Acid Stability Research Articles

Research Progress of High-entropy Oxides for Electrocatalytic Oxygen Evolution Reaction.

High-entropy oxides (HEOs), similar to high-entropy materials (HEMs), have "four-core effects", i. e., high-entropy effect, delayed diffusion effect, lattice distortion effect and cocktail effect, which have attracted more and more attention in the scientific field of renewable energy technology due to their unique structural characteristics, variable chemical composition and corresponding functional properties. HEOs have become potential candidates for electrocatalytic oxygen evolution reaction (OER), which is a key half reaction for electrolytic CO2, nitrogen reduction, and water electrolysis. However, the precise synthesis of HEOs with a wide range of components and structures is challenging, not to mention their active and stable operation for OER. In this paper, we review the recent advancements in the electrocatalytic oxygen evolution facilitated by HEOs in water electrolysis. We analyze these developments from the perspectives of activity and stability in acid and alkaline conditions, respectively. Furthermore, we summarize the design from the aspect of element composition, structure, morphology, and catalyst-support interactions, along with related reaction mechanism of HEOs. Additionally, we discuss the current challenges faced by HEOs in the field of OER and suggest potential directions for the future development of HEOs beyond water electrolysis application.

Microenvironment Control over Electrocatalytic Activity of g-C3N4/2H-MoS2 Superlattice-like Heterostructures for Hydrogen Evolution.

Microenvironments in heterogeneous catalysis have been recognized as equally important as the types and amounts of active sites for regulating catalytic activity. Two-dimensional (2D) nanospaces between van der Waals (vdW) gaps of layered materials provide an ideal microenvironment to create novel functionalities. Here, we explore a facile method for fabricating g-C3N4/2H-MoS2 superlattice-like heterostructures based on thermochemical intercalation and polymerization reactions of formamide within enlarged vdW gaps of 2H-MoS2 nanosheets without any transfer process. DFT calculations demonstrate that the interlayer electron-electron correlations due to the intercalation effect of g-C3N4, rather than high-κ dielectric environments, lead to the improvement of intrinsic conductivity of 2H-MoS2 nanosheets. As the proof of concept in applications for the electrocatalysis field, the heterostructure for hydrogen electrochemical reaction (HER) exhibits high stability and catalytic activity in both acid and alkaline media, such as a quite low onset overpotential of 98 mV, a high exchange current density of 77.6 μA cm-2, and a small Tafel slope (52.9 mV dec-1) in an acid medium. The enhanced HER activity is attributed to the improved conductivity and nanoconfinement effect of 2D nanospaces that decrease the reaction activation energy and activate the inert basal planes.

Grapevine and maize: Two guard cell shaped strategies to cope with repeated drought stress

Adaptation of crops to recurrent drought stress is crucial for maintaining agricultural productivity and achieving food security under changing climate. Guard cells, pivotal regulators of plant water usage and assimilation, are central to this adaptation process. However, the metabolic dynamics of guard cells under drought stress remain poorly understood, particularly in grapevine, a prominent crop grown in arid regions, and maize, a staple crop with substantial water requirements. In this study, differences in guard cells metabolism during drought stress of grapevine and maize were investigated by performing physiological and metabolomic analyses. Metabolomic analysis highlighted differential responses in amino acids and sugars, with grapevine guard cells displaying greater stability in amino acid and sugar signatures, while maize showed marked increases in sugar levels. These findings suggest two distinct adaptive strategies, a vigorous acclimation of guard cells, as observed in maize, and an attenuated acclimation of guard cells, shown in grapevine. Understanding these metabolic adjustments is helpful for enhancing drought resilience in agricultural systems.

High-valence Co deposition based on selfcatalysis of lattice Mn doping for robust acid water oxidation

Non-precious metal cobalt-based oxide inevitably dissolves for acid oxygen evolution reaction (OER). Designing an efficient deposition channel for leaching cobalt species is a promising approach. The dissolution-deposition equilibrium of Co is achieved by doping Mn in the lattice of LaCo1−xMnxO3, prolonging the lifespan in acidic conditions by 14 times. The lattice doping of Mn produces a strain that enhances the adsorption capacity of OH−. The self-catalysis of Mn causes the leaching Co to be deposited in the form of CoO2, which ensures that the long-term stability of LaCo1−xMnxO3 is 70 h instead of 5 h for LaCoO3. Mn doping enhances the deprotonation of *OOH→O2 in acidic environments. Notably, the overpotential of optimized LaCo1−xMnxO3 is 345 mV at 10 mA cm−2 for acidic OER. This work presents a promising method for developing noble metal-free catalysts that enhance the acidic OER activity and stability.

