Search

Electrochemical machining (ECM) is a non-contact type machining technique in which, material is removed from the workpiece by the process of electrochemical dissolution in the presence of an externally applied electric field. Electrochemical turning (ECT) is a variant of ECM which closely resembles the conventional turning operation in configuration. ECT produces parts without burrs, thermal or mechanical residual stresses, and generally possesses a good surface finish. According to the classical theory of electrochemistry, the rate of material removed from the anode surface depends upon several process parameters such as: applied potential, electrical conductivity of electrolyte, gram electrochemical equivalent and mass density of the anode material, and the interelectrode gap. However, in ECT, workpiece rotational speed is also a key parameter which significantly influences the machining rate, but no analytical or empirical relationship in existence takes account of it. In the present research, a numerical model is developed to study the influence of rotational speed in ECT. This model numerically approximates the distribution of current density on the anode surface in two-dimensions without considering the hydrodynamics of the electrolyte flow. For a specific set of other process parameters, simulation results suggest a positive correlation between the machining rate and rotational speed.

Each year, more than four million people around the world undergo bone grafts and prosthesis transplants to treat bone defects and injuries by repairing and/or replacing native bone. As a result, the scaffold holds great promise for the regeneration of damaged or diseased bone tissues. One of the key components is the design of scaffolds that can mimic the structure and function of natural bone. Based on unit cell design, triply periodic minimal surface (TPMS) has attracted the attention of researchers for designing porous scaffolds. In current study, uniform and multi-morphology hybrid graded structures were designed based on TPMS, namely, primitive and I-graph-wrapped package (IWP) minimal surfaces. Furthermore, a computational fluid dynamic (CFD) model was designed based on COMSOL Multiphysics to understand the fluidic characteristics (permeability and wall shear stress) of the structures. The results show that structures reported a permeability of 7.4 – 14.3 × 10 -8 m2, meeting the requirements of natural bone. Moreover, the average wall shear stress of 0.5 – 136 mPa was observed, suitable for osteoblast differentiation and proliferation.

The utilization of lattice structure in engineering components by additive manufacturing (AM) is gaining attention due to its lightweight design, high strength-to-weight ratio, and effective material utilization. Producing holes in additively manufactured lattice structures with dimensional accuracy is challenging. In the current study, we fabricate near circular through-holes on deterministic lattice structured components fabricated by laser powder bed fusion by utilizing electric discharge machining (EDM). In the additively manufactured Inconel 718 (IN718) lattice structure, nodes are connected by strut leaving voids/pores amongst different nodal points. Due to EDM, the nodes at the boundary of the hole experience concentration plasma interaction, heating, and rapid cooling, which causes a substantial change in the microstructure. The selective removal of material from different nodal positions causes uncharacteristic recast layers, partial damages, and uncontrolled cracking of the struts. In the present study, we investigated and characterized the differential behaviour and mechanism of various surface integrity issues associated with the selective material removal of LPBF IN718 lattice structures and their elements (nodes and struts). [ABSTRACT FROM AUTHOR]

There has been a continuous downfall in equipping the Primary Health Centres (PHCs) with infrastructure, facilities, and workforce to provide basic minimum primary healthcare services to the underserved population in the Indian context. The main goal of this research is to look at the infrastructure and manpower in a sample of PHCs in the Kanpur district of Uttar Pradesh, India. The interview template exclusively for Product-Service System (PSS) by Singapore University of Technology and Design-Massachusetts Institute of Technology (SUTD-MIT) was used to study randomly selected samples of 51 PHCs. The data were examined using the Indian Public Health Standards (IPHS) of the Indian government. Some of the key findings included the lack of workforce and their commitment, shortage of space, electricity, and water supply. To find a solution for the found lacunae, this article also discusses about the functioning of Mobile Hospitals (MHs) depending upon the contexts and thus extracting lessons for a new intervention in the primary health care system delivery model. Finally, a new healthcare delivery model in the form of a mobile Primary Health Centre (mPHC) is proposed based on the field study and the synthesis of historical literature on MH. [ABSTRACT FROM AUTHOR]

