affinity for water molecules. Various alternative sensing mechanisms are considered and discussed, including the reduction in holes within CNHox upon interaction with water molecules, proton conduction, and PVP swelling.

A New Composite Proton Conductor as a High-Performance Electrolyte toward Low-Temperature Protonic Ceramic Cells

A New Composite Proton Conductor as a High-Performance Electrolyte toward Low-Temperature Protonic Ceramic Cells

Oxygen Vacancies Boosted Hydronium Intercalation: A Paradigm Shift in Aluminum‐based Batteries

In aqueous aluminum‐ion batteries(AAIBs), the insertion/extraction chemistry of Al3+ often leads to poor kinetics, whereas the rapid diffusion kinetics of hydrated hydrogen ions (H3O+) may offer the solution. However, the presence of considerable Al3+ in the electrolyte hinders the insertion reaction of H3O+. Herein, we report how oxygen‐deficient α‐MoO3 nanosheets unlock selective H3O+ insertion in a mild aluminum‐ion electrolyte. The abundant oxygen defects impede the insertion of Al3+ due to excessively strong adsorption, while allowing H3O+ to be inserted/diffused through the Grotthuss proton conduction mechanism. This research advances our understanding of the mechanism behind selective H3O+ insertion in mild electrolytes.

Constructing sandwich-like microstructure based on multi-nanofibers to accelerate proton conduction at subzero temperature

The well-ordered microstructure has been demonstrated to accelerate the proton conduction process through reducing proton conduction resistance. In this research, the proton exchange membranes (PEMs) with sandwich-like microstructure have been constructed based on Kevlar nanofibers and bifunctional nanofibers of chitosan (CS) with polyvinyl alcohol (PVA). The CS/PVA bifunctional nanofibers (CPNF) layer has been prepared with electrospinning process, which is stably adhered to the Kevlar nanofibers layer owing to compatible interfacial property. The fine structure stability without layer separation is achieved even with phosphoric acid (PA) molecules doping in the prepared PA doped composite membranes. The fibrous microstructure accelerats proton conduction through regulating proton conduction pathways. The objective of accelerating proton conduction at subzero temperature has been realized, reflecting in high and stable proton conductivities. For instance, the (Kevlar/CPNF/Kevlar)/PA membrane exhibits proton conductivities of 9.75 × 10−3 S/cm at −30 °C and 8.22 × 10−2 S/cm at 30 °C. Most importantly, the fine proton conductivity stability is identified by the results of the cycle test and long-term test. Specifically, the proton conductivities are respectively 8.62 × 10−3 S/cm at −30 °C and 8.07 × 10−2 S/cm at 30 °C after a five heating/cooling cycle process. The proton conductivities remain 2.97 × 10−2 S/cm at −25 °C and 7.19 × 10−2 S/cm at 30 °C after a 1032 h non-stop test. Additionally, the single proton exchange membrane fuel cell with the (Kevlar/CPNF/Kevlar)/PA membrane exhibits the peak power densities of 279.5 mW/cm2 at 100 °C and 352.7 mW/cm2 at 130 °C.

Eco-friendly, low-cost, and antibacterial PEM boosts microbial fuel cell performance: Power generation and wastewater treatment

The performance of microbial fuel cells (MFCs) relies significantly on the proton exchange membrane (PEM). While effective, commercial options like Nafion 117 are costly and possess inherent weaknesses. Improving methods of PEMs are generally used, requiring spending energy and money and causing harmful and toxic chemicals to enter the environment. This study introduces an innovative approach by enhancing sulfonated polyether sulfone (SPES) properties using Falcaria vulgaris extract, offering a simple, environmentally friendly, cost-effective solution. The resulting green functionalized SPES membranes (GFSPESs) were evaluated in dual-chamber MFCs for energy production and textile wastewater treatment. SPES membranes were fabricated through a phase inversion process and subsequently functionalized using dip-coating, heating, and UV irradiation. Comprehensive analysis, including FTIR, EDS, SEM, and XPS, investigated the physicochemical structure of the PEMs. The plant extract exhibited notable benefits, enhancing hydrophilicity, proton conductivity, and antibacterial capability of the PEMs. The MFC with GFSPES-12 achieved a peak power output of 86.3 mW/m2 and a maximum current of 327 mA/m2, surpassing the performance of Nafion 117 and the bare SPES membranes. GFSPES-12 also exhibited a maximum ion exchange capacity (1.89 meq/g) and proton conductivity (2.98 mS/cm). In textile wastewater treatment, the GFSPESs demonstrated improved COD removal (96.12 %) and higher coulombic efficiency (42.23 %). Notably, GFSPES-12 exhibited an antibacterial efficiency exceeding 93.5 %. These findings affirm the efficient functionality of GFSPES membranes in dual-chamber MFCs, offering a promising and sustainable alternative for energy production and wastewater treatment.

Imparting Stable and Ultrahigh Proton Conductivity to a Layered Rare Earth Hydroxide via Ion Exchange.

Proton conductors are essential functional materials with a wide variety of potential applications in energy storage and conversion. In order to address the issues of low proton conductivity and poor stability in conventional proton conductors, a simple and valid ion-exchange method was proposed in this study for the introduction of stable and ultrahigh proton conductivity in layered rare earth hydroxides (LRHs). Test analyses by solid-state nuclear magnetic resonance, Fourier transform infrared spectroscopy, and powder X-ray diffraction revealed that the exchange of H2PO4- not only does not disrupt the layered structure of LRHs, but also creates more active proton sites and channels necessary for proton transport, thereby creating a high-performance proton conductor (LRH-H2PO4-). By utilizing this ion-exchange method, the proton conductivity of LRHs can be significantly enhanced from a low level to an ultrahigh level (>10-2 S·cm-1), while maintaining excellent long-term stability. Moreover, through methodically manipulating the guest ions and molecules housed within the interlayers of LRHs, a comprehensive explanation has been presented regarding the proficient mechanism of proton conduction in LRH-H2PO4-. As a result, this investigation presents a feasible and available approach for advancing proton conductor.