Valence Of Ions Research Articles

Defects‐Induced Photochromism and Luminescent Modulation Based on Lanthanides‐Doped Cadmium Glass Toward Optical Storage Applications

AbstractOwing to the large storage capacity, the transparent luminescent glass with photo‐induced coloration properties has attracted considerable interest in recent years. However, lots of the photochromic (PC) mechanisms for glass are related to the ionic valence transformation, and the study associated with the defects‐induced photochromism of glass is limited. Herein, a kind of Sm3+ doped PC cadmium glass is fabricated, for which the PC mechanism is systematically investigated by various techniques, such as XPS spectra, thermoluminescence spectra, EPR spectra, etc. The results show that the mechanism of coloration for such glass should be due to the presence of oxygen vacancy‐related electron centers. Under 365 nm light irradiation, the color of the glass turns from colorless to brown, exhibiting a large color contrast, of 62%. Utilizing the re‐absorption process between absorption spectra and emission/excitation spectra, the emission intensity of Sm3+ is reversibly regulated, indicating their promising applications as an optical storage medium.

Unraveling the multi-pollutant removal using M-MoWTi (M = Fe, Mn, Cr) catalyst: experiment and mechanistic study of competition for active sites.

Multi-pollutant removal (MPR) of NO and VOCs simultaneously is efficient of flue gas treatment in coal-fired power plants. But reducing the competition for active sites between NH3, NO, C6H6, and C7H8 remains challenging. Herein, Cr, Mn, and Fe were respectively doped to MoWTi catalyst via wet impregnation. The Fe3+ + Mo5+ ↔ Fe2+ + Mo6+ redox cycle led to an increased proportion of low valence ions (Mo5+ and W5+) and facilitated the creation of active oxygen vacancies with several active sites. It also possessed plentiful mild to strong acid sites with ideal ratio. These factors enhanced catalytic activity of Fe-MoWTi. Remarkable MPR efficiencies of NO, C6H6, and C7H8 were achieved under industrial SCR condition, characterized by low oxygen but high SO2 levels at 340 °C, with removal rates reaching 89.85%, 97.57%, and 86.30% respectively. Theory calculations further revealed that Fe-MoWTi favor NH3 and O2 adsorptions. NO elimination was found to follow both Eley-Rideal (E-R) and Langmuir-Hinshelwood (L-H) processes, supported by in situ DRIFTS analysis. The reactions involving NO/NO2/nitrite/nitrate occurred with NH3(ads)/ NH4+(ads)/NH2 (ads). C6H6 and C7H8 underwent gradual oxidation, formatting alcohols, aldehydes, acids, and maleic acids, before eventually being mineralized to gaseous CO2 and H2O. Findings hold significant potential for application, providing guidance for the development of catalysts with improved resistance against SO2 poisoning and enhanced MPR capabilities.

Molecular interactions of acids and salts with polyampholytes.

The Hofmeister series characterizes the ability of salt anions to precipitate polyampholytes/proteins. However, the variation of protein size in the bulk solution of acids and the effect of salts on the same have not been studied well. In this article, the four acids (CH3COOH, HNO3, H2SO4, andHCl) and their effects on the hydrodynamic radius (RH) of gelatin in the bulk solution are investigated. The effects of Na salt with the same anions are also considered to draw a comparison between the interactions of acids and salts with polyampholytes. It is suggested that the interactions of polyampholytes with acids are different from those of salts. The interaction series of polyampholytes with acids with respect to the RH of the polyampholyte is CH3COO->NO3->Cl->SO42- whereas the interaction series with salts is SO42->CH3COO->Cl->NO3-. These different interactions are due to equilibration between acid dissociation and protonation of polyampholytes. Another important factor contributing to the interactions in weak acids is the fact that undissociated acid hinders the movement of dissociated acid. Experiments and simulations were performed to understand these interactions, and the results were identical in terms of the trend in RH (from the experiments) and the radius of gyration (Rg) (from the simulations). It is concluded that the valence of ions and dissociation affect the interaction in the case of acids. However, the interactions are influenced by the kosmotropic and chaotropic effect, hydration, and mobility in the case of salts.

Unraveling the Role of Solvation and Ion Valency on Redox-Mediated Electrosorption through In Situ Neutron Reflectometry and Ab Initio Molecular Dynamics.