Wheelchair (WC) design elements are subjected to the accessibility and assistive needs of a person with locomotor disability. In order to pursue a holistic design for a stairclimbing WC, there is a need for literature review on WC functions reported for both stair climbing and plane surface movement. A total of 112 Research articles are reviewed for the purpose of extracting the relationship between WC design elements and the functions associated with them. Stairclimbing technologies are reviewed for their technological assessment in terms of functional elements associated with stairclimbing. Cross-functional mapping between functional elements and their dominant function is performed. Heat map for primary user needs and associated design elements is generated from cross mapping. A design gap for user's functional needs is indicated from the review of literature on prototypes and products of WC. The literature in stairclimbing technology is primarily focussed on stair climbing capability and not on the other functional needs, such as safety, ride comfort, seat comfort, manoeuvrability, etc. For attaining the goal of an effective rehabilitation, it is important to design and develop an assistive technology that can provide maximum accessibility and functioning for a person with disability. In case of locomotor disability, wheelchair (WC) is the most empowering tool that can assist people in both accessibility and activities of daily living. This review of literature was conducted to draw out the functions fulfilled by a WC, such as safety, comfort, propulsion for its users and the associated WC elements like seat, wheels, backrest, etc., that are required to fulfil those functions. WC being the most important technological intervention in the life of a person who cannot walk should be designed with the highest level of empathy. Therefore, each and every aspect of the user's physical and emotional needs should be catered up to the limits of engineering design. The research on stair climbing technologies has also grown exponentially, fuelled by technological growth in engineering mechanisms, ambient awareness sensors, actuators, etc. The review attempts to envelop such technologies and consolidate them on the basis of their capabilities and efficacies. The virtue of stair climbing has been realized through some novel and innovative mechanisms reviewed in this article that can be integrated with the research in field of functional elements required to carry out primary functions of a disabled person, such as safety, comfort, intuitiveness, etc. This review can help in coupling both of them in a more rational way where a designer who is designing the technology is more empathetic towards the design for accessibility. It can also help user in becoming more confident towards adapting a new assistive technology. [ABSTRACT FROM AUTHOR]

In the current work, numerical simulation and experimentation are carried out to investigate the performance of powder mixed dielectric in the electrical discharge micromachining process. Three distinct powders, namely aluminum (electrically conductive), silicon (semi-conductive), and aluminum oxide/alumina (electrically non-conductive) dispersed in the kerosene dielectric, are considered. For a constant applied voltage, a silicon powder particle inserted in the gap immersed with liquid dielectric shows an enlargement in the inter-electrode gap (∼38% and 63% with circular and elliptical powder) compared to the pure dielectric. The enlarged inter-electrode gap increases the machining yield due to improved flushing efficiency. The intensification of the electric field near the particles' surface lowers the breakdown voltage and charging time of the capacitor for the constant inter-electrode gap, resulting in a decrease in discharge energy per pulse and increased spark frequency. The influence of powder material properties and their sizes on breakdown strength is analyzed. Further, the discharge parameters acquired from the electric field numerical simulation of powder mixed dielectric have been utilized to conduct the numerical simulation of single crater formation with pure dielectric and powder mixed dielectric. The simulated single carters' dimensions are validated with the experimentally machined single craters. Numerical simulation and experimentation of powder mixed dielectric depict the effectiveness of aluminum oxide powders in addition to silicon and aluminum powders when dispersed in kerosene host dielectric. [ABSTRACT FROM AUTHOR]

The pandemic, which can be envisioned as a collective nightmare for humanity, was contemplated in July 2020 from the author's residence. Everyone, regardless of social status, had difficult times in their personal and professional lives. Although we researchers are concerned and responsible for enhancing both paradigms of humanity with the help of innovations in emergency situations, this study is based on my experiences pursuing a PhD at the time of Covid-19 in the domain of healthcare infrastructure and service design. The PhD aims to design, develop, and deploy a cost-effective collapsible mobile Primary Health Centre (mPHC) unit specifically tailored for low-resource settings. This report will take readers on an unknown journey through the process of conducting design-led research and disseminating insights for future researchers. [ABSTRACT FROM AUTHOR]

