Metaphosphate Research Articles

VPO4F Fluorophosphates Polyanion Cathodes for High‐Voltage Proton Storage

AbstractProton batteries are emerging in electrochemical energy storage because of the associated fast kinetics, low cost and high safety. However, their development is hindered by the relatively low energy density due to the limited choice of cathode materials. Herein, metal phosphate polyanion cathodes are proposed as the proton cathode for the first time. Combining experimental results and theoretical simulations, a universal criterion for the proton cathode was put forward. Vanadium fluorophosphate (VPO4F) was demonstrated as a promising high‐voltage proton cathode material with a specific capacity of 116 mAh g−1 at a high potential of 1.0 V (vs. SHE). The proton insertion/extraction mechanism in the VPO4F electrode was also verified through X‐ray diffraction (XRD) and photoelectron spectroscopy (XPS). Furthermore, the stability of VPO4F was investigated in various electrolytes and the optimized electrolyte enabled the stable operation of VPO4F for 300 cycles. This work provides new inspiration in the exploitation of new electrode materials for electrochemical proton storage devices.

VPO4 F Fluorophosphates Polyanion Cathodes for High-Voltage Proton Storage.

Proton batteries are emerging in electrochemical energy storage because of the associated fast kinetics, low cost and high safety. However, their development is hindered by the relatively low energy density due to the limited choice of cathode materials. Herein, metal phosphate polyanion cathodes are proposed as the proton cathode for the first time. Combining experimental results and theoretical simulations, a universal criterion for the proton cathode was put forward. Vanadium fluorophosphate (VPO4 F) was demonstrated as a promising high-voltage proton cathode material with a specific capacity of 116 mAh g-1 at a high potential of 1.0 V (vs. SHE). The proton insertion/extraction mechanism in the VPO4 F electrode was also verified through X-ray diffraction (XRD) and photoelectron spectroscopy (XPS). Furthermore, the stability of VPO4 F was investigated in various electrolytes and the optimized electrolyte enabled the stable operation of VPO4 F for 300 cycles. This work provides new inspiration in the exploitation of new electrode materials for electrochemical proton storage devices.

Ni- and Co-Struvites: Revealing Crystallization Mechanisms and Crystal Engineering toward Applicational Use of Transition Metal Phosphates

Ni- and Co-Struvites: Revealing Crystallization Mechanisms and Crystal Engineering toward Applicational Use of Transition Metal Phosphates

Short Communication: Metabolites of Albizia inhibit in vitro growth of phosphate solubilizing microbial consortia isolated from tea garden soil of Darjeeling hills, India

Abstract. Saha S, Ghosh A, Acharyya S, Bhattacharya M. 2022. Short Communication: Metabolites of Albizia inhibit in vitro growth of phosphate solubilizing microbial consortia isolated from tea garden soil of Darjeeling hills, India. Biodiversitas 23: 2865-2870. Phosphate solubilizing microorganisms (PSM) play a crucial role in maintaining the nutritional status and fertility of the soil. PSMs help in solubilizing the metallic phosphate salts of soil into available phosphate anions for easy uptake by plants. However, this beneficial group of microorganisms also face different challenges for survival from its immediate surroundings. This study was carried out to assess the effect of shade tree litters on the PSM consortia isolated from different tea garden soils of Darjeeling hills, since shade trees are an integral part of tea plantations. Albizia odoratissima, Albizia chinensis and Albizia procera, widely used in tea gardens as shade trees were selected. GC-MS analysis was carried out to detect the metabolites produced by the litters. Twenty-three compounds exhibiting antimicrobial activities were detected. Major peak was found in A. odoratissima, followed by A. chinensisand least in A. procera. Compounds like 1-heptanol, 2-propyl-, neophytadiene, phytol and squalene were common in all three extracts and are considered to provided antimicrobial activity to Albizia. A proportional relation has been observed between magnitude of inhibition zones and peak area percentage in Albizia spp. PSM isolates from shade tree gardens were observed to be more tolerant toward the leaf extracts.