Solvation and ion valency effects on selectivity of metal oxyanions at redox-polymer interfaces are explored through in situ spatial-temporally resolved neutron reflectometry combined with large scale ab initio molecular dynamics. The selectivity of ReO4- vs MoO42- for two redox-metallopolymers, poly(vinyl ferrocene) (PVFc) and poly(3-ferrocenylpropyl methacrylamide) (PFPMAm) is evaluated. PVFc has a higher Re/Mo separation factor compared to PFPMAm at 0.6 V vs Ag/AgCl. In situ techniques show that both PVFc and PFPMAm swell in the presence of ReO4- (having higher solvation with PFPMAm), but do not swell in contact with MoO42-. Ab initio molecular simulations suggest that MoO42- maintains a well-defined double solvation shell compared to ReO4-. The more loosely solvated anion (ReO4-) is preferably adsorbed by the more hydrophobic redox polymer (PVFc), and electrostatic cross-linking driven by divalent anionic interactions could impair film swelling. Thus, the in-depth understanding of selectivity mechanisms can accelerate the design of ion-selective redox-mediated separation systems for transition metal recovery and recycling.

Finely Tuning Metal Ion Valences of [Fe3-xMx(μ3-OH)(Carboxyl)6(pyridyl)2] Cluster-Based ant-MOFs for Highly Improved CO2 Capture Performances.

Solvothermal reactions of different trinuclear precursors and 5-(pyridin-4-yl)isophthalic acid (H2L) successfully led to four anionic ant topological MOFs as Fe3-xMx(μ3-OH)(CH3COO)2(L)2·(DMA+)·DMF [M = Mn(II), Fe(II), Co(II), x = 0, 1, 2 and 3], namely, NJTU-Bai79 [NJTU-Bai = Nanjing Tech University Bai's group, Mn3(μ3-OH)], NJTU-Bai80 [Fe2Mn(μ3-OH)], NJTU-Bai81 [Fe3(μ3-OH)], and NJTU-Bai82 [Fe2Co(μ3-OH)], which possess the narrow pores (2.5-6.0 Å). NJTU-Bai80-82 is able to be tuned to the neutral derivatives [NJTU-Bai80-82(-ox), ox = oxidized] with M2+ ions oxidized to M3+ ones in the air and the OH- ions coordinated on M3+ ions. Very interestingly, selective CO2/N2 adsorptions of NJTU-Bai80-82(-ox) are significantly enhanced with the CO2 adsorption uptakes more than about 6 times that of NJTU-Bai79. GCMC simulations further revealed that neutral NJTU-Bai80-82(-ox) supplies more open frameworks around the -CH3 groups at separate spaces to the CO2 gas molecules with relatively more pores available to them after the removal of counterions. For the first time, finely tuning metal ion valences of metal clusters of ionic MOFs and making them from electrostatic to neutral were adopted for greatly improving their CO2 capture properties, and it would provide another promising strategy for the exploration of high-performance CO2 capture materials.

Bimetallic bis-Aroyldihydrazone-Isatin Complexes of High O=V(IV) and Low Cu(II) Valent Ions as Effective Biological Reagents for Antimicrobial and Anticancer Assays.

Due to the versatile bioreactivity of aroyldihydrazone complexes as cost-effective alternatives with different transition metals, two novel bimetallic homo-complexes (VOLph and CuLph) were prepared via the coordination of a terephthalic dihydrazone diisatin ligand (H2Lph) with VO2+ and Cu2+ ions, respectively. The structure elucidation was confirmed by alternative spectral methods. Biologically, the H2Lph ligand and its MLph complexes (M2+ = VO2+ or Cu2+) were investigated as antimicrobial and anticancer agents. Their biochemical activities towards ctDNA (calf thymus DNA) were estimated using measurable titration viscometrically and spectrophotometrically, as well as the gel electrophoresis technique. The growth inhibition of both VOLph and CuLph complexes against microbial and cancer cells was measured, and the inhibition action, MIC, and IC50 were compared to the inhibition action of the free H2Lph ligand. Both VOLph and CuLph showed remarkable interactive binding with ctDNA compared to the free ligand H2Lph, based on Kb = 16.31, 16.04 and 12.41 × 107 mol-1 dm3 and ΔGb≠ = 47.11, -46.89, and -44.05 kJ mol-1 for VOLph, CuLph, and H2Lph, respectively, due to the central metal ion (VIVO and CuII ions). VOLph (with a higher oxidation state of the V4+ ion and oxo-ligand) exhibited enhanced interaction with the ctDNA molecule compared to CuLph, demonstrating the role and type of the central metal ion within the performed electronegative and electrophilic characters.

