ABSTRACT This study aims to valorise mining waste from the Tunisian Guarn El Halfeya abandoned Pb‐Zn mine and to assess its potential as a low‐cost secondary raw material for the production of alkali‐activated geopolymer materials (AAGMs), offering a dual environmental benefit: waste reuse and immobilisation of potentially toxic elements (PTEs). Unlike conventional studies relying exclusively on synthetic or industrial precursors, this work partially or fully substitutes metakaolin, the benchmark precursor, with unprocessed mine tailings, highlighting the direct applicability of raw geological by‐products. Formulations were activated with NaOH at 8, 10 and 12 M and then cured at 60°C for 7–28 days. To characterise the raw materials and to optimise the AAGMs, several techniques were employed, including XRD, XRF, granulometry, TG/DTA, FTIR an dielectric spectroscopy, mechanical strength, SEM and leaching tests. Results of mine waste characterisation revealed a high content of calcite‐rich matrix associated with quartz and a median particle size of 14.5 μm. AAGMs produced with ≤ 50 wt% waste and activated with 10 M NaOH exhibited strong physicochemical performance, effectively stabilising PTEs while achieving high compressive strength, making them promising candidates for contaminated site remediation and sustainable construction materials. Leaching tests clearly indicate that the composition of the AAGMs strongly affects the chemical stability and mobility of PTEs. Notably, dielectric spectroscopy, rarely applied in this field, reveals a microstructural transition: as waste content increases, isolated conductive particles progressively form interconnected ionic transport networks, providing new insights into the structure‐property relationships of mine‐waste‐based geopolymers.

This research’s prime focus was to synthesize the nano-sized Nd[Formula: see text]-substituted Sr[Formula: see text]Nd x Fe 8 O[Formula: see text] T-type hexaferrites with the composition ([Formula: see text], 0.05, 0.1 and 0.15) to augment indulgence of their magnetic properties. Such insights are essential for exploring the imminent applications of these materials in the biomedical field. The X-ray diffraction patterns revealed that the samples were single-phase hexagonal ferrites. The crystallite size varied from 25.10[Formula: see text]nm to 25.39[Formula: see text]nm. The P–E loops indicated that the materials’ lossy behavior decreased with Nd[Formula: see text] content, unveiling an improvement in ferroelectric behavior. The saturation magnetization (M s ) values varied from 4.79[Formula: see text]emu/g to 18.41[Formula: see text]emu/g and coercivity from 1955.90[Formula: see text]Oe to 2614.34[Formula: see text]Oe. The coercivity value suggests that the material might be used in data storage, recording media devices and storage and permanent magnet applications. The heat generated during the alternative magnetic field hyperthermia process establishes these materials as a formidable intervention for decisively targeting tumors, leveraging elevated temperatures to disrupt their growth and survival, paving the way for a significant breakthrough in cancer therapy.

We report a comprehensive study of the temperature-dependent structural, magnetic, vibrational, and dielectric properties of Al-substituted M-type hexaferrites SrFe12-xAlxO19. Neutron powder diffraction and M & ouml;ssbauer spectrometry show that Al3+ preferentially replaces Fe3+ at spin-up octahedral sites (2a, 12k), disrupting the exchange coupling with the spin-down 4f tetrahedral sites and leading to a progressive reduction of site-specific magnetic moments and a systematic decrease in the Curie temperature, supported by temperature-dependent susceptibility measurements. Raman spectroscopy reveals pronounced phonon anomalies near T-C, particularly in modes associated with bipyramidal Fe-O vibrations, reflecting the weakening of both 4e-12k and 4e-4f exchange pathways. However, the coercive field exhibits a dramatic increase, reaching & micro;H-0(C) similar to 1.2 T for SrFe9.6Al2.4O19, among the largest values reported for this class. Susceptibility measurements suggest that Al substitution, while weakening the superexchange network, contributes to the stabilization of single-domain behavior.

