Zirconium Phosphate Research Articles

Catalytic Application of Cs‐Substituted Phosphotungstic Acid (CsxH3‐xPW12O40)‐Mesoporous Zirconium Phosphate (m‐ZrP) Nanocomposite Towards Synthesis of Structurally Diverse Tetrazole Moieties

AbstractThe rational design of a high surface area heterogeneous nanocomposite catalyst with well‐defined surface acidic sites and structural porosity is a promising approach with potential application in expeditious synthesis of biologically active molecules/scaffolds. In this work, mesoporous zirconium phosphate (m‐ZrP) was synthesized through a hydrothermal process and used as a porous matrix for dispersion of cesium‐exchanged phosphotungstic acid (CsxH3‐xPW12O40) nanoparticles to prepare CsxH3‐xPW12O40‐mZrP nanocomposite systems. Various characterization techniques, including XRD, UV–vis‐DRS, FTIR, FESEM, HRTEM, TGA‐DTA, BET, and TPD, were used to understand the structural, morphological, and surface properties of the composites. XRD analysis revealed the presence of m‐ZrP and cubic CsxH3‐xPW12O40 crystalline phases in the nanocomposite materials. A microscopic study indicated the existence of rod‐shaped morphology that was formed by the coalescence of a large number of spherical nanoparticles with diameters between 150 and 200 nm. The dispersion of CsxH3‐xPW12O40 over the m‐ZrP surface results in significant enhancement of medium and strong acidic sites, with the maximum number of acidic sites observed for the Cs0.5‐PTA‐mZrP composite (0.406 mmol g−1). The catalytic activity of the CsxH3‐xPW12O40‐mZrP nanocomposites was evaluated for rapid synthesis of tetrazole derivatives through [3 + 2] cycloaddition reactions of substituted nitrile and NaN3 under mild conditions. The detailed optimization study revealed that the use of Cs0.5‐PTA‐mZrP catalyst in DMF media afforded 90% yield of the tetrazole at 120 °C. Reaction kinetics study suggested that the optimal Cs0.5‐PTA‐mZrP catalyst exhibited the highest reaction rate of 2.06 × 10−3 mmol h−1m−2 towards tetrazole formation. Structurally diverse tetrazole derivatives in high yield and purity were synthesized under mild conditions using CsxH3‐xPW12O40‐mZrP nanocomposite as catalyst.

Sonochemical synthesis of guar gum - Zirconium phosphate composite for efficient capture of uranium from water

The increasing presence of uranium as a radionuclide contaminant in water is a threat to human health and the environment. Sonication-assisted crosslinking of guar gum, a biopolymer, is carried out with zirconium phosphate to form an adsorbent (GG@ZrP) for the removal of uranium from water. The surface characteristics, functionalities, and thermal stability of the composite were established using various analytical and spectral tools. Langmuir, Freundlich, and Sips models were used to evaluate the batch adsorption parameters. The adsorbent exhibited an excellent Langmuir adsorption capacity of 500 mg g−1 towards adsorption of uranium at pH 6. The adsorption was endothermic (ΔH, 22.63 kJ mol−1) and followed pseudo-second order kinetics. The synergistic influence of hydroxyl-rich guar gum and phosphate moieties resulted in efficient binding of uranium. With a high selectivity towards interfering cations and anions and applicability over a good range of pH, this adsorbent is a promising candidate for uranium remediation from water.

Zirconium Phosphates and Phosphonates: Applications in Catalysis

This review covers recent advancements in the use of zirconium phosphates and phosphonates (ZrPs) as catalysts or catalyst supports for a variety of reactions, including biomass conversion, acid–base catalysis, hydrogenation, oxidation, and C-C coupling reactions, from 2015 to the present. The discussion emphasizes the intrinsic catalytic properties of ZrPs, focusing on how surface acidity, hydrophobic/hydrophilic balance, textural properties, and particle morphology influence their catalytic performance across various reactions. Additionally, this review thoroughly examines the use of ZrPs as supports for catalytic species, ranging from organometallic complexes and metal ions to noble metals and metal oxide nanoparticles. In these applications, ZrPs not only enhance the dispersion and stabilization of active catalytic species but also facilitate their recovery and reuse due to their robust immobilization on the solid support. This dual functionality underscores the importance of ZrPs in promoting efficient, selective, and sustainable catalytic processes, making them essential to the advancement of green chemistry.