Density Functional Theory Investigation of Cu, Ni, and Ag Inclusion in ZSM-5 to Study Dihydrogen Binding for Cryogenic Molecular Sieve Bed Adsorber in Nuclear Fusion Systems

A computational investigation of Cu-, Ni-, and Ag-introduced ZSM-5 as potential hydrogen storage materials for nuclear fusion energy systems is performed. Among the 24 distinct tetrahedral sites of the monoclinic phase of ZSM-5, systematic periodic density functional theory (DFT) computations have been carried out on 15 experimentally identified T sites that show clear Al site preference and stability in high Si ZSM-5. Adsorption energies estimated from DFT studies have revealed that the T sites in the sinusoidal channels T4 and T10 are the most stable for including all three metal ions. Hence, these should also be considered as potential active sites for dihydrogen binding investigations in addition to the common T12 site in the intersection. The average hydrogen binding energies at these representative T sites were −79 to −45 kJ/mol, which correlates well with both the metal-H2 distance and H-H bond elongation distance. The computed hydrogen bond stretching frequency values were in the 3300 to 3755 cm−1 range upon adsorption of H2 onto the Ni, Cu, and Ag, indicating Kubas-type dihydrogen complex formation. The evidence for dihydrogen binding was also obtained from investigating the σ donation and back donation between the metal ion valence orbitals and the H2σ, H2σ* orbitals through projected density of states and natural bond order analysis. Our analysis indicates that Ni is better stabilized in the framework sites and is considered a potential candidate for dihydrogen binding.

Effect of different ionic valence state doping on the structure and characteristic of BiFeO3‐BaTiO3‐based ceramics

AbstractBiFeO3‐BaTiO3‐based ceramics are promising multiferroic materials for a wide range of applications. In this paper, the effects of different ionic valence state((Ga0.5Ta0.5)4+, Ta5+) doping on the structure and properties of 0.73BiFeO3‐0.27BaTi1‐y(Ga1‐xTax)yO3 ceramics were investigated. X‐ray diffraction analysis showed that all samples were determined by rhombohedral R3c phase and tetragonal P4mm phase. A frequency‐independent dielectric anomaly with obvious thermal hysteresis was detected in all samples, indicating the first‐order ferroelectric phase transition, and the Curie temperatures were all above 600°C. The ferroelectric analysis found that the doping of donor element Ta reduced the coercive field, with a slight decrease of remanent polarization, which can be attributed to the soft effect of Ta element. Meanwhile, the magnetic properties were enhanced for all samples, with a maximum in 15T (x = 1, y = .015) sample, where Mr = .13 emu/g. According to relevant analysis, high‐valence element substitution can enhance the magnetic properties and reduce the coercive field of BiFeO3, while low‐valence element substitution can reduce dielectric loss. This result points out a way for us to choose appropriate doping elements to improve the performance of BiFeO3 ceramics.

Effect of inevitable ions on kerosene droplet formation and evolution

AbstractBACKGROUNDUnderstanding the effect of ions on collector generation characteristics is crucial for adjusting the oil/water interface and enhancing mineral flotation.METHODSWe conducted a study of the kerosene droplet generation process in the presence of NaCl, MgCl2, and AlCl3 using a high‐speed motion acquisition system.RESULTS AND CONCLUSIONSThe results showed that the generation process of kerosene droplets could be divided into two stages, droplet expansion and column contraction, according to variations of the droplet width. With the increasing capillary inner diameter, the generation time of the kerosene droplet increased, while the w/h value (column width/column height) of the kerosene column decreased. When the w/h value decreased to 0, the droplet column ruptured, and the droplet separated from the capillary. As the ion valence increased, the equivalent diameter (d) of the kerosene droplet increased due to the ionic hydration and followed the order dAl3+ > dMg2+ > dNa+. Furthermore, as the ion concentration increased, the equivalent diameter increased with the same capillary inner diameter, and the w/h value decreased. A model of the kerosene column height and capillary inner diameter (R) was established to predict the characteristics of the generated kerosene droplet. © 2023 Society of Chemical Industry (SCI).