Air pollution is a problem of great concern, with increasing atmospheric concentrations of toxic Volatile Organic Compounds (VOCs) such as BTEX (benzene, toluene, ethylbenzene and o-xylene). We report the development of adsorbant materials derived from tuna fish bones. Tuna Bone Char (TBC) was obtained with a pyrolysis process; and activated with K2CO3 treatment (indicated as KTBC, due to the potassium carbonate activation). Characterisation showed that the activation protocol led to a significant increase in the surface area - from 97.45 to 1826.59 m(2)/g for TBC and KTBC; furthermore, the activated material also showed higher porosity (total pore volume of 2.22 cm(3)/g, micropore volume of 0.38 cm(3)/g). BTEX dynamic adsorption tests showed KTBC excellent adsorption properties, particularly with o-xylene (adsorption capacity q of 147 mg/g). The higher adsorption of o-xylene was explained considering its kinetic diameter matching KTBC pore size dimension. KTBC also showed to be very efficient in humid conditions (q = 61.2 mg/g). Repeated tests with the same powder indicated a 20 % decrease after the first cycle, with no further decrease in additional cycles. Empirical regression models for q(0) and k(Th) (Thomas model), and tau and K-YN (Yoon-Nelson model) were developed for BTEX breakthrough curves and showed agreement with experimental breakcurve data (R-2 > 0.905). These results show that bone char can be used for gaseous pollutants with the activation playing a key role in surface modification and performance enhancement. This research offers a sustainable and effective route to convert marine biowaste into advanced adsorbents for VOC and air pollution control.

A novel V-type hexaferrite with the substitution of strontium by divalent nickel, having the chemical formula Sr1-xNixFe8SnO15 (x = 0.0, 0.2, 0.4, and 0.6), is synthesized by employing a sol-gel auto combustion method. X-ray diffraction (XRD) patterns confirmed the hexagonal phase for all the samples; however, an extra peak due to SnO2 was observed. With the increase in the Ni2+ concentration, the values of lattice constants a (& Aring;) and c (& Aring;) and unit cell volume decreased slightly, and the crystallite size was calculated to vary in the range of 19 to 21 nm for all the samples. Transmission electron microscopy (TEM) analysis indicated that the average particle size lies in the range of 70-110 nm for all the samples. The samples have the maximum dielectric constant (epsilon ') and minimum electrical modulus (M ') at low frequency (<100 Hz); when the frequency is gradually increased, both the parameters stabilized and became constant, with real permittivity values from 61.4 to 37.4 between 1 kHz and 10 MHz, which are high values for hexaferrites. AC conductivity increased exponentially with the increase in frequency, while Ni content had little effect on these values. The polarization versus electric field (P-E) loops showed electrical polarizability but represented a lossy behavior that lessened with increasing Ni2+ content. The optical band gap energy values increased slightly with Ni2+ substitution over the unsubstituted sample. The saturation magnetization (M-s) increased with Ni substitution from 31.1 emu g(-1) in the pure V ferrite to a maximum value of 43.6 emu g(-1) for x = 0.4, and remanence magnetization (M-r) values were also significant. However, a drastic decrease in coercivity (H-c) was observed with Ni substitution, from a reasonably hard ferrite (H-c = 2218 Oe, 176.5 kA m(-1)) for x = 0.2 to very soft ferrites with x = 0.4 and 0.6 (H-c of around only 200 Oe, 16 kA m(-1), a ten-fold decrease). The small grain size, reasonable M-s, and great variation in H-c with x between hard and soft ferrites while maintaining some M-r signify that these V-type hexaferrites could also be interesting materials for potential spintronic, magnetic memory, and microwave absorption applications.

In this work, and for the first time, the production of waste-based magnetic geopolymer spheres by a simple heat treatment under a reductive atmosphere is reported. Upon heat treatment, the iron oxide present in bauxite wastes (red mud), used as a solid precursor, is reduced to magnetite, thus producing magnetic spheres without the need for the addition of any secondary magnetic materials. The magnetisation of these mm-size materials reached 5.34 A m2 kg-1, suggesting they contain up to 6 wt% magnetite. This was demonstrated to be sufficient for their magnetic separation/removal, without the need for the addition of any extra magnetic iron oxides to the waste material. The magnetic spheres were then evaluated as sorbent materials for the removal of lead from water, selected as a model pollutant compound. These porous bulk-type sorbents showed high metal removal efficiency reaching an uptake value of 19 mg/g at pH 5 after 24 h of contact time. These promising results, and the easy post-treatment recovery of the waste-based magnetic spheres by the use of inexpensive permanent magnets, demonstrate the potential of the proposed strategy to address environmental concerns.