Hydrothermally synthesized nickel copper phosphate thin film cathodes for high-performance hybrid supercapacitor devices

Transition metal phosphate (TMP) based materials are developing as advanced type electrode materials for hybrid supercapacitors (SCs) due to their unprecedented conductivity, and rich redox activity. Attracted by these fabulous physicochemical characteristics of metal phosphates, binder-free nickel copper (Ni-Cu) phosphate thin films directly grown on stainless steel (SS) substrate by hydrothermal method. The morphological alteration from microplates like nickel phosphate to microrods like copper phosphate is detected with increasing copper content in Ni-Cu phosphate thin films. The optimal 1:1 ratio of nickel and copper in Ni-Cu phosphate (Ni1.62Cu1.35(PO4)2·H2O) thin film illustrates high specific capacitance (Cs) (capacity (Cc)) of 711 F g−1 (355.5 C g−1) at 1.5 A g−1. More significantly, a hybrid aqueous SC (HASC) and all-solid-state SC (HASSC) electrochemical energy storage devices (ESDs) have been fabricated. The HASC device showed superior Cs (85 F g−1 at 0.8 A g−1) with specific energy (SE) of 30 Wh kg−1 at 1.27 kW kg−1 specific power (SP). Additionally, HASSC device offers a higher Cs (52 F g−1 at 0.6 A g−1) with 18.53 Wh kg−1 SE at 1.64 kW kg−1 SP. Also, both HASC and HASSC devices exhibit excellent long-term durability of 84.81 and 80.83 %, respectively, after 5000 GCD cycles. Moreover, HASSC device brightens a panel of 201 red light-emitting diodes (LEDs) illustrating its commercial practicability to next-generation hybrid energy storage devices.

Solvent-Free Green Synthesis of Cu0.5Ti2(PO4)3 and Cu0.5TiO(PO4) NASICON-Type Compounds from Ilmenite Mineral Sand

Ilmenite is a naturally available black or steel-gray color mineral, called titanium iron oxide, FeTiO3.This valuable mineral comprises a significant amount of titanium that can be utilized as a titanium source to synthesize various materials. This study focused on synthesizing copper titanium phosphate compounds via an eco-friendly solid-state reaction route. α-titanium bismonohydrogen orthophosphate monohydrate (α-Ti(HPO4)2.H2O/α-TiP), derived from beach sand ilmenite used as the starting material for the synthesis. α-TiP was obtained by digesting ilmenite with 85 wt% phosphoric acid under reflux conditions. The XRD pattern of the obtained white powder confirmed the formation of α-TiP. The synthesized α-TiP and copper (Ⅱ) acetate were ground with different molar ratios (1:2, 1:1, and 2:1) until it forms a fine powder following a solvent-free solid grinding method. These powder mixtures were calcined at 800 °C for 4 hours utilizing a muffle furnace. The obtained solid solutions developed green and two different shades of yellow color. The samples werecharacterized by XRD, Thermogravimetry (DSC/TGA) techniques, and Raman spectroscopy. The XRD results revealed the formation of solid solutions containing copper titanium phosphate (Cu0.5Ti2(PO4)3) at 1:1 and 2:1 molar ratios of α-TiP to copper (Ⅱ) acetate while the products obtained at 1:2 and 1:1 molar ratios confirmed the formation of copper titanium oxyphosphate (Cu0.5TiOPO4). Moreover, TGA results confirm the development of these mixed metal phosphates which can be further analyzed for applications in the ceramic industry. Therefore, calcination of the reaction mixtures by changing the molar ratios produced different colored stable compounds that can potentially be used as ceramic pigments, coatings, and electrode materials.
 Keywords: Copper titanium phosphate, α-titanium bismonohydrogen orthophosphate monohydrate, Solid-state reaction route

Simultaneous Incorporation of V and Mn Element into Polyanionic NASICON for High Energy‐Density and Long‐Lifespan Zn‐Ion Storage (Adv. Energy Mater. 23/2022)

Aqueous Zinc-ion Batteries In article number 2200654, Linfeng Hu and co-workers develop NASICON-typed V-Mn transition metal phosphate, Na4VMn(PO4)3, as a cathode material for robust aqueous Zn-ion storage. Taking advantage of its high-voltage properties that originate from the inductive effect and two-step electron transfer mechanism between V4+/V3+ and Mn3+/Mn2+ redox couple, the Na4VMn(PO4)3 cathode exhibits excellent overall battery performance with an energy density of 309.7 Wh kg−1, and good rate capacity and cycling stability (89.1% capacity retention after 3000 cycles).