Towards highly efficient and stable perovskite solar cells: suppressing ion migration by inorganic boric acid stabilizer

The poor stability of organic-inorganic perovskite solar cells is commonly ascribed to elevated ion migration, stemming from the low electronegativity of iodine. To address this issue, boric acid was chosen as a stabilizer for perovskite thin films. As a Lewis acid, the boric acid has a sp2 hybridized boron atom, which can readily accept a pair of electrons from iodine ion into their vacant unhybridized p orbital, and the formation of the Pb-O bond further increases the iodide migration barrier. The significantly increased barrier of the iodine ion migration was demonstrated by the improved phase stability of the perovskite film under an electric field and the obviously enhanced stability of the perovskite films under strong ultraviolet light. PSCs that included the BA stabilizer were able to achieve an enhanced PCE of 25.52%. The initial efficiency of BA-modified devices remained at 80% even after being aged for 1000hours at 85 ℃ under around 30% relative humidity (RH). When subjected to maximum power point tracking and 20-25% RH, the PCE of BA-modified devices maintained an initial efficiency of 80% after 1500hours.

The content and stability of ascorbic acid in commercial food supplements

The content and stability of ascorbic acid in commercial food supplements

QbD decorated ellagic acid loaded polymeric nanoparticles: Factors influencing desolvation method and preliminary evaluations

Polymeric nanoparticles are one of the emerging drug delivery systems in the field of oncology. Ellagic acid is a polyphenolic compound with vast effects like anti-cancer, anti-viral, and anti-oxidant. The ellagic acid nanoparticles was prepared by desolvation method. Formulating ellagic acid NPs using BSA enhances the stability and solubility of ellagic acid. Quality by design (QbD) based approach was adopted to improve the final quality and effectiveness of the formulation. The Critical quality attribute (CQAs) was defined and risk assessment was performed with the help of the Ishikawa fishbone diagram. Solubility analysis was done for the drug with methanol, ethanol, water, and acetone. Preliminary studies were performed to study the effect of type of desolvating agent, the concentration of polymer the pH of the polymer solution, amount of desolvating agent on the particle size and entrapment efficiency of the nanoparticles. A greater quantity of desolvating agent results in a narrower particle size because of thorough desolvation, and the increased encapsulation efficiency is linked to reduced protein-protein interactions. Desolvation process can cause the protein to gradually change structure, form clumps, and eventually form nanoparticles, so might be its shows increase in entrapment efficiency. A desolvating agent volume of 4 ml resulted in a particle size of 1724 ± 1.27 nm. When the amount of desolvating agent was increased to 6 ml and 8 ml, the particle size decreased to 160 ± 0.66 nm and 218 ± 0.47 nm, respectively. Fourier Transform Infrared Spectroscopy (FTIR) data showed no incompatibilities were observed between drug and polymer. In-vitro dissolution showed the nanoparticles may follow the control release pattern over 24 hours. All the formulated batches of zeta potential were found to be in the range −30 mV to +30 mV which indicated good colloidal stability of the NPs and the PDI value ranging from 0.18 to 2.8. The higher drug encapsulation of the drug was more than 50 % which gives higher drug release at a site of action and in-vitro drug release of more than 80 % may improve the dosage frequency. The in vitro drug release data was also studied by various kinetic models. The in vitro drug release analysis shows sustained release of drug from nanoparticles and follow Korsmeyer-Peppas model. All these findings were in good agreement which may open a new gateway for future research in the field of oral oncology.

Effects of nickel-deactivations on zeolites-Y of different SiO2/Al2O3 ratios in catalytic cracking of hydrocarbons