Peloids are natural therapeutic muds or clays used in balneotherapy and other health treatments. The aim of this study is to prepare and qualify three artificial peloids by maturation for 360 days of some Tunisian smectitic clays with a naturally chlorinated sodic mineral water from a spring in Korbous, Tunisia. This was done to improve our understanding of the behaviour of these clays and the physicochemical changes that affect the clays during maturation, with the purpose of providing suitable raw materials as a solid phase for peloid preparation. The results showed that parameters such as mineralogy, geochemistry, granulometry, cation-exchange capacity, consistency parameters (Atterberg limits and plasticity index), specific surface area, cooling kinetics and pH are all affected by the geochemistry of the thermal water used during maturation. Mineralogical modifications mostly concern the clay minerals' contents, particularly smectite, and subordinately the dissolution of gypsum and the neoformation of halite. The observed improvements to the plasticity index and cooling kinetics can be explained by the ability of water molecules, and especially cations, to diffuse into the clay particles. The main exchangeable cations are Na+ and Ca2+, along with Mg2+ and K+, which promote swelling and increase water retention and consequently retention of heat in thermal spa treatments. The chemical composition of the major elements is closely linked to the mineralogical compositions of the clays, and also to the chemical composition of the thermal water used in their maturation. The safety profiles of the peloids obtained at different maturation times were evaluated, particularly regarding their content of potentially toxic elements such as arsenic.

Hydroxyapatite (HAp, Ca10(PO4)6(OH)2) is the major inorganic component of bones, with high bioactivity and biocompatibility, and pores in the 50-200 μm range can facilitate cell anchorage and proliferation. HAp was synthesised through a rapid sol-gel method, avoiding the usual long aging process typically required for sol-gel HAp. Acetate and nitrate precursor salts were compared, to produce bioceramics having different porosities induced via the addition of hydrogen peroxide (H2O2) pore-forming agent. 3-10 wt% H2O2 was added, and the resulting bioceramics calcined at 400 and 700 °C. Microstructure, composition, specific surface area and macro/mesoporosity were analysed, and bioactivity and cytotoxicity/biocompatibility evaluated by immersion in simulated body fluid (SBF) and MTT assays on MG63 osteoblast cell lines. When heated to 400 °C HAp was the only calcium phosphate phase present, but after heating to 700 °C they were a mixture of HAp and β-tricalcium phosphate (β-TCP, Ca3(PO4)2). The bioceramics exhibit high bioactivity, crystallising HAp from SBF, and most were biocompatible, with cell viabilities of 110-139% for samples with 3 wt% H2O2 derived from nitrates, or from acetates heated to 700 °C. This is the first time that HAp-based bioceramics derived from a rapid sol-gel process have been produced with such induced porosity.

Phosphate nanomaterials, such as hydroxyapatite/β-tricalcium nanoparticles (nHAs) derived from food industry by-products, offer a sustainable alternative to enhance P-use efficiency in agriculture. However, their limited solubility remains a challenge. This study first investigated the mechanisms of P solubilization of salmon and tuna bones (SnHAs and TnHAs) in fifteen strains of phosphate-solubilizing bacteria (PSB) by an in vitro system. Then, best-performing strains were assembled in a consortium and tested in vivo on maize. We hypothesized that combining nHAs and the PSB consortium inoculated as seed coating (SC) outperforms single treatments alone in promoting plant growth and P cycling, and ensures the establishment in plant-soil system without a bacterial reinforcement (BR) by an additional inoculum suspension. The synergistic effect of nHAs and PSB was proved, improving maize root (+22 %) and total plant biomass (+29 %), as well as P (+32 %) and K (66 %) uptake compared to single treatments. With nHAs and SC, P-use efficiency and recovery increased by 25 % and three-fold, respectively, compared to nHAs alone or with bacterial reinforcement. Consistently, root and substrate bacterial biomass were associated with nHAs plus SC, while nHAs alone or with PSB upregulated PHT1;1 and PHT1;2 transporter genes in maize. Finally, linking the in vitro and in vivo system, we demonstrated that propionic acid production and P-solubilization efficiency of PSB co-applied with nHAs are key drivers of maize growth and P uptake. Our findings indicated that co-applying nHAs and PSB through SC offers a sustainable strategy to improve maize P-use efficiency.