Phase Evolution and Li Diffusion in LATP Solid‐State Electrolyte Synthesized via a Direct Heat‐Cycling Method

Herein, the direct synthesis of phase‐pure lithium aluminum titanium phosphate (Li1.3Al0.3Ti1.7(PO4)3, LATP) solid‐electrolyte powder in 220 min and relatively low temperatures (850 °C) is achieved via a new (cyclic) fast heat treatment (c‐FHT) route. The complex structural evolution highlights rate‐limited lithium incorporation of intermediate metal phosphates formed prior to the final phase‐pure LATP. The prepared LATP product powder displays similar bulk (2 × 10−10 cm2 s−1) and local (3 × 10−10 cm2 s−1) values for lithium diffusion coefficients (DLi) characterized by electrochemical impedance spectroscopy and muon spin relaxation (μSR), respectively. The similarity between both DLi values suggests excellent retention of inter‐ and intraparticle lithium diffusion, which is attributed to the absence of deleterious surface impurities such as AlPO4. A low‐energy barrier (Ea = 73 meV) of lithium diffusion is also estimated from the μSR data.

Stabilization of immobilized lipases by treatment with metallic phosphate salts

Lipases from Thermomyces lanuginosus (TLL), Rhizomucor miehei (RML), Candida rugosa (CRL), forms A and B of lipase from Candida antarctica (CALA and CALB) and Eversa Transform 2.0 have been immobilized on octyl-agarose beads at two different loads (1 mg/g and saturated support) and treated with phosphate and/or some metallic salts (Zn2+, Co2+, Cu2+). They have been also immobilized on the support modified by the metallic phosphate, usually driving to biocatalyst with lower stability or marginal improvements. The effects of the phosphate/metal modification on enzyme features depended on the loading of the support. Some enzymes (TLL, CRL or CALA), mainly using the highly loaded biocatalysts, showed very significant improvement on enzyme stability after the treatment with some of the metal phosphates (next to a 20-fold factor), improvements that were not justified by the presence of metallic or phosphate ions in solution, as they had negative effects on enzyme stabilities. In some other cases, a significant increase in enzyme activity was detected (e.g., CALB). This could be explained by the modification of the nucleation places of the enzymes by the metallic phosphate, and this could help to explain the good results obtained in the nanoflower immobilization of many enzymes.

High performance composite films assembled on metal substrates with graphene oxide

Friction and wear seriously affect the performance, service life and stability of metal moving parts. In this work, a novel GO composite film grafted with POCl3 was fabricated on metal substrates, including SS, Ti and Al. These films showed excellent tribological properties, including high carrying capacity, low friction coefficient (COF) and low wear volume on the macroscale. A tribofilm composed of GO nanoflakes and metallic phosphate was formed in the wear track of SS substrate. In addition, amorphous carbon and metallic phosphate were the main components of the transfer layer formed on the surface of the steel ball. The excellent tribological properties were dominated by GO, and the great wear resistance was attributed to the formation of metallic phosphates during the friction process. Simulation results showed that the oxygen of metallic phosphate was derived from GO modified with POCl3 rather than air. Taking the synergistic effect of GO and POCl3 into account when designing nanocomposite films is of great value in industrial applications.

Effect of leaching pretreatment on the inhibition of slagging/sintering of aquatic biomass: Ash transformation behavior based on experimental and equilibrium evaluation