Effects of nickel deactivation on catalytic activities of three types of zeolites-Y (Y-5.1, USY-5.2, and VUSY-12) with varying SiO2/Al2O3 ratios were studied in cracking of hydrocarbons. Physicochemical characteristics such as crystalline phases, Ni oxidation states, morphology, acidity, surface area, and thermal stability of the samples were analysed. XRD revealed the absence of observable nickel compounds below 5 wt%, with NiO phase emerging at higher concentrations. Surface areas decreased from 826 to 615 m2/g (Y-5.1), 786–686 m2/g (USY-5.2), and 762–571 m2/g (VUSY-12) at 30 wt% Ni. The total acid sites also reduced from 17.247 to 9.826 µmol/g (Y-5.1), 15.464–8.854 µmol/g (USY-5.2), and 7.094–4.876 µmol/g (VUSY-12). XPS confirmed Ni2+ states. Catalytic cracking tests using n-Heptane demonstrated increases in C5-C6 alkanes, olefins, hydrogen, and methane yields as nickel concentration increased, with respective values of 64 %, 28 %, 79 % and 68 % for Y-5.1; 62 %, 28 %, 76 %, and 62 % for USY-5.2; and 58 %, 21 %, 75 %, and 60 % for VUSY-12. A corresponding decrease in heavier components were observed. The study demonstrates that nickel modification significantly impacts the physicochemical properties and catalytic performance of zeolite-Y and these depend strongly on the SiO2/Al2O3 ratios. The study gives further insights into the structural and catalytic modifications induced by nickel doping in zeolites, highlighting the potential of nickel-modified zeolites in promoting undesirable hydrogen and gas.

Rapid Preparation of Platinum Catalyst in Low-Temperature Molten Salt Using Microwave Method for Formic Acid Catalytic Oxidation Reaction.

In this paper, platinum nanoparticles with a size of less than 50 nm were rapidly and successfully synthesized in low-temperature molten salt using a microwave method. The morphology and structure of the product were characterized by SEM, TEM, EDX, XRD, etc. The TEM and SEM results showed that the prepared product was a nanostructure with concave and uniform size. The EDX result indicated that the product was pure Pt, and the XRD pattern showed that the diffraction peaks of the product were consistent with the standard spectrum of platinum. The obtained Pt/C nanoparticles exhibited remarkable electrochemical performance in a formic acid catalytic oxidation reaction (FAOR), with a peak mass current density of 502.00 mA·mg-1Pt and primarily following the direct catalytic oxidation pathway. In addition, in the chronoamperometry test, after 24 h, the mass-specific activity value of the Pt concave NPs/C catalyst (10.91 mA·mg-1Pt) was approximately 4.5 times that of Pt/C (JM) (2.35 mA·mg-1Pt). The Pt/C NPs exhibited much higher formic acid catalytic activity and stability than commercial Pt/C. The microwave method can be extended to the preparation of platinum-based alloys as well as other catalysts.

BF3 ⋅ OEt2 as a Versatile Reagent: Applications in Organic Synthesis

AbstractBoron trifluoride diethyl etherate, commonly referred to as BF3 ⋅ OEt2, plays a crucial role as a potent reagent in various organic transformations, particularly in the synthesis of heterocyclic systems through the establishment of carbon‐carbon & carbon‐heteroatom bonds. Its Lewis acid properties, reactivity, and stability at room temperature make it essential for a wide range of chemical reactions. BF3 ⋅ OEt2 demonstrates remarkable efficacy in processes such as hydroxylation of double bonds, epoxide cleavage, acid esterification, cyanation, coupling, and diverse cyclization reactions, surpassing other Lewis acids in performance. Its significant impact on organic synthesis extends to the formation of natural products, highlighting its profound significance in the realm of chemistry. The unique properties and versatility of boron trifluoride diethyl etherate make it a fundamental tool for a diverse array of chemical transformations. The numerous applications of this reagent in organic synthesis have prompted the development of a comprehensive review, focusing on its various roles and contributions in this field.

Stacking correlation length in single-stranded DNA.

Base stacking is crucial in nucleic acid stabilization, from DNA duplex hybridization to single-stranded DNA (ssDNA) protein binding. While stacking energies are tiny in ssDNA, they are inextricably mixed with hydrogen bonding in DNA base pairing, making their measurement challenging. We conduct unzipping experiments with optical tweezers of short poly-purine (dA and alternating dG and dA) sequences of 20-40 bases. We introduce a helix-coil model of the stacking-unstacking transition that includes finite length effects and reproduces the force-extension curves. Fitting the model to the experimental data, we derive the stacking energy per base, finding the salt-independent value $\Delta G_0^{ST}=0.14(3)$ kcal/mol for poly-dA and $\Delta G_0^{ST}=0.07(3)$ kcal/mol for poly-dGdA. Stacking in these polymeric sequences is predominantly cooperative with a correlation length of ∼4 bases at zero force . The correlation length reaches a maximum of ∼10 and 5 bases at the stacking-unstacking transition force of ∼10 and 20 pN for poly-dA and poly-dGdA, respectively. The salt dependencies of the cooperativity parameter in ssDNA and the energy of DNA hybridization are in agreement, suggesting that double-helix stability is primarily due to stacking. Analysis of poly-rA and poly-rC RNA sequences shows a larger stacking stability but a lower stacking correlation length of ∼2 bases.