Materials based on graphitic carbon are used for environmental remediation, due to their high surface area and their capacity to adsorb pollutants in liquid environments. Carbonaceous materials derived from residues are particularly interesting, as their synthesis has a smaller impact on the environment. In the present work, we report a preliminary study on the preparation of graphitic carbon made from cork waste powder modified with magnetic nanoparticles (MNPs). This is the first time such composites were prepared using pyrolysed/carbonised cork, from a powder residue of cork stopper production. This makes the process sustainable and in line with the circular economy. The composites were prepared by vacuum infiltration of the MNPs on pyrolysed cork powder, with a successive thermal treatment, resulting in a carbon material that retained the porous microstructure of the original cork, ideal for the absorption of pollutants or separation of oils and water, while also being magnetically separable afterwards. It was seen that post-infiltration heating was better in air than under nitrogen, with the nitrogen atmosphere and presence of highly porous carbon possibly partially reducing magnetite to FeO, with a reduction in magnetic properties. MNPs with different chemical compositions were tested - zinc ferrite (ZnFe2O4) and magnetite (Fe3O4) - with the magnetite composites showing the highest magnetisation. Moreover, magnetite particles of different dimensions were considered: 6, 9 and 15 nm; results indicated that the 9 nm magnetite NPs were the most easily infiltrated; the magnetisation, however, was higher for the composites with the 15 nm magnetite NPs (about 9 emu g-1), despite the oxide component comprising only around 12 wt% of the composite, due to their greater initial magnetisation. This value is higher than those of similar composites prepared using carbon from other natural sources. SEM analysis showed the presence of MNPs on the surface of the material, with the particles being on the nanometric scale and showing no aggregation on the micron scale. Composites prepared with these 15 nm MNPs also showed greater stability in both water and an organic solvent (chloroform) and were demonstrated to be magnetically separable from suspensions, making them the most suitable for environmental remediation applications.

The quantitative study of antibiotics is important in various biomedical applications. Cefixime is a third-generation cephalosporin medication used to treat a range of bacterial infections. In this study, the green synthesis of sodium β-type hexagonal ferrite nanomaterial (NaFe11O17-NMs) was carried out from ginger root extract via the sol-gel method. The as-synthesized NMs were characterized via atomic force microscopy (AFM), field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometer (VSM) analysis, and UV-visible spectroscopy. Furthermore, the drop-casting process is used to synthesize an efficient electrochemical sensor by coating a gold electrode (AuE) with NaFe11O17 NMs (NaFe11O17-NMs/AuE), which helps in the sensitive and selective quantification of cefixime. The as-prepared electrochemical process had a remarkably low detection limit of 14 nM. The as-fabricated sensor was effectively used to quantify cefixime levels in clinical samples and pharmaceutical formulations, with recoveries ranging from 95.20% to 102.48%.

A novel V-type hexaferrite with the substitution of nickel, having the chemical formula Sr 1− x Ni x Fe 8 SnO 15 ( x = 0.0, 0.2, 0.4, and 0.6), is synthesized by adopting the sol–gel auto combustion method.

Polycrystalline samples of Al 3+ -substituted barium–cobalt U-type hexagonal ferrites, with the chemical composition Ba 4 Co 2 Fe 36− x Al x O 60 ( x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0), were synthesised.

Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 emerged as one of the most technologically important lead-free piezoelectric compositions, and has undoubtedly shown remarkable advancements with regards to applied research. This article outlines the technological relevance of the Ba(Zr,Ti)O3-(Ba,Ca)TiO3 based piezoelectric system, and summarizes the developments made in various traditional and emerging potential application areas. The outstanding piezoelectric properties with d33 ∼600 pC/N in BZT-50BCT laid the foundations for its applicability in mechanical energy harvesters. In recent years, its utility in energy storage and electrocaloric cooling applications have propelled its prominence in addressing the challenges associated with sustainable energy solutions. Strikingly, the characteristic ability to autonomously generate electric surface potentials with low cytotoxicity also renders the BCZT system a promising candidate for biomedical applications. Other applications explored include magnetoelectrics, photoluminescence and photocatalysis.Lastly, the future perspectives of the BCZT system are outlined based on the current research status and the existing scientific challenges.

