Formation Of Impurity Phases Research Articles

Effect of carbide formation on phase equilibria and compositional modulation of transformation properties in (Mn,Fe)2(P,Si) alloys

Practical implementation of efficient magnetocaloric effect-based refrigeration and energy conversion applications requires the design of whole alloy families with narrow tolerances on the transformation properties, and therefore composition, of the component alloys. In the promising class of magnetocaloric (Mn,Fe)2(P,Si) alloys, this task of compositional tuning is made especially difficult by the observed co-existence of several P-depleted impurity phases, which for example, increases both the P content and transformation hysteresis losses of the main quaternary phase. In this work, we study the mechanisms that induce impurity phase formation in the Mn–Fe–P–Si system, and investigate the impact of sequential carbide formation on observed phase microstructure along with its effect on the composition and transformation properties of the (Mn,Fe)2(P,Si) phase. Using quantitative analyses to measure the composition within main and impurity phases in samples throughout the bulk alloy space, we establish that (1) repeated processing steps increase the content of a (Mn,Fe)9Si2 carbide phase, resulting in (2) deviations in the magnetocaloric (Mn,Fe)2(P,Si) phase from bulk nominal composition of up to ∼4 at. %. Finally, we map out (3) the dependence of transformation critical temperature, hysteresis, and enthalpy on the composition of the (Mn,Fe)2(P,Si) phase of interest. Together, these results suggest carbon impurities can have a critical impact on magnetocaloric transformation properties in (Mn,Fe)2(P,Si) alloys, since 0.3 wt % carbon content can cause critical temperatures and hystereses to deviate by more than 95 K and 8 K from desired design values.

Influence of Ti doping on microstructure and electrochemical performance of LiNi0.5Mn1.5O4 cathode material for lithium-ion batteries

LiNi0.5Mn1.5O4 cathode material has been synthesized by a combined coprecipitation-hydrothermal method followed by high-temperature calcination. Ti doping was achieved via acetic acid glacial assisted sol-gel method by using titanium(IV) butoxide as Ti source. The effects of different Ti doping contents on the structure, morphology and electrochemical properties of LiNi0.5Mn1.5O4 materials were systematically investigated. The as-synthesized samples were characterized by XRD, FT-IR, SEM, TEM, XPS, EIS and constant-current charge/discharge test. It is found that although Ti doping can effectively inhibit the formation of LixNi1-xO impurity phase, excessive Ti doping results in the appearance of Li2TiO3 secondary phase. SEM observation shows that Ti doping can improve the crystallinity of particles, and particle size shows a gradual increasing trend with Ti doping content. LiNi0.5Mn1.5O4 material doped with 3% Ti shows high phase purity and crystallinity, appropriate Mn3+ content and particle size with uniform distribution, thereby leading to its optimal electrochemical performance. Its discharge capacity at 10 C rate can reach 127.3 mA h g−1, and capacity retention rate can reach 91.7 % after 200 cycles at 1C and 25 °C. Post-mortem analysis shows that appropriate Ti doping can efficiently ameliorate electrolyte decomposition and other side reactions, thus leading to the formation of thinner SEI/CEI layer on electrode surface, and then better cycling performance achieved.

Correlation between phase composition and exchange bias in CoFe/MnN and MnN/CoFe polycrystalline films

Magnetic properties and phase composition of both MnN/CoFe (MnN at top of bilayer) and CoFe/MnN films (MnN at bottom of bilayer) bilayers through annealing at various temperatures (Ta = 300-450 °C) and then cooling to room temperature under the application of an external magnetic field of 1.5 kOe are compared. The exchange bias field (HE), the magnitude of magnetic hysteresis loop shift, of the studied films is highly related to phase composition of antiferromagnetic (AF) layer. The increase of HE with increasing Ta in the range of 300-375 °C possibly results from the improvement of magnetocrystalline anisotropy of AF related to the promoted crystallinity and stress relaxation of tetragonal face-centered θ-MnN phase. The reduction of HE at higher Ta is due to the decreased volume fraction or disappearance of θ-MnN phase and the formation of impurity phases, such as Mn4N and Mn. The induction of impurity phases is possibly related to the diffusion of part of N out of MnN phase at higher Ta. Higher HE for CoFe/MnN than MnN/CoFe at Ta = 300-375 °C might be attributed to larger amount and higher degree of stress relaxation for θ-MnN phase. For CoFe/MnN film annealed at 375 °C, the highest HE = 562 Oe is attained, and the corresponding interfacial exchange energy of 0.47 mJ/m2 in this study is comparable to that reported by Meinert et al. [Phys. Rev. B 92, 144408 (2015)].