Effect of coercive aluminium on the structural and magnetic characteristics of calcium and magnesium based hexaferrites

Aluminum substituted Calcium-Magnesium (Ca-Mg) hexaferrites having general formula Ca0.5Mg0.5Fe12-xAlxO19 (where x is increased with increment of 0.5 from 0.0 to 2.0) are prepared by sol–gel auto combustion technique. X-ray diffraction patterns confirm the hexagonal structure with no evidence of secondary phases. The reduction in lattice parameters is observed as the Al+3 doping level increases. This can be attributed to the short ionic radii of Al+3 ions (0.535 Å) compared to Fe+3 ions (0.645 Å). The obtained c/a ratio falls within the acceptable range of 3.98. Consequently, the formation of magnetoplumbite structure is also confirmed. The SEM image reveals the uniform distribution of particles. The exchange of Fe+3 ions with coercive Al+3 ions led to a decline in saturation magnetization Ms and a significant increase in the coercivity Hc. The magnetic moment mB and Mr of hexaferrites exhibit a decline when Al ions are introduced. This reduction can be ascribed to several factors: the substitution of non-magnetic Al3+ ions in place of Fe3+ ions, the spin-canted ordering of Fe3+ ions, and the valency of Fe ions from 3+ to 2+.

Syntheses, crystal structures and MMCT properties of diruthenium-based cyanido-bridged RuV/VI2-NC-RuII complexes.

The goal of this study was to investigate how the electron-donating capability around the lower valent metal ion and the electron-accepting capability of the higher valent metal ion influence metal to metal charge transfer (MMCT) properties in mixed-valence complexes. A series of trinuclear ruthenium complexes represented as [Ru2(ap-4-Me)3(CH3COO)NCRuCpMex(dppe)][PF6] (CpMex = polymethylcyclopentadienyl, x = 0, 1, and 5; and dppe = 1, 2-bis(diphenylphosphino)ethane, ap-4-Me = 2-anilino-4-methylpyridine) and their one-electron oxidized products were synthesized and fully characterized. The UV-vis-NIR spectra confirmed that as the electron donor character of the CpMex(dppe)RuCN fragment enhanced or the electron-accepting capability of the higher valent diruthenium cluster increased, the RuII → RuV2 or RuVI2 Ru2 MMCT bands shifted to lower energies, which was supported by TDDFT calculations.

Co-doped RuO2 nanoparticles with enhanced catalytic activity and stability for the oxygen evolution reaction.

Efficient and durable electrocatalysts for the oxygen evolution reaction (OER) play an important role in the use of hydrogen energy. Rutile RuO2, despite being considered as an advanced electrocatalyst for the OER, performs poorly in stability due to its easy oxidative dissolution at very positive (oxidizing) potentials. Herein, we report a type of Co-doped RuO2 nanoparticle for boosting OER catalytic activity and stability in alkaline solutions. The replacement of Ru by Co atoms with a lower ionic valence and smaller electronegativity can promote the generation of O vacancies and increase the electron density around Ru, thus enhancing the adsorption of oxygen species and inhibiting the peroxidative dissolution of RuO2 during the OER process. It was found that Ru0.95Co0.05Oy exhibited excellent OER performance with overpotentials as low as 217 mV at 10 mA cm-2 and 290 mV at 100 mA cm-2 in 1 M KOH, as well as outstanding stability in continuous testing for 50 h at a current density of 100 mA cm-2, and nearly no significant degradation after the accelerated durability test of 2000 cycles.

Exploring the relationship between metal ion valency and electron transfer in copigmentation processes of cyanidin-3-O-glucoside in simulated fruit wine solutions

In this experiment, five metal ions (K+, Mg2+, Al3+, Ga3+, and Sn4+) were utilized as copigments to investigate their copigmentation processes with cyanidin-3-O-glucoside (C3OG) in simulated fruit wine solutions. The color characteristics were analyzed using Glories and CIELAB methods, and the copigmentation effects were determined spectrophotometrically. Thermodynamic parameters, including the equilibrium constant (K) and standard Gibbs free energy (ΔG°), were calculated to comprehend the binding affinity between metal ions and C3OG. Ultra-fast femtosecond spectroscopy was employed to monitor the photoinduced electron transfer process between C3OG and cations. Theoretical calculations were also conducted to support experimental findings. The results revealed that the presence of metal ions significantly enhanced the color intensity of C3OG in simulated fruit wine solutions. Higher valency cations, particularly Sn4+, Ga3+, and Al3+, exhibited superior copigmentation effects, resulting in significant bathochromic and hyperchromic changes. Thermodynamic analysis confirmed that the interaction between C3OG and metal ions was spontaneous and exothermic. Ultra-fast femtosecond spectroscopy demonstrated that electron transfer from C3OG to metal ions occurred, with the efficiency of transfer being dependent on valency. Theoretical calculations corroborated the experimental results by highlighting the role of metal ions in stabilizing C3OG/metal complexes through electron transfer. The findings presented in this study contribute to a more comprehensive understanding of pigment/metal complexes and the underlying chemistry behind fruit wine color. Furthermore, it advances the theoretical foundation of copigmentation and broadens its applications in the beverage industry.