Long-term corrosion protection of reinforcing bars via a self-responsive coating incorporating ZrP functional fillers

The conventional coating of reinforcing bars exhibits inadequate anti-corrosion efficacy stemming from a non-specific, blind protection mechanism, poses a threat to the durability of concrete. We devised a novel self-responsive functional filler, L-arginine (LA) intercalated zirconium phosphate (LCZrP), synthesized via an intercalation reaction. This innovative filler was seamlessly integrated into an epoxy (EP) resin matrix, yielding a smart anticorrosive coating that harmoniously combines active and passive corrosion protection strategies. The integration of LCZrP within the coating matrix serves a trifecta of purposes: it extends the corrosion propagation path, effectively disperses nanofiller agglomeration, and enhances interfacial adhesion with the epoxy coating. Critically, the controlled release of corrosion inhibitors from the interlayer further fortifies the coating's resistance to corrosion, imparting a multi-layered protective shield. After enduring a 60-day immersion in a simulated concrete pore solution, the LCZrP/EP coating demonstrated exceptional durability, maintaining a low-frequency impedance modulus value consistently within the range of 4.27×1010 to 5.12×1010 Ω·cm2, marking a remarkable 34-fold enhancement over the performance of the epoxy coating alone. This breakthrough underscores the LCZrP/EP coating's potential as a groundbreaking solution for reinforcing bar protection in concrete, harnessing the complementary strengths of epoxy resin's physical barrier, the impermeability of two-dimensional lamellar structures, and the proactive release of corrosion inhibitors to forge a robust, multi-faceted passivation layer.

Preparation of zirconium hydrogen phosphate coatings on alkali thermal titanium via a one-step sol–gel method to improve the friction resistance, bioactivity, and osteogenic potential

Titanium implants are widely used in dental restorations for patients suffering from dentition defects. However, the biologically inert of Ti, poor osteoinduction properties and the release of Ti particles due to friction between the bone and the implants can inhibit osseointegration and adversely affect the success rate of implantation. In this study, a zirconium phosphate (ZrP) coating was constructed on the surface of alkali thermal titanium (AT-Ti) via a one-step sol–gel approach. Subsequently, the friction resistance, bioactivity, and osteogenesis properties of the prepared coating were studied. The surface characterization results confirmed that AT-Ti was successfully coated with amorphous ZrP, and ZrP modification was found to effectively reduce the friction rate. In addition, the surface morphology after friction test was smoother. In terms of the bioactivity, the presence of a phosphate group in the ZrP coating led to the effective enrichment of Ca2+ to promote the formation of hydroxyapatite (HAp). It was also discovered that ZrP exhibited an excellent performance in cell viability and mineralization experiments, in addition to up-regulating the expression of osteogenesis related genes. Overall, ZrP modification of AT-Ti leads to an excellent friction resistance, bioactivity, and osteoinductive properties, thereby indicating its broad application prospects in implant therapy.

Fabrication of Novel Polyurethane matrix-based Functional Composites with Enhanced Mechanical Performance

Thermoplastic polyurethane (TPU) has gained significant interest in several fields, including automobile steering wheels, and the electronics sector due to their easier processability, abrasive resistance, and self-lubricating performances. However, their strong inherent flammability and significant smoke and heat production during burning limit their industrial applications. Therefore, its applicability can be enhanced with the addition of high-strength reinforcement and making them antibacterial and flame-retardant. This research is designed to examine the influence of zirconium phosphate (ZrP) and zinc oxide (ZnO) nanoparticles on the novel polyurethane/glass fiber reinforced composites for flame retardant and antibacterial applications with improved mechanical performance. Three different types of novel polyurethane (PU1, PU2, PU3) matrices were prepared using different recipes, and 7% ZrP and 5% ZnO nanoparticles were added to the polyurethane matrices separately, and their corresponding composite samples were fabricated using glass reinforcement. Mechanical i.e., Charpy impact, hardness and tensile, and functional i.e., flame retardancy (FR) and antibacterial tests were performed to compare their performance. Mechanical testing results showed that PU3-based composite samples showed the highest values of impact force, hardness, and tensile strength in both ZrP and ZnO nanoparticle-based composite samples. Furthermore, 7% ZrP-PU3 composite exhibited the best performance of flame retardancy due to the presence of hexamethylene diisocyanates (HDI) content. Likewise, the 5% ZnO-PU3-based composite exhibited the highest antibacterial activity along with enhanced mechanical performance.