In this study, aquatic biomasses of Ulva lactuca and Hydrilla verticillata were pretreated by water and acid washing. A comprehensive assessment strategy, including systematic experiments and equilibrium calculations, was used to study the migration of elements and transformation characteristics of minerals in aquatic biomass ash before and after leaching pre-treatment. The effect of leaching pre-treatment on slagging inhibition was analyzed. Owing to the different mineral compositions and characteristics of the two types of aquatic biomass, the serious slagging caused by Ulva lactuca was related to the presence of alkali (Na and K) sulfate. In contrast, the presence of silicate/aluminosilicates in Hydrilla verticillata had a greater effect on slagging. The removal of alkali metals (especially Na and K) and Cl from aquatic biomass by leaching pretreatment was conducive to alleviating aquatic biomass slagging. Following leaching pretreatment, the alkali index of the aquatic biomass was reduced to <0.17, and the Cl content was reduced to <0.3%. Furthermore, the abundant alkaline earth metals (Ca and Mg) in aquatic biomass can inhibit slagging by generating high-melting-point alkaline earth metal silicates or phosphates. The removal rate of alkaline earth metal oxides by acid washing was >96% and >78% in Ulva lactuca and Hydrilla verticillata, respectively, while water washing was less effective. Although water and acid washing can alleviate slagging, a comparative investigation showed that water washing of aquatic biomass had better outcomes than acid washing. Therefore, water washing is a better way to comprehensively pre-treat aquatic biomass. The results obtained can help promote the thermochemical utilization of aquatic biomass on an industrial scale.

Genuine Pores in a Stable Zinc Phosphite for High H2 Adsorption and CO2 Capture.

An uncommon example of stable mixed-ligand zinc phosphite with genuine pores has been synthesized by using zinc metal, inorganic phosphite acid, thio-functionalized O-donor (2,5-thiophenedicarboxylate, TPDC), and tetradentate N-donor [1,2,4,5-tetrakis(imidazol-1-ylmethyl)benzene, TIMB] units assembled into one crystalline structure according to a hydro(solvo)thermal method. This is a very rare case of a metal phosphite incorporating both N- and O-donor ligands. The tetradentate TIMB linker bound to zinc atoms of the isolated zincophosphite hexamers to form a 3D open-framework structure by crosslinking structural components of 1D chains and 2D layers. Here, the TPDC ligand acts as a monodentate binding model to functionalize its porous structure with the uncoordinated S atom and COO- group. Interestingly, this compound demonstrates the highest H2 storage capacity among organic-inorganic hybrid metal phosphates (and phosphites), and a good CO2 capture at 298 K compared with the majority of crystalline materials. The possible adsorption sites and selectivity for CO2 over H2 , N2 , and CO at 298 K were calculated by using density functional theory (DFT), the ideal adsorption solution theory (IAST), and fitting experimental pure-component adsorption data.

Uncommon 3D Twofold Interpenetrated Zinc Phosphate Consisting of Inorganic Chains and Mixed Ligands for Highly Efficient Dye Removal Ability Using Its Nanosized Particles.

The flexible blocks are the primary building units for constructing crystalline solids with interpenetrating structures. Herein, we reported a novel class of crystalline material with such structural features, which was made of two tetradentate ligands and one-dimensional (1D) rigid chains of zinc phosphate. This is also the first example of transition metal phosphate incorporating a squarate linker. Furthermore, efficient dye removal ability has been presented.

Cobalt manganese phosphate and sulfide electrode materials for potential applications of battery-supercapacitor hybrid devices

Electrode materials with efficient electrochemical properties are always desirable for high storage energy devices. Here, due to the attractive attributes of metal phosphates and sulfides, we present a sonochemically synthesized binary composite of cobalt manganese phosphate (CoMn(PO4)2) and sulfide (CoMnS) for the real-world applications. The surface and structural properties of the synthesized materials are then investigated through X-ray diffraction (XRD) and scanning electron microscopy (SEM). Subsequently, the prepared electrode materials are optimized through electrochemical measurements performed in a three-electrode assembly. The best performing electrode, (CoMnS (S2) yielding a specific capacity (Qs) of 537 C/g at a current density js of 1 A/g) is then amalgamated with a carbonaceous electrode (activated carbon AC) for the fabrication of asymmetric (supercapattery) device. The constructed device (S2//AC) is then subjected to a two-electrode setup, providing an outstanding specific energy (Es) of 73.52 Wh/kg and a maximum specific power (Ps) of 10,200 W/kg. Afterwards, the device is analyzed for a stability test and preserved a maximum capacity retention of 90.03% against 10 A/g for 10,000 charge-discharge cycles. A semi-empirical approach via Dunn's model is next exploited to scrutinize the negative (capacitive) and positive (diffusive) electrode contributions for the device.