This study aims to reduce the impact of the cationic dye methylene blue (MB) by removing it from aqueous solutions using geopolymer silicate bricks made from local Tunisian silica sands combined with metakaolin. The chemical–mineralogical characterization (XRD, XRF) of the raw silica sand,collected from the Jebel Zemlet el Beidha region of the south of Tunisia, shows it to be mainly formed of quartz and potassim-based feldspars, with smaller levels of calcite and kaolinite.Between 10–30 wt

In this study, the effect of salinity in wastewater on the adsorption capacity of a bone char material prepared through pyrolysis of tuna bones at 1000 degrees C was investigated for two pharmaceuticals, tramadol (TRA) and venlafaxine (VNF), both contaminants of emerging concern. This is the first time that the adsorption efficiency of a bone char-type material was tested in such conditions. The Tuna Bone Char (TBC) was composed of calcium phosphate (hydroxyapatite), and graphitic carbon. The TBC is a nanostructured material (particle size 30-60 nm), with a surface area of 100.67 m2/g 2 /g (higher than other waste-derived type materials), and a total pore volume of 575.2 mm3/g. 3 /g. TBC capacity to adsorb TRA and VNF, individually or combined, was evaluated in batch experiments using different aqueous matrices: water, non-saline wastewater, and wastewaters with different salinity levels (7.5 and 12 g/L). For individual pharmaceuticals, the TBC had a higher affinity for TRA than VNF. The presence of salts in wastewaters led to a decrease in the TBC adsorption capacity but it was still effective for pharmaceuticals adsorption. Indeed, for the individual pharmaceuticals, the TBC adsorption capacity (qt) t ) was 0.72-2.14 and 0.77-1.70 mg/g for TRA and VNF respectively, depending on the aqueous matrix. With both pharmaceuticals present, lower qt t values were experimentally obtained for TRA and VNF. The potential of the TBC, a material derived from a by-product of the fish industry, to be used for environmental remediation in different environments, such as saline wastewaters was demonstrated, widening the range of its potential applications.

Cork is a renewable and sustainable material, highly porous and lightweight. We valorised waste cork and recycled wine stoppers to make pyrolysed/carbonised solid cork, for use as economic and sustainable microwave (MW) absorbers at the microwave X-band (8-12 GHz), without binder or additives. Although cork is already a very lightweight material (0.16 g cm-3), the pyrolysed cork is five-times less dense at 0.031 g cm-3, was amorphous graphitic carbon, and had an excellent shielding effectiveness (SET) of -18 to -38 dB, depending on thickness, with attenuation of the electromagnetic energy through internal reflection within the cellular cork structure. Furthermore, this ultra-light-weight material has an extremely high MW specific shielding effectiveness or efficiency (SSE), between -640 to -1235 dB g-1 cm3 over the entire X-band range, depending on thickness (3.0-8.6 mm), one of the highest reported for any pure carbon material, this upper value being more than twice that of any previously reported graphite-based foams.