U(Ⅵ) sorption by porous sodium zirconium phosphate pellets from aqueous solution

Zirconium phosphate is the first artificially produced layered phosphate that can sorb a variety of nuclides from solutions. Sodium zirconium phosphate (NZP) was a type of α-zirconium phosphate (α-ZrP). The porous sodium zirconium phosphate pellets (p-NZP-P) with a diameter of more than ∼3 mm were prepared and used for uranium sorption. The p-NZP-P could be immersed in solutions for more than 5 days without dissolving and structurally collapsing. The sorption properties of U(Ⅵ) on p-NZP-P in solutions were investigated by both static and dynamic sorption tests. Synthetic p-NZP-P was analyzed in detail using various characterizations to investigate their character and structural changes. In the static sorption experiment, the equilibrium sorption capacity reached the 77.5 ± 1.5 mg·g−1 when the initial concentration of U(Ⅵ) was 100 mg/L, pHinitial = 4.5, T = 25 ℃. Uranium sorption increased by ∼69 % and ∼215 %, respectively, when the initial uranium concentration was increased from 100 to 300 mg·L−1 and the temperature was increased from 15 to 55 °C. Furthermore, uranium sorption increased by ∼541 % when the initial pH increased from 2.5 to 4.5, while it decreased by ∼39 % when the initial pH increased from 4.5 to 7.0. The sorption data corresponded to the pseudo-second-order kinetic model and the Langmuir isotherm model, as well as the theoretically predicted value of sorption capacity (∼199.9 mg·g−1). The results of the dynamic sorption experiment showed that decreasing the quality, increasing the flow rate and the initial U(Ⅵ) concentration would shorten the breakthrough time. The dynamic sorption data agreed well with the Thomas model. The characterization confirmed the porous properties, while the U(Ⅵ) sorption mechanisms relate to –OH coordination and ion exchange. A radioactive rare earth wastewater treatment test suggested that p-NZP-P could be the potential uranium sorbent due to its good stability and efficiency. This paper opened opportunities for the development of practical materials for treating radioactive wastewater in the application of actual scenarios.

Morphological, Thermal, and Mechanical Assessment of Polypropylene and Ammonium Phosphate Composites Enhanced with Lignosulfonate and Zirconium.

Polypropylene and ammonium phosphate (AP) composites were synthesized at a 25 wt% concentration. The changes in the morphological, thermal, and physical behavior of the composites were analyzed with the addition of lignosulfonate (LG) and zirconium phosphate (ZrP). Additionally, metallic zirconium was deposited onto lignosulfonate using the magnetron sputtering technique to develop polypropylene and zirconium-modified lignosulfonate (LGMod) composites. Thus, composites of PP/25AP, PP/25AP/8LG/5ZrP, and PP/25AP/8LGMod were synthesized. The synthesis involved mixing the materials in a Hake mixer, followed by compression molding. The composites were characterized by field emission scanning electron microscopy (SEM-EDS), a thermogravimetric analysis (TGA) with combustion parameters, a vertical burn test (UL-94), a thermal camera, and mechanical properties. All composites achieved a V2 rating according to UL-94 standards. The PP/25AP extinguishes flames more quickly compared to other materials, approximately 99.2% faster than PP and showed the lowest temperature variation and mass loss after burning. The PP/25AP/8LG/5ZrP composite exhibited a 7% higher rigidity and 84.5% better flame retardancy compared to pure PP. Additionally, substituting ZrP with LGMod led to a lower environmental impact and improved thermal properties, despite some mechanical disadvantages.