Investigation of the process of formation of a chemical current source in the «red-ox» Fe(II) – Fe(III) system in a sulfuric acid environment

Among the technologies designed to save energy, flow-through batteries deserve special attention. Their principle of operation is based on the use of systems of variably valent ions. The aim of the work is to create a chemical current source based on the use of the "red – ox" Fe(II)/Fe(III) system and to determine the patterns of formation of electromotive force (EMF) and short-circuit current (SCC) in acidic solutions depending on the concentration of ions. The experiments are carried out by measuring the EMF formed between graphite electrodes and SCC. A special installation has been assembled, consisting of an electrolyzer with separated electrode spaces, an ammeter, a voltmeter and graphite electrodes. Acidified solutions of iron (II) and iron (III) sulfates served as the electrolyte. In an electrolyzer, the electrode spaces of which are separated by an anionite membrane, when one space is filled with iron (II) sulfate and the other with iron (III) sulfate, an EMF occurs between graphite electrodes. When making contact between graphite electrodes, iron (II) oxidation occurs in the first electrode space, and iron (III) reduction occurs in the second. A chemical current source is being formed. At a concentration of iron (III) equal to 20 g/l, a change in the concentration of iron (II) in the range of 1-40 g / l contributes to a shift in the potential of the graphite electrode to negative values. At a concentration of Fe(III) equal to 1 g/l, the potential value is 509 mV, and at 40 g / l – 475 mV. At a constant concentration of iron (II), the addition of Fe(III) leads to a shift in the EMF value to the right. It was found that as a result of these changes, an increase in EMF and SCC is observed.

Enhanced conduction and phase transition reversibility of O3-type NaNi1/3Fe1/3Mn1/3O2 cathode via Ta doping for high-performance sodium-ion battery

The complex phase transition that occurs during the charge/discharge process leads to poor rate and cycling performance of O3-type NaNi1/3Fe1/3Mn1/3O2 (NFM). In this paper, we propose a novel modification strategy for NFM that involves doping its transition metal layer with Ta5+ ions of higher valence and stronger binding energy to oxygen than the transition metal. The effects of Ta doping on the crystal structure, transition metal valence states, activation barrier energy, and bandgap of NFM were investigated, and the modification mechanisms were explored. The capacity retention of NFM-Ta0.01 (80.15 %) was higher than that of NFM (35.44 %) after 200 cycles. This improvement is attributable to the strong bonding energy effect of TaO, which stabilized the crystal structure of NFM, delayed the transition of the material from the hexagonal O3 phase to the hexagonal P3 phase beyond 3.2 V, and enhanced the phase transition reversibility of NFM. Moreover, Ta introduction increased the sodium layer spacing and reduced the Na+ activation barrier energy of the material from 0.773 to 0.692 eV, and the band gap from 1.7416 to 1.5951 eV, leading to a significant improvement in electronic conductivity. Owing to the synergistic effect of these factors, the discharge capacity of NFM-Ta0.01 at a 5C rate (100.6 mAh g−1) was considerably higher than that of NFM (79.3 mAh g−1). This work presents a proven modification strategy for achieving structurally stable and improved rate performance for NFM.

Effect of Y3+ doping of rare earth element on microstructure and antiferromagnetism of CuFeO2 ceramics

In this work, a set of CuFe1-xYxO2 (x = 0–0.02) specimens were synthesized using the conventional high-temperature solid-state reaction method, and the impact of Y3+ doping on the microstructure and magnetic properties of CuFeO2 ceramics was investigated. The introduction of Y3+ ions in place of Fe3+ ions induced alterations in the microstructure of CuFeO2, leading to lattice distortion. X-ray diffraction analysis confirmed the presence of impurity phases in the CuFe1-xYxO2 series samples at high doping concentrations (x ≥ 0.015). In contrast, low doping concentrations (x ≤ 0.0125) exhibited a singular copper-iron ore structure. The microstructures of the ceramic samples were examined using SEM, findings suggest that the presence of high concentrations of dopants hinders the formation of ceramic samples with high density. XPS analysis reveals that the introduction of a low concentration of Y3+ dopant does not impact the oxidation state of Cu and Fe. Raman spectroscopy results indicate that the doping process weakens the vibration mode of CuFe1-xYxO2 ceramic samples. Additionally, measurements conducted using the PPMS demonstrate that the serial samples undergo two consecutive magnetic phase transitions at temperatures of 16K and 11K. The magnetization versus M − H curve of the doped sample exhibits both antiferromagnetic and ferromagnetic behavior. The increase in magnetic susceptibility can be attributed to the greater magnetic moment of doped Y3+ compared to Fe3+. Consequently, the magnetic transformation of the sample is influenced by various factors, including lattice distortion, alterations in ion valence states, variations in microscopic defect types, and modifications in magnetic interactions.