Effect of electroless plating time and temperature on the formation and antibacterial ability of Cu-plated cement-based material

Microbial induced corrosion (MIC) is an increasing challenge in concrete wastewater conveyance systems. Preventing MIC usually requires a corrosion-resistant chemical/antibacterial coating on cement-based materials. This study investigated the effects of electroless plating time and temperature on the preparation of the Cu-plated hardened cement paste (HCP) and successfully applied electroless copper plating to modify the HCP surface for antibacterial properties. The results indicated that the main components of the coating were metallic copper nanoparticles and phosphate sediment. The HCP plated for 4 h resulted in a relatively higher mass gain (0.76%) and Vickers hardness (163.6 HV). 65 °C was more favorable for reaction kinetics, displaying better mass gain and Vickers hardness. Besides, the antibacterial assays and accelerated bio-corrosion experiments indicated that the Cu-plated HCP had a significant improvement in the antibacterial performance and MIC resistance. Therefore, the proposed electroless plating process is a viable method for cement-based material to meet the MIC challenge.

Alkali Metal Di-tert-butyl Phosphates: Single-Source Precursors for Homo- and Heterometallic Inorganic Phosphate Materials.

The reaction of alkali metal acetates, M(OAc)·nH2O (M = Li, Na, K), with thermally and hydrolytically unstable di-tert-butylphosphate ((tBuO)2PO2H, dtbp-H) in a 1:1 molar ratio in MeOH at room temperature leads to clean formation of group 1 metal phosphates [Li(μ-dtbp)]n (1), [Na(μ-dtbp)]n (2), and [K4(μ-dtbp)4(μ-H2O)3]n (3). All three compounds are essentially M/L 1:1 complexes. Owing to the presence of larger potassium ions, additional coordinated water molecules are found in 3, which has been further employed as a precursor for the synthesis of a mixed-metal phosphate polymer [CaK(μ-H2O)3(μ-dtbp)3]n (4) by reacting 3 with Ca(OAc)2. Compounds 1-4 have been characterized by various analytical and spectroscopic techniques. Molecular structures of 1-4 have been established in the solid state by single-crystal X-ray diffraction studies, which reveal them to be one-dimensional polymers, where the adjacent metal centers are connected through -O-P-O- bridges formed by the dtbp ligand. These complexes are rare examples of analytically pure alkali metal alkyl phosphates bearing no additional N-donor ligands (other than dtbp ligands, only water molecules are coordinated to the metal centers). Therefore, these compounds can be employed as single-source precursors (SSPs) for nano-sized ceramic phosphates. The thermogravimetric analysis of 1-4 reveals the loss of thermally labile tert-butyl substituents of the organophosphate ligands to form organic-free phosphate materials in the temperature range 300-500 °C. Solvothermal decomposition of 1-3 in boiling toluene leads to the formation of corresponding dihydrogen phosphates M(H2PO4) (M = Li, Na, and K). The thermal decomposition of heterometallic 4 in the temperature range 400-800 °C leads to the formation of phase-pure mixed-metal calcium potassium metaphosphate CaK(PO3)3.

Electroreduction: A Sustainable and Less Energy‐Intensive Approach Compared to Chemical Reduction for Phosphine Oxide Recycling to Phosphine