Intercalation modified nano zirconium phosphate inhibitor for inhibiting coal spontaneous combustion

The synthesis and characterization of a modified zirconium phosphate (MZrP) nano-inhibitor for spontaneous coal combustion inhibition were explored through isooctylamine intercalation. Using oxidation experiment, FTIR and SEM, the variation rules of the characteristic parameters of the different coal samples were investigated. It was observed that MZrP exhibited enhanced dispersion within the coal matrix post-intercalation modification. As the MZrP concentration increased, there was a notable decrease in oxygen consumption rate, gas production concentration, and active group content in the coal, alongside a significant increase in apparent activation energy and inhibition efficacy. This enhanced inhibition is attributed to two primary mechanisms. Firstly, the hydrophilic nature of MZrP allows for its uniform distribution on the coal surface and within internal pores, creating a dense carbonized layer. This layer effectively retains moisture and isolates oxygen, enhancing physical inhibition. Secondly, MZrP inhibitor is thermally decomposed into phosphoric acid and its phosphoric acid derivatives, which can effectively capture the H- and -OH in the coal, and strengthens the inactivation of its reactive free radicals. The optimal inhibition was observed in coal samples treated with 6 wt% MZrP, exhibiting an average inhibition rate of 62.2 %, coupled with the lowest rates of gas production and oxygen consumption.

Effect of Acidulated Phosphate Fluoride Gel on Zirconia Intaglio Surface: An In-Vitro Study

Abstract Aim: To evaluate the micro-shear bond strength (µ-SBS) of resin-modified glass ionomer cement and to assess the chemical and topographical changes in the zirconia fitting surface induced by acidulated phosphate fluoride (APF) gel using scanning electron microscope (SEM) analysis and Fourier transform infrared (FTIR) spectroscopy. Materials and Methods: Thirty-two samples were prepared from two zirconia materials, UPCERA HT White and BruxZir® Solid Zirconia, milled by a computer-aided design/computer-aided manufacturing system. From each zirconia sample, six plates were prepared for FTIR and SEM testing. Following sintering, the samples were divided into control and test groups for each material. The APF gel (1.23%) was applied to the intaglio surface of each test group. To measure the µ-SBS between the zirconia materials and luting cement, 20 rectangular samples of zirconia material were prepared. Ten samples were obtained from Upcera and ten from Bruxzir, with five assigned to the control and five to APF groups. Statistical Analysis: For the µ-SBS test, independent samples t test was conducted to determine the level of significance between the tested groups. Results: FTIR spectroscopy revealed new bands for Upcera and Bruxzir zirconia owing to ion exchange between the formed sodium phosphate and the zirconia surface and the formation of zirconium phosphate by an ester reaction. SEM assessment identified lines, scratches, or surface dissociation that appeared on the intaglio–zirconia surface after conditioning. The µ-SBS test, as indicated by the independent samples t test, showed a significant increase in bond strength of 1.266 and 1.566 MPa for Upcera and Bruxzir zirconia, respectively. Conclusion: This study offers new practical, cost-effective, and accurate tests to enhance the µ-SBS of luting cement to yttria-stabilized tetragonal zirconia polycrystal ceramics.

Catalytic recycling of polylactic acid over zirconium phosphate supported WOx active sites

Chemical upcycling of end-of-life plastics is an economically and environmentally feasible way to tackle plastics crisis. Among them, methanol alcoholysis of polylactic acid (PLA) is a promising approach, which can produce methyl lactate (MLA) that can be further converted to lactide to achieve a sustainable development. In this work, a series of WOx/ZrP catalysts with WOx active sites in low coverage and high surface area were synthesized via anchoring WOx species on the surface of zirconium phosphate (ZrP). Characterizations indicated that the strong interaction between WOx and ZrP promoted the formation of WOx active sites in low coverage. In particular, 10 %WOx/ZrP catalyst was highly active and stable for the alcoholysis of PLA plastics under mild conditions due to the abundant WOx active sites and strong acidity. The yield of MLA over 10 %WOx/ZrP catalyst reached 94.5 % within 4 h at 160 °C, which was superior to the performance of traditional solid acids (α-ZrP, HZSM-5, Hβ and Amberlyst-45). In addition, 10 %WOx/ZrP was versatile for the alcoholysis of discarded PLA-based products and could be recycled at least five times. The prominent performance of 10 %WOx/ZrP catalyst and the possible reaction mechanism were discussed.