&lt;p&gt;Hydroxyapatite nanoparticles (nHAs) deriving from by-products have gained increasing interest as novel phosphorus (P)-based fertilisers, since they can provide a slow P release, minimising P losses and adverse environmental side-effects, and reducing the dependency of agriculture on mineral fertiliser inputs. Phosphate solubilising bacteria (PSB) have proven to release P available for crop uptake from different inorganic sources (e.g.&lt;em&gt; &lt;/em&gt;tricalcium phosphate, TCP, hydroxyapatite, HA). In the present study, nHAs were prepared from salmon (S-nHAs) and tuna (T-nHAs) bones by a calcination process, followed by a high energy ball milling. The obtained fine powders were characterised by scanning electron microscopy (SEM) for size and shape and by X-ray diffraction (XRD) for crystal phase composition. The phosphate solubilisation activity of seven selected PSB strains belonging to &lt;em&gt;Pseudomonas &lt;/em&gt;and &lt;em&gt;Paraburkholderia &lt;/em&gt;genera was &lt;em&gt;in vitro&lt;/em&gt; investigated under acidic (pH = 5.5) and alkaline (pH = 7.5) conditions by a quantitative assessment of the solubilised PO&lt;sub&gt;4&lt;/sub&gt;&lt;sup&gt;3-&lt;/sup&gt; from TCP, S-nHAs and T-nHAs over time. Moreover, time trend of pH and organic acids in the liquid media were investigated. Characterization of S-nHAs by XRD and SEM revealed a biphasic composition of the material consisting of TCP and HA &amp;#8211; about 50 wt% of each phase - and a heterogeneous rounded-shape (&amp;#216; &lt; 50 nm) material. By contrast, XRD pattern of T-nHAs showed a single-phase composition mainly made of pure HA (&gt; 95 wt%) and SEM micrographs exhibiting an elongated shape uniform in size (200 x 30 nm). At day seven, &lt;em&gt;Pseudomonas graminis&lt;/em&gt; PG0319 solubilised the highest proportion of the total PO&lt;sub&gt;4&lt;/sub&gt;&lt;sup&gt;3-&lt;/sup&gt; in the TCP substrate under acidic pH (83%), followed by &lt;em&gt;Pseudomonas rhodesiae&lt;/em&gt; PR0393 and &lt;em&gt;P. graminis&lt;/em&gt; PG1211 (79% and 72%, respectively). In S-nHAs under alkaline pH, &lt;em&gt;Paraburkholderia terricola&lt;/em&gt; PT0405, PR0393, PG0319 and PG1211 solubilised from 53% to 57% of the total PO&lt;sub&gt;4&lt;/sub&gt;&lt;sup&gt;3-&lt;/sup&gt;, whereas in T-nHAs under acidic pH the maximum solubilisation efficiency was 27% by PT0405 at day seven. The difference in the solubilisation of S-nHAs and T-nHAs is due to the lower solubility of HA in comparison with TCP. Values of pH in in the liquid media decreased over the time along with an increasing PO&lt;sub&gt;4&lt;/sub&gt;&lt;sup&gt;3-&lt;/sup&gt; solubilisation activity, suggesting an extracellular secretion of organic acids by PSB. Accordingly, differential patterns of organic acids were detected among strains with TCP as well as S-nHAs and T-nHAs. Notably, gluconic, propionic, fumaric and acetic acids played key roles during P solubilisation with all the tested strains, substrates, and pH conditions. Our results indicate that the use of microbial inocula together with P-based nanofertilisers is a promising option for a sustainable agricultural transition.&lt;/p&gt;

A growing number of synthetic plastics derived from fossil fuels are produced, and improper plastic waste management has caused a lot of pollution problems. There are many microplastics in the environment, and they disintegrate slowly in soil and water. The properties of microplastics include long residence times, high stability, high fragmentation potential, and the ability to adsorb other contaminants. Invertebrates and planktonic organisms are easily able to accumulate microplastics in aquatic species. Therefore, microplastics (MPs) must be removed from the water and other media. This paper aims to review the occurrence, raw polymers and additives, and remediation methods for removing microplastics from the environment. Several methods are available for removing contaminants, including sorption, filtration, and chemical treatments. Various removal methods are discussed along with their methods, efficiency, and advantages.

Indium substituted X-type Ba2Zn2InxFe28-xO46 (0.0≤x≤2.0) ferrites were synthesised by a citrate-gel aqueous combustion technique, and heated at 1300 °C. XRD, FTIR, SEM with EDX, magnetic hysteresis, Mössbauer spectroscopy, UV–visible spectroscopy, and dielectric measurements up to 20 GHz have been carried out to study the modification of the structural, morphological, magnetic, optical and frequency dependant dielectric properties when indium is introduced, replacing iron in the lattice of X-type hexaferrites. XRD analysis reveals formation of a major X-type phase in all compositions. The systematic rise in lattice constants (a, c) along with cell volume (V) confirm the replacement of iron by indium. Magnetic hysteresis loops reveal a soft ferrite nature with low Mr/MS values, suggesting a multidomain structure in all samples. The HC values decrease from 22.22 kA m-1 to 12.18 kA m−1 (279 Oe to 153 Oe) with increasing indium, while magnetisation remained high between 56 A m2 /kg and 62 A m2/kg for all samples. Room temperature Mӧssbauer spectra of all samples were fitted with six Zeeman sextets of five different magnetic sublattices. It was ascertained that In-substitution reduces the Fe population in the k (spin up) sublattice, resulting in a reduction in magnetisation. The average hyperfine magnetic field is also reported to decrease with Indium substitution for all samples. The value of the isomer shift (δ) confirmed that the iron-ions are in high spin Fe3+ state. The complex impedance and electric modulus plots reveal non-Debye type relaxation in all samples at 100 Hz to 2 MHz.