(Invited) Modulation of Photocatalytic Activity with Oxygen Vacancies in Metal Oxides

Oxygen vacancies commonly exist in metal oxides. The presence of oxygen vacancies alters electronic band structure, changes the chemical valences of metal ions, createS surface disorder and etc. This talk will discuss how oxygen vacancies will modulate light absorption, charge separation, migration, recombination and injection to electrolytes, which in turn affects photocatalytic activities of metal oxides.

Czochralski growth, optical and magneto-optical properties of Ce9.33(SiO4)6O2 crystal

Ce9.33(SiO4)6O2 (CSO) crystals were grown by the Czochralski (Cz) method. Rietveld refinement of XRD patterns confirmed the oxyapatite structure of CSO, XPS analysis revealed the valence of Ce ions in CSO crystals. Magnetization curve and temperature dependencies of the magnetic susceptibility were measured, paramagnetic behavior and magnetic anisotropy have been observed. Photoluminescence and Faraday rotation characteristics of the CSO crystal were investigated at room temperature. Verdet constants of CSO were about 1.6 times as large as those of TGG. Baesd on Van Vleck–Hebb theory, the effective transition wavelength and probability of CSO crystal were calculated and compared with other Ce3+-containing crystals. The absorption and magnetic circular dichroism (MCD) spectra of 4f→5d transitions in Ce3+ ions in CSO crystal were studied.

Re2TiO5: Special dielectric titanates exhibiting abnormally low permittivity and a positive coefficient of resonance frequency

AbstractIn this study, a series of rare‐earth titanates with the general formula Re2TiO5 (Re = Er, Tm, Yb, and Lu) were synthesized and their microwave dielectric properties were reported. The impact of differences in rare‐earth cation radii on the structure and dielectric properties was systematically analyzed. The findings indicated that ceramics of Re2TiO5 (Re = Er, Tm, Yb, and Lu) were crystallized into a cubic structure with space group Fd‐3m, as confirmed by Rietveld refinement and selected‐area electron diffraction patterns. The rare‐earth elements were analyzed for their impact on microwave dielectric properties, considering factors such as ionic polarizability, packing fraction, and bond valence theory. The resulting materials exhibited excellent microwave dielectric properties with a low permittivity (6.95–7.21), high‐quality factors (19 451–20 115 GHz), and low positive temperature coefficient of resonance frequency (19.34–20.90 ppm/°C). The origin of low permittivity was elucidated through the analysis of bond length, X‐ray photoelectron spectroscopy, and impedance spectroscopy. This series of titanates exhibited unusually low permittivity characteristics in the microwave frequency range, which could meet the low signal transmission delay requirements in wireless communication.

Biosynthesis of JC-La2CoO4 magnetic nanoparticles explored in catalytic and SMMs properties

We have reported the synthesis of JC-La2CoO4 magnetic nanoparticles from Jatropha Curcas L. leaf extract in aqueous medium and potential application study in catalytic & Single Molecule Magnets (SMMs). Several techniques were used to investigate the structural, morphological, and elemental composition, particle size, optical properties, catalytic and magnetic properties by XRD, FTIR, SEM, EDAX, XPS, UV–visible and squid magnetic measurement. It was found that the crystallite sizes and grain sizes of JC-La2CoO4 NPs were 11.3 ± 1 and 24.1 ± 1 nm respectively and surface morphology of the nanoparticles looks spherical shape with good surface area. The band gap of JC-La2CoO4 was found to be 4.95 eV indicates good semiconductor in nature. XPS studies shows that La and Co present in + 3 and + 2 oxidation state respectively and suggest the composition formula is La2CoO4 with satisfied all the valency of metal ions. The photocatalytic efficiency of La2CoO4 shows good result against methylene blue (MB) compared to other dyes like MO, NO, RhB in presence of sunlight with rate constant 56.73 × 10–3 min-1 and completely degraded within 115 mints. The importance of JC-La2CoO4 has magnetic properties with antiferromagnetic coupling and SMMs properties with nature.