Electrocatalysis for Water Splitting Using Layered Zirconium Phosphate Nanomaterials

We are studying new applications of layered zirconium phosphate (ZrP) inorganic nanomaterials [1]. The θ phase of ZrP can be directly ion-exchanged with metal complexes and catalysts, producing intercalated phases useful for artificial photosynthesis schemes for water splitting, amperometric biosensors, and drug delivery applications. Recently, we have demonstrated improved electrocatalytic activity of ZrP nanomaterials loaded with metal ions suitable for the oxygen evolution reaction of water splitting. Electrocatalysts have been incorporated as intercalated species, surface bound, on exfoliated layers, and on nanoparticles of different morphologies (hexagonal platelets, cubes, rods, and spheres). Single and bimetallic electrocatalysts based on earth-abundant materials have been studied. Reduction in overpotentials and increases in mass activity have been achieved. Mixed metal NiFe-intercalated ZrP electrocatalysts at 90% Fe metal content proved to have superior OER electrocatalytic performance (decreased overpotentials, increased mass activities, reduced Tafel slopes) compared to adsorbed counterparts. We have recently prepared CoFe electrocatalysts systems and again the intercalated bimetallic system is more active than the surface-adsorbed one. We are starting to work also with Mn electrocatalysts. We are exploring OER activities of other mixed-metal catalysts on ZrP, bifunctional catalysts, and operando synchrotron X-ray absorption spectroscopy studies to elucidate the nature of the active species. We are also exploring efficient solar H2 production using these supports.Reference[1] M. V. Ramos-Garcés; J. González-Villegas; A. López-Cubero; J. L. Colón, Acc. Mater. Res. 2021, 2, 793-803. DOI: 10.1021/accountsmr.1c00102.

Zirconium Phosphate-Pillared Zeolite MCM-36 for Green Production of γ-Valerolactone from Levulinic Acid via Catalytic Transfer Hydrogenation.

γ-valerolactone (GVL), derived from biomass, is a crucial platform compound for biofuel synthesis and various industrial applications. Current methods for synthesizing GVL involve expensive catalysts and high-pressure hydrogen, prompting the search for greener alternatives. This study focuses on a novel zirconium phosphate (ZrP)-pillared zeolite MCM-36 derivative catalyst for converting levulinic acid (LA) to GVL using alcohol as a hydrogen source. The incorporation of ZrP significantly contributes to mesoporosity and greatly enhances the acidity of the catalysts. Additionally, we employed 31P MAS NMR to comprehensively investigate the influence of phosphorus species on both the acidity and the catalytic conversion of LA to GVL. By adjusting the Zr-to-P ratios, we synthesized catalysts with enhanced acidity, achieving high conversion of LA and selectivity for GVL. The catalyst exhibited high recyclability, showing only minor deactivation over the course of five cycles. Furthermore, the catalyst was successfully applied to the one-pot conversion of furfural to GVL, showcasing its versatility in biomass conversion. This study highlights the potential of the MCM-ZrP1 catalyst for sustainable biomass conversion and offers insights for future research in renewable energy technologies.

Removal of anionic dye from textile effluent using zirconium phosphate loaded polyaniline-graphene oxide composite: Lab to pilot scale evaluation