Copper-based ternary metal oxide (i.e., Cu0.52Al0.01Fe0.47O4) impregnated reduced graphene oxide nanohybrid is verified for microbial and arsenic treatment. Growth inhibition of colonies are observed around 99.99% (E. coli), and 99.83% (S. aureus) at 10–20 μg/mL of hybrid dosage, respectively. The inhibition rates for both the colonies are increased to 99.9998% at 80 μg/mL. TEM images have shown insight of cell-content/lipid leakage behavior after inoculating with the hybrid. The efficient hindrance towards microbial colony growth is attributed to better charge transfer, reactive oxygen species generation, and metal-ion release. Maximum arsenic sorption capacities are observed around 248 and 314 mg/g for As(III), and As(V), respectively (Ci ~ 500 ppm). Surface morphology studies onto arsenic adsorption are reported with atomic force microscope, and FT-IR/Raman analysis. A detailed discussion onto individual spectra of As 3d spectra confirmed the occurrence of redox transformation in arsenic species [As(III)]. The variation in the quantity (at. %) of oxygen functional groups in O1s spectra (i.e., M–O, M-OH, and -OH2) onto the hybrid supported the ligand-exchange behavior. Cyclic voltammetry study in arsenic electrolytes (10 µM – 1 mM) provides the occurrence of various in-situ electrochemical reactions supporting the redox activity. A significant electromagnetic wave absorption characteristics of the present hybrid is proposed with plausible airborne antimicrobial-agent abilities. [ABSTRACT FROM AUTHOR]

Single micrometer-sized features were fabricated on ARN-4340 photoresist using a 3D additive technique of two-photon polymerization (TPP). An economic TPP setup capable of producing a large area was developed in the lab using a sub-nanosecond laser. The Photo-initiator (2, 4 Diethyl-9H-thioxanthen-9-one) with a large two-photon absorption cross-section was used to enhance the polymerization. It was theoretically determined that the dimensions of the polymerized features depend on the concentration of the photo-initiator. A novel image-based focusing technique was developed to achieve uniform microsized features on a large area. In the proposed TPP setup, the developed focusing technique was used to determine the area over the sample, which can be polymerized in one go. To demonstrate the capability of the developed setup, microstructures of about 1 µm width were fabricated over an area of 4 cm2. Further, the fabricated sample was used to develop a master mold of Polydimethylsiloxane, which can be used for a soft-lithography replication process. Also, the melt flow technique was explored to reduce the roughness in the fabricated structure. The multi-photon polymerization process using the sub-nanosecond laser is shown to be cost-effective and robust for large area microstructure fabrication. [ABSTRACT FROM AUTHOR]

In this letter, three different wrapping methods i.e., circle having incisions (CI), pentagon and hexagon (P&H) and petals wrapping are proposed for covering of spherical shaped surfaces with flat microwave metamaterial absorber (MMA) without defects. To achieve the better performance, an extensive analytical study was carried for counting the number of unit cells and packing fraction in the aforementioned techniques. It was found that maximum number of unit cell can be wrapped over a spherical ball by using CI method. The maximum packing fraction was found to be in P&H method. Further, we studied variation in the number of unit cells and packing fraction for variation in the shapes (circle, square, and hexagon) and size (2–4 mm) of the unit cell. For experimental purpose, an indium tin oxide coated over polyethylene terephtalate (ITO/PET)-based conformal MMA was designed and then fabricated using excimer laser micromachining. The proposed conformal absorber gives broadband absorption from 6.21 to 15 GHz. Finally, the fabricated absorber was wrapped on a spherical ball and microwave response was measured. The measured microwave response was compared with the simulated response and found to be in good agreement with each other. [ABSTRACT FROM AUTHOR]

This paper aims to examine the influence of nanoclay as secondary reinforcement in carbon epoxy (CFRP) composite on the abrasive water jet machining (AWJM) response for the process parameters, namely, jet pressure (96 and 304 MPa), traverse rate (50, 100, and 150 mm/min), and nanoclay (0.00, 1.25, and 2.50 wt%). The most dominating parameters for AWJM response such as average surface roughness (Ra) characteristics, kerf taper (KT) formation, and material removal rate (MRR) of CFRP plates were investigated by adopting the Taguchi-based statistical method. ANOVA was utilized to obtain the influence of input factors on the process response. Traverse rate was attained as the most considerable factor for all the AWJM response. CFRP embedded with nanoclay showed relatively lower KT formation, Ra, and MRR than the CFRP laminate without nanoclay. Traverse rate with 150 mm/min showed higher Ra, KT formation and MRR compared to 50 and 100 mm/min. Jet pressure with 304 MPa showed lower Ra and KT formation while provided better MRR. The microstructure analysis of the machined surface was illustrated applying FESEM. [ABSTRACT FROM AUTHOR]