Electrical properties and positron annihilation studies of nano-crystalline CoLaxFe2−xO4 prepared by ceramic method

The samples of nano-crystalline CoLaxFe2−xO4 were prepared by ceramic method. The results show the formation of cubic inverse spinel phase for all CoLaxFe2−xO4 samples in addition to impurity phase formation of LaFeO3 for high La content samples. The crystallite sizes for all samples are almost 30 nm. The dielectric measurements show that the presence of La enhances the values of dielectric constant at high temperature, demonstrating Debye relaxation. The DC electric resistivity decreases with La content, suggesting that the conduction phenomenon in these samples is due to hopping of charge carriers. The positron annihilation spectroscopy shows that the large size defects decrease with La for low content samples. However, at higher La content (x = 0.25), the agglomeration of the defects is the dominant process. The CoLa0.25Fe1.75O4 sample shows a different type of defect from other samples. The high electrical resistivity and low tan δ recommend that these samples can be used in power applications that require negligible eddy currents.

Magnetic property improvement of melt spun LaCo5-based nanocomposites with Y, Fe and C substitutions

Magnetic properties, crystal structure, and microstructure of La1-xYxCo4.7-yFeyC0.3 alloys (x = 0–1; y = 0–0.5) prepared by melt spinning are reported. Very low coercivity (iHc) of 0.2 kOe is found for LaCo4.7C0.3 ribbon due to the existence of large amount of magnetically soft LaCo13 (1:13) and La2Co7 (2:7) phases. Interestingly, Y substitution for La was found effective in suppressing the formation of impurity phases and stabilizing 1:5 phase. Y entrance into 1:5 phase increases the Curie temperature and improves saturation magnetization (4πMs) and magnetocrystalline anisotropy field (Ha), simultaneously. Fine microstructure observed for all studied samples due to C-doping contributes to high iHc and good squareness of demagnetization curve. The stabilized 1:5 phase and increased 4πMs with Y substitution for La and fine microstructure due to C-doping give rise to significant improvement of the permanent magnetic properties. The magnetic properties of LaCo4.7C0.3 ribbons can be enhanced to remanence (Br) = 4.2–5.4 kG, iHc = 8.0–14.5 kOe, (BH)max = 3.6–6.6 MGOe for x = 0.25–1. Finally, for alloy with x = 0.5, Fe-doping could further improve magnetization and (BH)max of La0.5Y0.5Co4.7-yFeyC0.3 ribbons, from Br = 4.4 kG and (BH)max = 4.4 MGOe for y = 0 to Br = 4.7–4.8 kG and (BH)max = 5.0–5.1 MGOe for y = 0.3–0.4, respectively. The result of this study provides a significant way to largely improve magnetic performance of isotropic LaCo5-based nanocomposites.

Effect of vacancies on thermoelectric properties of β-CuAgSe studied by positron annihilation

CuAgSe is a promising thermoelectric material due to its superionicity. In this work, β-Cu1−xAg1−ySe (x = 0, 0.02, and 0.04; y = 0, 0.02, and 0.04) samples are synthesized by solid-state reaction method. The vacancies in samples are characterized by positron annihilation spectroscopy. Thereafter, the effects of vacancies on thermoelectric properties are investigated. The positron annihilation results reveal that Ag vacancies exist in the Ag-deficient samples (β-CuAg0.98Se and β-Cu0.98Ag0.98Se) but also in the Cu-deficient samples (β-Cu0.96AgSe and β-Cu0.98AgSe). For the Cu-deficient samples, the existence of Ag vacancies is attributed to the formation of impurity phases. For the nonstoichiometric samples, the vacancies are responsible for the decrease in the Seebeck coefficient in the temperature range from 300 to 400 K. However, for β-CuAgSe, no decrease in the Seebeck coefficient is observed due to the lack of extra holes, and electrons are still the majority carriers. For CuAgSe, the ZT value is mainly determined by the Seebeck coefficient. Therefore, for the nonstoichiometric samples, the ZT value reduces drastically with increasing temperature and drops to nearly zero at 400 K. In contrast, with the temperature increasing from 300 to 450 K, the ZT value of β-CuAgSe goes up from 0.4 to 0.5.