Efficient filtering of dyes is essential for the protection of ecosystem and human health due to the considerable water pollution caused by the effluents released from the sector. We present a simple, scalable UV radiation-assisted method for treating methyl orange dye-polluted water from the textile industry using zirconium phosphate-loaded polyaniline-graphene oxide (PGZrP) composite. The new material was synthesized by sonochemically incorporating a polyaniline-graphene oxide composite with hydrothermally synthesized zirconium phosphate. The efficacy of PGZrP in eliminating methyl orange was evaluated using experimental conditions, and the adsorption capacity was investigated as a function of pH, temperature, adsorbent dosage, and adsorption period. The system follows Langmuir adsorption isotherm with pseudo-second-order kinetics. Thermodynamics studies showed that enthalpy (H°) and entropy (S°) values are positive, indicating that the dye adsorption increases with increasing temperature and is an endothermic reaction. The maximum adsorption capacity was found to be 36.45379 mg/g for methyl orange. Using the COMSOL Multiphysics CFD Platform, an attempt was made to check the temperature and concentration profile of a PGZrP composite in a real industrial system. The predicted result shows that there is no significant temperature change in the material during the adsorption process and the concentration of dye is mainly located on the top region of the bed. The developed zirconium phosphate decorated polyaniline-graphene oxide composite can be successfully utilized for the effective removal of methyl orange from industrial wastewater in bulk quantity which is coming from the textile industry, and the composite can be reused for several cycles with good efficiency. In this work, we have designed a miniaturized proof of concept to remove methyl orange from water which showed good dye removal efficiency.

Novel electrochemical sensor based on zirconium phosphate phosphidation for detection of Asulam

Novel electrochemical sensor based on zirconium phosphate phosphidation for detection of Asulam

Preparation, Characterization of Zirconium Phosphate Composites and Their Adsorption Properties of Phenolic Wastewater

Preparation, Characterization of Zirconium Phosphate Composites and Their Adsorption Properties of Phenolic Wastewater

Thermal Vapor Deposition of a Hydrophobic and Gas-Permeable Membrane on Zirconium Phosphate Cation Exchanger: An Oral Sorbent for the Urea Removal of Kidney Failure.

An oral sorbent with high capacity for NH4+ is desirable in lowering the blood urea level and mitigating the dialysis burden for end-stage kidney disease (ESKD) patients. Zirconium phosphate (ZrP) is an amorphous cation ion exchanger with high NH4+ binding capacity as a sorbent material, but its selectivity to remove NH4+ is limited in the presence of other competing ions in water solution. We previously have developed a gas-permeable and hydrophobic perfluorocarbon coating on ZrP, which improves ZrP's NH4+ selectivity. However, the coating preparation procedure, a wet chemistry approach, is complicated and time-consuming, and more importantly, the large amount of usage of acetone poses a concern for the application of ZrP as an oral sorbent. In this study, we developed a solventless coating protocol that effectively coats ZrP with tetraethyl orthosilicate (TEOS) and 1H,1H,2H,2H-perfluorooctyltriethoxysilane (FOTS) via thermal vapor deposition (TVD) in a simplified manner. X-ray photoelectron spectroscopy (XPS) and contact angle measurements verify the two coatings are successfully deposited on the ZrP surface, and the coating condition was optimized based on an in vitro static binding study. The dynamic binding study of competing ions on Na-loaded ZrP with TVD coatings yields a maximum NH4+ removal (∼3.2 mequiv/g), which can be improved to ∼4.7 mequiv/g if H-loaded ZrP under the same coating condition is used in basic stock solutions. More importantly, both materials barely remove Ca2+ and show excellent acid resistance. The significant improvement in the NH4+ binding capacity and selectivity reported here establishes a highly promising surface modification approach to optimize oral sorbents for ESKD patients.

Bifunctional Zirconium Phosphate with Greigite for Electrochemical Detection and Simultaneous Removal of Heavy Metal Ions and Nitro Compounds.