The host tropism of current zoonotic H7N9 viruses depends mainly on an acid-labile hemagglutinin with a single amino acid mutation in the stalk region.

The incidence of human infection by zoonotic avian influenza viruses, especially H5N1 and H7N9 viruses, has increased. Current zoonotic H7N9 avian influenza viruses (identified since 2013) emerged during reassortment of viruses belonging to different subtypes. Despite analyses of their genetic background, we do not know why current H7N9 viruses are zoonotic. Therefore, there is a need to identify the factor(s) responsible for the extended host tropism that enables these viruses to infect humans as well as birds. To identify H7N9-specific amino acids that confer zoonotic properties on H7N9 viruses, we performed multiple alignment of the hemagglutinin (HA) amino acid sequences of A/Shanghai/1/2013 (H7N9) and A/duck/Zhejiang/12/2011(H7N3) (a putative, non- or less zoonotic HA donor to the zoonotic H7N9 virus). We also analyze the function of an H7N9 HA-specific amino acid with respect to HA acid stability, and evaluated the effect of acid stability on viral infectivity and virulence in a mouse model. HA2-116D, preserved in current zoonotic H7N9 viruses, was crucial for loss of HA acid stability. The acid-labile HA protein in H7 viruses played an important role in infection of human airway epithelial cells; HA2-116D contributed to infection and replication of H7 viruses. Finally, HA2-116D served as a H7 virulence factor in mice. These results suggest that acid-labile HA harboring HA2-116D confers zoonotic characteristics on H7N9 virus and that future novel zoonotic avian viruses could emerge from non-zoonotic H7 viruses via acquisition of mutations that remove HA acid stability.

Stability of the Glycated Amino Acid 6-(2-Formyl-5-hydroxymethyl-1-pyrrolyl)-l-norleucine (Pyrraline) During Oxidation.

Food proteins may be modified during processing and storage through reactions with reducing sugars (Maillard reaction, glycation) or by reactive oxygen species (protein oxidation). Little is known about particular reactions at the interface of glycation and oxidation. In the present study, the glycated amino acid pyrraline (6-(2-formyl-5-hydroxymethyl-1-pyrrolyl)-l-norleucine) and the proteinogenic amino acids tyrosine and tryptophan were subjected to different types of oxidation. The stability of the amino acids was assessed by HPLC with UV detection, whereas oxidation products were assigned by HPLC with triple quadrupole or time-of-flight mass spectrometric detection. Conditions that lead to oxidation of aromatic proteinogenic amino acids can also lead to oxidation of pyrraline. Pyrraline was particularly unstable in the presence of permanganate, hypochlorite, and under hydroxyl radical-generating conditions (iron, ethylenediaminetetraacetic acid, ascorbic acid). Evidence obtained by high-resolution mass spectrometry revealed the oxidation of pyrraline to 6-(2,5-diformyl-1-pyrrolyl)-l-norleucine, 6-(2-carboxy-5-hydroxymethyl-1-pyrrolyl)-l-norleucine, 6-(2-formyl-5-carboxy-1-pyrrolyl)-l-norleucine, and 6-(2,5-dicarboxy-1-pyrrolyl)-l-norleucine in the presence of potassium permanganate. The latter product was isolated by semipreparative HPLC and characterized by NMR. Under hydroxyl radical-generating conditions, pyrraline is hydroxylated at the ring under formation of 6-(2-formyl-4-hydroxy-5-hydroxymethyl-1-pyrrolyl)-l-norleucine or 6-(2-formyl-3-hydroxy-5-hydroxymethyl-1-pyrrolyl)-l-norleucine. This study shows that the so-called "advanced glycation end products" are no end products of the Maillard reaction, but may undergo further chemical degradation reactions.