The objective of this article is to examine the influence of different weight percentages (wt%) of graphene nanoplatelets (GNPs) on the behavior of mechanical and abrasive wear. Furthermore, the influence of operating parameters, such as, different degrees of applied loads and abrading distance (5‐20 N and 100‐250 m, respectively) at a rotational speed of 200 rpm (1.047 m/s) against SiC paper of 400 grit size was studied. From the present study, it was possible to establish that performance of the glass fabric‐reinforced epoxy composite materials can be improved with incorporation of GNPs. Moreover, incorporation of a large amount (1 wt%) of GNPs was found to noticeably enhance the tribo‐performance, ILSS, and hardness of the composite materials. However, the tensile strength was noted to increase negligibly with incorporation of 1 wt% of GNPs as compared to 0.5 wt% of GNPs. To get an insight into the wear mechanisms, the abraded surface of the tribological samples was examined by scanning electronic microscopy and energy dispersive X‐ray. Their morphology was correlated with wear volume and specific wear rate data trends. Worn surface features analysis indicated that incorporation of GNPs mainly improved the fiber‐matrix interface, which resists easy pullout of fibers from matrix/fillers and enables higher wear resistance. [ABSTRACT FROM AUTHOR]

In this letter, an optically transparent broadband microwave absorber has been developed. The proposed geometry is constructed of the patterned resistive films of an indium-tin-oxide on flexible substrates, such that the structure exhibits broadband absorptivity (above 90%) from 4 to 17.20 GHz (covering C, X, and Ku bands). The novelty of the design lies in leveraging the properties of interdigital capacitance to achieve wide absorption (fractional bandwidth of 124.53%), angular stability, as well as optical transparency compared to the earlier reported broadband absorbers. Moreover, the structure has been extensively investigated through deriving an equivalent circuit model and studying surface current distributions. Experimental validation of the fabricated prototype has also confirmed the potential use of resistive film based broadband absorbers in several applications. [ABSTRACT FROM AUTHOR]

Excimer laser at 248 nm has been used to micromachine holes and channels on stainless steel and polymethyl methacrylate using mask projection methods. The machining is numerically simulated considering the laser beam as a heat source only, thermal diffusion, and melt vaporization. The depth and width of the machined features at different pulse energies and number of pulses are measured by optical profilometry. Both the depth and the aspect ratio (depth-to-width) are found to increase with increasing number of pulses and pulse energies. The depth predicted by the simulations based on the thermal ablation model is closer to the experimental observations for steel as compared with that for the polymer. This allows for the quantification of the contribution of thermal ablation processes in the excimer laser machining of metals and polymers. High-energy pulses are found to have higher ablation efficiency in case of metal and lower ablation efficiency in case of polymer. [ABSTRACT FROM AUTHOR]