Electrochemical sensing is emerging as a method of choice for the sensing and monitoring of contaminants in water. Various sensing platforms have been designed for sensing heavy metal ions and organic pollutants in water bodies. Herein, we report a new electrochemical platform that can be used for the detection of both heavy metal ions and nitro-based organic contaminants in water bodies. The electrochemical sensor uses a modified electrode based on Fe3S4-impregnated zirconium phosphate (ZrP) nanoparticles synthesized by a simple ultrasonication method. The ZrP@Fe3S4 nanoparticles were thoroughly characterized by power X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX), and ζ-potential studies. The material exhibits an excellent electrochemical performance for the detection of Pb2+, Hg2+, nitrophenol, nitroaniline, and picric acid with low limits of detection of ca. 0.93, 0.70, 0.98, 1.10, and 1.53 ppm, respectively. Since ZrP@Fe3S4 nanoparticles are magnetically recyclable, their adsorption capacity and recyclability have been thoroughly investigated for the uptake of Pb2+ and Hg2+ ions from contaminated water. We observed that the adsorption of Pb2+ and Hg2+ ions on ZrP@Fe3S4 is best described by the Langmuir isotherm and pseudo-second-order kinetic models, with adsorption capacities of 219.44 and 118.4 mg/g, respectively. Similarly, the removal efficiency of ZrP@Fe3S4 was found to be 91, 57.6, and 31.3% for nitrophenol, nitroaniline, and picric acid, respectively. Furthermore, the theoretical calculations using density functional theory (DFT) were carried out to find the adsorption energy, affinity, and point of adsorption, which are in line with the experimental results. DFT calculations further suggest that the incorporation of Fe3S4 on ZrP improves the surface charge density and promotes efficient electron transfer between the electrode and the analyte. We have shown the real-time analysis of Dal lake water as a proof of concept, and the synthesized composite exhibits good recovery and promising results for metal ion sensing. ZrP@Fe3S4 demonstrated an excellent cycling stability and long-term stability without noticeable degradation for 1 week.

Novel zirconium phosphate/MXene/ionic liquid membranes for PEM fuel cells operating up to 145°C

In this work, zirconium phosphate, MXene, and a hexyl-based ionic liquid were incorporated into a porous PTFE polymer to synthesize novel composite proton exchange membranes (PEM) for fuel cell applications. The synthesized composite membranes were evaluated for their conductivity at temperatures above the boiling point of water as well as their water uptake properties, thermal stability, surface morphology, and structural characteristics via several characterization techniques. It was observed that the inclusion of MXene had a direct impact on the thermal stability of these membranes and caused substantial structural modifications within the membrane’s matrix. The fabricated membranes displayed a high proton conductivity at room temperature, reaching a peak of approximately 10−2 S/cm when all materials were combined. The membranes exhibited good proton conductivity of 10−4 S/cm at high temperature ranges up to 145℃ and appeared to be stable at higher temperatures, as thermogravimetric analyses showed. The results reported here demonstrate the suitability of the MXene-based synthesized membranes for hydrogen-fueled PEM fuel cell applications. This, in turn, will contribute to enhanced energy efficiency and cleaner energy transition.

Th(IV) adsorption by heulandite–high-temperature activated sodium zirconium phosphate from aqueous solution

Herein, heulandite–high-temperature activated sodium zirconium phosphate (HEU–HTA-Na-ZrP) composites were first synthesised for adsorbing tetravalent thorium (Th(IV)) from aqueous solution. Furthermore, the HEU–HTA-Na-ZrP pellets (HEU–HTA-Na-ZrP-P) were fabricated for dynamic adsorption. Compared to Na-ZrP, the BET surface area of HEU–HTA-Na-ZrP increased of ∼ 189 m2⋅g−1. In batch adsorption, Th(IV) adsorption increased with increasing pH, C0 values (initial concentrations) and temperature. The equilibrium Th(IV) adsorption capacities were 314.17 ± 11.27 mg⋅g−1 and 358.89 ± 3.47 mg⋅g−1 for Na-ZrP and HEU–HTA-Na-ZrP, respectively. Thermodynamics, isotherms and kinetics suggested an endothermic, spontaneous, homogeneous and chemisorption process. Characterization verified the adsorption capacities of Th(IV), and the main possible Th(IV) adsorption mechanisms were associated with ion exchange and –OH, Zr–O coordination. Notably, the reusability study indicated that the samples treated with 0.1 mol⋅L−1 H3PO4 solution exhibited excellent reusability. Dynamic adsorption results indicated the structural stability of the composite pellets. 50% Th(IV) breakthrough time (τ (min)) increased with increasing mass and then decreased, and τ (min) decreased with increasing pH. Both Thomas and Yoon–Nelson models could better describe the Th(IV) dynamic adsorption behaviour. Moreover, HEU–HTA-Na-ZrP-P could separate Th(IV) from simulated and real nuclear wastewater. This work demonstrates that HEU–HTA-Na-ZrP can be applied as an efficient adsorbent for the removal of Th(IV) from Th-containing solutions.