Mechanistic insights into lipid extraction from wet microalgae using hydrophobic deep eutectic solvents under hydrothermal conditions

Hydrophobic deep eutectic solvents (HDESs) were first employed under hydrothermal conditions to form a two-phase system for instantaneous and efficient lipid extraction from wet microalgae, preventing lipid degradation and avoiding the use of toxic solvents. Ten HDESs were assessed for their efficiency and selectivity in lipid extraction. Among them, OCT-DEC, composed of octanoic acid and decanoic acid, achieved the highest extraction efficiency at 95.42 %, while also preventing the co-extraction of proteins and reducing sugars. Molecular dynamics simulations revealed that lipid extraction efficiency is primarily influenced by lipid-HDES interactions, which drive lipid diffusion, and the interfacial properties of the two-phase hydrothermal system, which resist lipid diffusion. The superior performance of OCT-DEC is attributed to its high hydrogen bond density and short bond lifetimes, which, combined with its structural stability, synergistically reduce resistance to lipid diffusion at the interface. Additionally, OCT-DEC significantly enhances the thermal stability of unsaturated fatty acids, such as C20:5, effectively preventing the degradation of high-value lipids and highlighting its potential for hydrothermal extraction of these valuable compounds.

Fatty acid composition, lipid profile and oxidative stability of meat of broiler chickens fed diet containing bird eye pepper of varying inclusion level and sieve size.

Nutritional modifications to improve meat quality is targeted by farmers. Bird eye pepper (BEP) contains bio-compounds of physiological significance. The potency of BEP of varying inclusion level and sieve size on meat quality [fatty acid (FA), lipid profile and oxidative stability] of broiler chickens was investigated. A total of 246 birds fed diet-containing BEP [inclusion level (0, 0.15 and 0.3%), sieve size (0.05 and 0.1mm)] were randomized to six treatments replicated 4 times in a 2 by 3 factorial layout. After feeding (31 days), forty-eight birds (two per replicate) were slaughtered and breast muscles harvested. Meat lipid profile and 2-thiobarbituric acid reactive substance (TBARs) were determined on day (d) 0, while TBARs was further assessed on d 3 and 5, but FA on d 10 of refrigeration storage. BEP diet (0.15%) increased (p < 0.05) total monounsaturated FA (MUFA), unsaturated FA (UFA) and n-3 FA, while 0.05mm BEP lowered (p < 0.05) meat index of thrombogenicity (TI) but increased meat hypocholesteromic: hypercholesteromic (HH) value. Dietary 0.15% (0.05mm) BEP yielded low (p < 0.05) SFA but high MUFA: SFA, UFA: SFA and NVI, while 0.15% (0.1mm) BEP diet resulted in high total MUFA and higher (p < 0.05) UFA, n-3 and n-3: n-6 FA. Control, 0.15% and 0.05mm BEP diets reduced (p < 0.05) meat cholesterol value. This study has shown that 0.15% (0.05mm) BEP diet had no deleterious effect on the growth of broiler chickens but improved the NVI, IA, TI, HH, TBARs and cholesterol of the meat - a significance to health-conscious consumers.

Characterizing and optimizing glutamate decarboxylase from Priestia flexa for efficient biosynthesis of γ-aminobutyric acid from l-glutamic acid powder

Gamma-aminobutyric acid (GABA) is widely applied in the food and pharmaceutical industries, and is experiencing a continually growing market demand. Nevertheless, the efficient and stable production of GABA confronts challenges, especially the instability of its core enzyme, glutamate decarboxylase (GAD). GAD exhibits high activity under acidic conditions but very poor stability. This limitation severely restricts its application in large-scale industrial production. In this study, we identified and characterized a GAD from Priestia flexa (PfGAD) with high activity. We further developed a variant with significantly enhanced acidic st ability. The specific activity of the variant achieved 139.8 U/mg, and its residual activity remained approximately 90 % after overnight incubation in pH 3.0 buffer. Moreover, we engineered a strain by overexpressing a transporter protein for GABA and l-glutamic acid, while deleting the pepD gene. The yield of GABA led to 251.8 g L−1, accompanied by a conversation rate of 97.8 %, meanwhile the cell growth maintained normal. Our approach successfully addresses the challenge of balancing cell growth and GABA accumulation. Our findings offer valuable insights into acid resistance modification of the enzyme, and optimizing GABA production through strain modification, holding significant potential for the industrial application of GABA.