In the current study, electro-deposition of hybrid coatings consisting of Cr simultaneously reinforced with nano-scale 3 mol% yttria-stabilized zirconia (YSZ) along with hexagonal boron nitride (Cr-YSZ-BN), graphene (Cr-YSZ-Gr), and diamond (Cr-YSZ-D) was performed using an environmentally-benign trivalent Cr bath. Abrasive wear with ploughing for scratch test is recognized as the dominant wear mechanism in coatings; on increasing the scratch speed, gross spallation occurs in the BN reinforced coatings. While graphene and diamond were strongly adherent to the substrate with no signs of delamination. During fretting, oxidative and three-body abrasive wear in wedge formation mode with severe crack networking was observed in Cr-YSZ-BN. Micro-ploughing was active with intermittent cracking in Cr-YSZ-Gr coatings, indicating lower wear (via solid-lubrication by graphene). Diamond added coating, on the other hand, exhibits fewer cracks with ploughing. High hardness and elastic modulus with a maximum of ~26 GPa and 245 GPa, respectively, were obtained for Cr-YSZ-D coating with a minimum wear rate of ~3.5×10−11 m3/Nm (fretting) and 3.8×10−5 mm3/Nm (scratching). Further, rigid sp3 hybridization of carbon atoms in Cr-YSZ-D leads to the strong interlocking between Cr matrix and diamond, thereby lowering the wear damage of the coating system. The unique combination and uniform dispersion of YSZ and diamond particles displayed enhanced friction and wear resistance (k ~ 1.4×10−3), primarily due to the inherent high hardness of diamond and matrix strengthening by nano and micro-scale particles. Therefore, Cr-YSZ-D coating system emerges out as a highly robust coating capable of providing enhanced damage tolerance towards wear for various tribological applications. • Synergistic YSZ reinforcement with BN, graphene, and diamond in Cr-matrix. • Reduced crystallite size (~15 nm) and high dislocation density (~1011 cm-2) in reinforced coatings. • High compressive residual stresses (~720–1230 MPa) in hybrid coatings. • High fretting damage tolerance (wear rate of ~3.5 × 10–11 m3/Nm) in Cr-YSZ-D hybrid coating. • Low micro-scratch damage (wear rate of 3.8 × 10-5 mm3/Nm) in Cr-YSZ-D hybrid coating. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Mn, and Cu based ternary metal oxide nano adsorbents are studied for arsenic remediation. • XPS of As(3d), Fe(2p), Cu(2p), Mn(2p), and O(1s) is performed to understand remediation mechanism. • As(0) (∼25–78 at.%) onto the adsorbent shows environmentally responsible behavior to address arsenic leaching issue. • Trace metal voltammetry inferred a better As(III) mitigation (∼75–90 % at C i ∼ 1 ppm). • Cyclic voltammetry (CV) confirmed arsenic mitigation, and immobilization by reduction, and sorption. Abstract Arsenic mitigation behavior in aqueous systems is being evaluated for Mn-Al-Fe, Cu-Al-Fe nano adsorbents. Morphological, and vibrational spectroscopy analysis are observed with As-OH, and As-O surface complexes. XPS study of individual As(3d) spectra at different parameters is observed with multiplet peak behavior attributed to redox behavior of Mn-Al-Fe, Cu-Al-Fe. Significant proportions of As(0) signal (∼25 at.% in pH 7, ∼78 at.% in pH 2, ∼58 at.% in pH 12) implicate an environmentally stable behavior of these adsorbents to address the arsenic leaching issue. Adsorption kinetics are observed with Pseudo Second Order (PSO) model, and Freundlich model supported multilayer adsorption behavior is observed for adsorption isotherms. Trace metal voltammetry studies are observed with 75–90 % of As(III) mitigation in aliquot samples. Detailed study of Mn(2p), Cu(2p), Fe(2p), and O(1 s) spectra explains redox active, and surface ligand exchange synergism in arsenic adsorption. Low equilibrium concentrations (C e < 10 ppb) in As(V) systems (C i ∼ 100 and 500 ppb) indicate the drinking water application of these systems. Cyclic-voltammetry (CV) studies implicate the mitigation and immobilization of arsenic species onto adsorbent by both reduction, and sorption phenomenon. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The first derivative of XANES for As(III) adsorbed systems of all adsorbents are observed to have with mixed oxidation. • As(V) adsorbed samples of Ni, and Cu systems agree with that of As(V) standards. • Both reduction and oxidation behavior of arsenic is observed on to these metal oxide adsorbents. • EXAFS analysis was observed with As O bond distances in the range of 1.7–1.8 Å. • The As-M bond distances are around 2.7, 3.2 and 3.6 Å confirmed the formation of surface complexes. Abstract The present study is about surface complexation behavior of arsenic species adsorbed onto ternary metal oxide adsorbents (Ni-Al-Fe, Co-Al-Fe, Mn-Al-Fe, and Cu-Al-Fe). The analysis is carried out by X-ray absorption spectroscopy (XAS) tool. XANES (μ(E) vs. E) spectra close to the absorption edge (i.e., As K -edge) of all samples are observed along with the As(III) and As(V) standards. The first derivative of XANES for Ni-As(V), and Cu-As(V) samples agree with that of As(V) standards, respectively. Whereas, As(III) adsorbed adsorbent systems (i.e., Ni, Co, Mn, and Cu) are observed with mixed oxidation state of arsenic. A total of 65–85 % is observed with initial oxidation state (As(III) or As(V)), and remaining 15–35 % is observed with modified oxidation state (As(V) or As(III)) that explains the occurrence of possible charge transfer. EXAFS analysis shows the As-O bond distances in the range of 1.7–1.8 Å. The corresponding As-M bond distances are around 2.7, 3.2, and 3.6 Å which confirms the formation various edge sharing (2E), and corner sharing (2C, 1V) surface complexes. Surface coverage is understood as an important parameter as bidentate attachments (2E, 2C) are evident in As(III), and As(V), but monodentate attachments (1V) are only observed in As(V). [ABSTRACT FROM AUTHOR]