AbstractAlthough phosphate minerals are the only naturally occurring resources of the industrially important element phosphorus,[1,2] the industrial extraction of white phosphorous (P4) from metal phosphates relies on demineralization at high temperatures (ca. 1500 °C) in the presence of coke and it releases large amounts of CO and CO2.[3] Due to wide industrial applications of white phosphorus (P4) as a manufacturing precursor for the production of fertilizers, pesticides, fireworks, and detergents,[1] a rapid shrinking of natural reserves of this mineral is obvious and thereby demands an efficient recycling strategy. Moreover, organophosphines are versatile phosphine donor ligands in the development of transition metal catalysts for the bulk‐scale production of alkenes, functional alcohols, esters, and amines. However, the production of such industrially and commercially important organic compounds is associated with the generation of tons of phosphine oxide per year, a product whose further breakdown is highly energy demanding. This essentially amounts to the need for an economic recycling strategy. At present, lab‐ and/or industrial‐scale recycling of phosphine oxide purely relies on chemical routes using metal hydrides and/or harsh reductive conditions which lead to generation of further reagent wastes. Such harsh reaction conditions and further toxic waste generation demand the development of less energy intensive methods. For the past few years, electro‐reduction of phosphine oxides to phosphines remains a pioneering approach to bypass the energy intensive chemical routes. This review summarizes the fundamental studies on electrochemistry of phosphines and phosphine oxides in 1970–1980s and implementation of such knowledge in the development of successful electro‐deoxygenation of phosphine oxides in recent times. Research outlook and future scope of this newly developing research area have also been discussed.

Zeolitic Imidazolate Framework 67-Derived Ce-Doped CoP@N-Doped Carbon Hollow Polyhedron as High-Performance Anodes for Lithium-Ion Batteries

Zeolitic Imidazolate Framework 67 (ZIF-67) and its derivates have attracted extensive interest for lithium-ion batteries (LIBs). Here, Cerium-doped cobalt phosphide@nitrogen-doped carbon (Ce-doped CoP@NC) with hollow polyhedron structure materials were successfully synthesized via ionic-exchange with Co and Ce ions using the ZIF-67 as a template followed with a facile low-temperature phosphorization treatment. Benefitting from the well-designed hollow polyhedron, steady carbon network, and Ce-doping structural merits, the as-synthesized Ce-doped CoP@NC electrode demonstrated superior performance as the anode in LIBs: a superior cyclability (400 mA h g−1 after 500 cycles) and outstanding rate-capability (590 mA h g−1, reverted to 100 mA g−1). These features not only produced more lithium-active sites for LIBs anode and a shorter Li-ion diffusion pathway to expedite the charge transfer, but also the better tolerance against volume variation of CoP during the repeated lithiation/delithiation process and greater electronic conductivity properties. These results provide a methodology for the design of well-organized ZIFs and rare earth element-doped transition metal phosphate with a hollow polyhedron structure.

Hydrothermal carbonization of corn straw in biogas slurry

Hydrothermal carbonization of corn straw with biogas slurry (HTCBS) was studied, with the goal of recovering nutrients from biogas slurry (BS), producing slow-release fertilizer, and sequestration of CO2. Specifically, the impacts of hydrothermal carbonization temperature (160–280 °C) and solid-to-liquid ratio (S/L) (1:5–1:25) on the characteristics of hydrochar and aqueous phase (AP) were investigated. Under the optimized hydrothermal carbonization condition at 250 °C and 1:10 S/L, total nitrogen, ammonia nitrogen and total phosphorus in AP decreased 30%, 64% and 91%, respectively, where total potassium increased 36% comparing with BS. Compared to traditional two-step hydrothermal carbonization followed by biogas slurry nutrient adsorption, HTCBS process was better suited for nutrient recovery (especially nitrogen and phosphorus) from BS. The proposed mechanism of nitrogen adsorption was the formation of C–N bond, and phosphorus was collected via the generation of metal phosphate precipitates, where potassium was released into AP from corn straw due to the high solubility in water. Additionally, a significant amount of humic substances (45 g/L) was obtained in AP of HTCBS. This study indicated the viability of HTCBS to recover nitrogen and phosphorus from BS, and potentially provide a potassium humate enriched water-soluble fertilizer.

Technique of Phosphorus Recovery from Dehydrated Sludge by Incineration

Water sludge contain significant amounts of phosphorus, and in order to recover the phosphorus, some kinds of methods are investigated. One of the methods, phosphorus recovery from the dehydrated sludge by incineration is considered to be useful. The dehydrated sludge was mixed with the reagent of NaOH, KOH or Na2CO3, and incinerated at 750 °C or 900 °C. Phosphorus in the generated ash of the sludge was dissolved by the addition of the hot water, and recovered by the evaporation of the extract. The recovered phosphorus was confirmed to be an alkali metal phosphate, and the recovery rate reached about 75%.