Porous and B‐site Substituted Y2[Mn0.2Ru0.8]2O7 Pyrochlore for Boosting Acidic Water Oxidation Activity and Stability

Boosting the reaction stability without sacrificing the activity and cost is extremely important but full of challenging for the RuO2‐based oxygen evolution catalysts. Herein, porous and B‐site substituted Y2[Mn0.2Ru0.8]2O7 (p‐Y2[Mn0.2Ru0.8]2O7) pyrochlore toward oxygen evolution reaction is innovatively synthesized. The formed meso/macro‐porous structure can increase the specific surface area and corresponding active sites, meanwhile, Mn‐substitution can modulate the electronic structure, stabilize the morphology, and reduce the dosage of Ru species. Excitingly, the p‐Y2[Mn0.2Ru0.8]2O7 performs 50 h stable operation, significantly outperforming the commercial RuO2(CM) counterpart with less than 2 h life. Furthermore, the required overpotential to achieve 10 mA cm‐2 is only 266 mV, accompanied with favorable reaction kinetics and catalyst utilization.

Yeast cell biocarrier for the encapsulation of ascorbic acid: effect of plasmolysis process, suspension media and ascorbic acid levels on the physicochemical, morphological and bioactive properties of microcapsules.

Ascorbic acid is a water-soluble vitamin and shows weak stability against external factors such as heat, oxygen, light etc. Due to its lower stability, encapsulation is an effective process for the preservation of its activity. Although there are a wide variety of encapsulation methods, the technique of encapsulation with yeast cells has been followed with increasing interest in recent years. In this study, encapsulation possibilities of ascorbic acid by yeast cells were investigated. In this context, Saccharomycess cerevisiae yeast cells in plasmolyzed and non-plasmolyzed forms were used in two different suspension media (water and ethanol) and effect of ascorbic acid concentrations (10, 20 and 50 g per 10 g yeast) were studied. A total of 12 different yeast microcapsule samples were produced and some physicochemical, bioactive and structural characterizations were performed. The ascorbic acid level of yeast microcapsule samples was determined as 206.4-713.9 and 202.8-726.1 mg g-1 for plasmolyzed and non-plasmolyzed yeast cell types, respectively. ABTS radical scavenging activity increased from 27.23 to 233.04 μg TE g-1 by increased ascorbic acid levels. Ascorbic acid capsules were used in soft candy processing against free ascorbic acid and it was found that 47.9% ascorbic acid loss was detected for control sample at the 24-day storage while the ascorbic acid loss was approximately 25% for yeast microcapsules. It was concluded that yeast cells are capable of preserving ascorbic acid stability during storage and yeast cells can be used effectively and safely for the manufacturing of the ascorbic acid microcapsules. © 2024 Society of Chemical Industry.

Magnetic chitosan supported copper particles as a heterogeneous catalyst for benzaldehyde glycol acetal reaction

In this work, a series of magnetic chitosan (CS) supported-metal catalysts were successfully prepared for the acetalization of benzaldehyde (BzH) with ethylene glycol (EG). The structural properties of the catalysts were characterized by TEM, FT-IR, XRD, XPS, TGA-DTG, SEM-EDX and VSM. The results showed that Fe3O4-CS-Cu(20 %) catalyst possessed the best catalytic efficiency in all prepared catalysts due to its suitable acidity and excellent stability when they were utilized in the acetalization reaction to generate benzaldehyde glycol acetal. The response surface methodology based on Box-Behnken design was applied to optimize acetalization reaction conditions with the optimal yield of 96.26 % obtained via 3D surface diagram. The attractive feature of prepared catalysts was easy separation from solutions via an external magnetic field application. This work sheds light on the design of novel chitosan-supported metal catalysts which could be widely applied in acetalization industry.

High-density quaternized polymer ionic liquid/polybenzimidazole cross-linked membrane achieves excellent acid stability

High-temperature proton exchange membranes (HT-PEMs) were created by incorporating quaternate polymeric ionic liquids (PILs) with a triazine structure into polybenzimidazole (OPBI). The membranes that were developed demonstrate excellent proton transport and retention capabilities for phosphoric acid (PA). It was found that the best overall performance of the cross-linked membranes was achieved at the ideal ratio of 30 wt% PIL. The proton conductivity of OPBI-PIL-30 % membranes at 180 °C was 126.71 mS cm−1. The PA retention was 69.37 % after 240 h of testing at 80 °C and 40 % RH. The PA retention was 91.61 % at 160 °C, indicating its superior acid retention ability. The OPBI-PIL-30 % membrane was assembled into a single cell with a peak power density of 448.99 mW cm−2 at a current density of 1490 mA cm−2. These excellent performances suggest that cross-linked composite membranes containing bulky structures and quaternary ammonium groups are one of the potential materials for HT-PEMs.