The understanding of mechanistic insights in environmental remediation and mitigation systems is attracting larger attention, in recent days. Here in, aluminium substituted copper ferrite impregnated rGO hybrid (CAF-rGO) is verified to understand the adsorption/electrosorption mechanism of arsenic in aqueous systems. Near-surface study (XPS: As 3d, Cu 2p, Fe 2p, Al 2p, O 1s, C 1s) proposes redox, and ligand exchange reactions between contaminant, and CAF-rGO. Adsorption capacities are observed around 128.8 mg g−1 [As(III)], 153.5 mg g−1 [As(V)] with Freundlich model isotherms. Kinetics study follows the PSO model with influence of solar light (> 420 nm). Cyclic voltammetry (CV) analysis in different molarity conditions observed with signals around +0.1 and −0.6 V confirm the redox abilities, and N 2 /O 2 purged environments understood that electrosorption occurred through both reduction and sorption. Electrosorption study with pH variation shows the effect of protonation on the redox activity of individual arsenic species. Consistent signal around −0.6 ± 0.05 V in all the CV plots (i.e., Molarity, Environment, pH) recommends the usage of CAF-rGO for arsenic mitigation. Possible influence of photo-current (∼40 μA/cm2 at ∼ 0 V) towards As(III/V) decontamination is understood though photoelectrochemical analysis. Impedance plot shows low-resistance and better diffusion of arsenic oxy-anions during light irradiation. Synergistic nature of CAF-rGO generates reactive oxygen species (i.e., ●OH/●O 2 −/ 1 O2) in mitigating highly toxic As(III) species is also detailed in the present work. Image 1 • Mechanistic insights of arsenic (As) adsorption and electrosorption in aqueous systems. • In-situ CV analysis in various molarities, gas purging environment and pH conditions. • A constructive correlation is drawn between individual redox signals and CV plot areas. • Photo-catalytic aspects on As loading and photo-electrochemical behavior (I vs. t, EIS). • ROS signals onto the hybrid surface in influencing As remediation and mitigation. [ABSTRACT FROM AUTHOR]

Aluminum (Al3+) doped manganese (Mn)/copper (Cu) ferrite impregnated rGO hybrids are verified for photo-electrocatalytic water-splitting and super-capacitor electrode applications. Energy band gaps of 2.17 eV (Mn) and 2.25 eV (Cu) confirm photocatalytic activity in the visible-band. High anodic photo-currents around 18–40 and 2–9 mA/cm2 (1 V vs. Ag/AgCl) are observed for Mn and Cu systems. Formation of oxygen vacancies due to aluminum doping assisted in efficient charge transfer behavior both at surface and lattice orders due to the structural adjustments. 2-D rGO surface disorders (I D /I 2D) emphasized the retardation of the charge recombination at the metal-oxide and rGO junction. During visible-light irradiation current densities are increased by 0.7–9.2 mA/cm2 with a better redox behavior. The difference in transient currents are observed around 0.01–0.02 mA/cm2 at 0 V vs. Ag/AgCl [0.7 mA/cm2 at 0.5 V]. Intrinsic photo-current at zero voltage infers built-in potentials at the hybrid and electrolyte interface (Schottky- junction). Impedance study implicates better electron-transfer/ion diffusion characteristics during photon irradiation with a semi-infinite diffusion rate-limiting step. Specific-capacities (Three-electrode) are observed around 216 F g−1 (Mn), 142 F g−1 (Cu) with combined pseudo-capacitance and EDLC characteristics. Li+-intercalation results in ultrahigh stability up to 100,000 cycles (t ~ 69.4 h) at 0.8 V s−1 with a capacity retention of 127%. Two-Electrode performance shows 99.1% capacity retention after 5000 cycles with decrease in the impedance (1.38 Ω to 1.06 Ω), and a maximum areal energy density of 0.54 μWh cm−2 at power density of 50 μW cm−2. Image 1 [ABSTRACT FROM AUTHOR]

Arsenic [As(III) and As(V)] adsorption on aluminum substituted cobalt ferrite (Co-Al-Fe) ternary metal oxide adsorbent is reported by means of qualitative and quantitative spectroscopy tools. IR and Raman active signals were observed around 810-920 cm -1 band indicate different As-OH complexed and As-O uncomplexed stretching vibrations on to the adsorbent. The adsorption behavior of arsenic (III and V) onto these adsorbents is studied as a function of contact time, different concentrations, and pH conditions. The kinetics study on adsorption were performed to understand nature of adsorption which supports the Pseudo Second Order (PSO) model. The adsorption isotherms study indicates Freundlich type of adsorption. The maximum adsorption capacity of Co-Al-Fe adsorbent is observed around 130 and 76 mg g -1 for As(III) and As(V) systems, respectively. Detailed XPS study of As 3d, Fe 2p, Co 2p, and O 1s spectra has been reported in explaining the redox behavior and ligand exchange reactions in supporting arsenic adsorption mechanism.