Immobilization of CeO2 using single-phase zirconolite and the chemical stability analysis

In this study, zirconolite-based ceramic powder was firstly fabricated from combustion reaction route. CeO2 was introduced as the surrogate of tetravalent actinides, which was directly immobilized by the single-phase zirconolite waste matrice. The results demonstrate that the crystalline incorporation of CeO2 is highly depended on the sintering temperature. 10 wt% CeO2 was directly immobilized into the zirconolite crystal structure under 1250 °C sintering, where Ce concurrently occupies the Ca and Zr sites. Higher CeO2 incorporation (15–25 wt%) leads to the formation of Ce-rich impurity phase and phase transformation from 2M-zirconolite to 3T-zirconolite. The Ce-bearing zirconolite waste forms exhibit the highest density and hardness after sintering at 1400 °C for 12 h. The aqueous durability was evaluated, where the 42 days LRCe values are 1.68 × 10–6 and 6.85 × 10–6 gm−2d−1 before and after the leachate treatment using nitric acid.

Preparation of chabazite zeolite membranes by a two-stage varying-temperature hydrothermal synthesis for water-ethanol separation

Pure and thin chabazite zeolite membranes were successfully prepared on macroporous symmetrical stainless steel supports by a two-stage varying-temperature hydrothermal synthesis. The morphologies and pervaporation properties of chabazite zeolite membranes were greatly influenced by synthesis times and temperatures at each stage. XRD and SEM characterization results showed that a high temperature at the first stage could effectively avoid the formation of MER impurity phase. The optimal crystallization condition was 150 °C for 10 h at the first stage and 100 °C for 5 h at the second stage. Pervaporation results presented that the precursor gel containing a certain amount of chabazite seed crystals was beneficial to prepare high-performance chabazite zeolite membranes. Well reproducible chabazite zeolite membranes displayed an average permeation flux of 6.25 kg m−2 h−1 and an average separation factor of 1950 for a water/ethanol (10/90 wt%) mixture at 75 °C. Besides, as-synthesized membranes had a good stability for separation of a water/ethanol (30/70 wt%) mixture at 75 °C for 10 d test period, indicating that chabazite zeolite membranes had a promising dehydration application even in water-rich organic solvents.

Boosting the Activity of BaCo0.4Fe0.4Zr0.1Y0.1O3−δ Perovskite for Oxygen Reduction Reactions at Low‐to‐Intermediate Temperatures through Tuning B‐Site Cation Deficiency

AbstractDoped perovskite oxides with the general formula of AxA′1−xByB′1−yO3 have been extensively exploited as the cathode materials of solid oxide fuel cells (SOFCs), but the performance at low‐to‐medium temperatures still needs improvement. BaCo0.4Fe0.4Zr0.1Y0.1O3−δ (BCFZY) has been recently reported to show promising oxygen reduction reaction (ORR) activity under SOFCs' operating conditions. Here, it is reported that the activity of BCFZY can be further boosted via introducing a slight B‐site cation deficiency into the oxide lattice, and such an improvement is assigned to an increase in oxygen mobility that brings enhancement in both surface exchange and bulk diffusion kinetics. Specifically, materials with the nominal composition of Ba(Co0.4Fe0.4Zr0.1Y0.1)0.975O3−δ and Ba(Co0.4Fe0.4Zr0.1Y0.1)0.95O3−δ show significantly improved activity for ORR at reduced temperatures with the area specific resistances of 0.011 and 0.024 Ω cm2 at 600 °C, as a comparison of 0.042 Ω cm2 for the cation stoichiometric BCFZY. Excessive B‐site deficiencies, however, lead to the formation of impurity phases, which cause a block for charge transfer and, consequently, a reduction in electrode performance. Introducing a B‐site cation deficiency is a promising way to optimize the activity of perovskite oxides for ORR at reduced temperatures, but the degree of deficiency shall be carefully tuned.

Facile and seed-direct synthesis of pure EUO zeolite with enhanced catalytic performance

The preparation of pure EUO zeolite under conventional conditions usually takes more than three days, limiting the application of the EUO zeolite. It is widely acquainted that the seed-assisted synthesis of zeolites without organotemplates is inexpensive, environmentally-friendly and lead to Al-rich products. However, synthesis with EUO seeds in the absence of organic-templates always leads to the formation of impurity phases. In this work, EUO zeolite (s-EUO) is successfully obtained by seed-directed synthesis without organotemplates. This is the first seed- directed synthesis of pure EUO zeolite with special Al source. Physicochemical characterization results show that the synthesized s-EUO zeolite exhibits high crystallinity and high specific surface area, and contains uniform crystals and plenty acidic sites. The s-EUO crystallization (by this method) occurs in a considerably shorter time (18 h) and in a more mild condition (160 °C, static state), compared to that of the conventional EUO zeolites (c-EUO, 72 h at 180 °C, at rotation) in the presence of organotemplate. Moreover, the catalytic performance of the H-form of the s-EUO zeolite is enhanced to that of the c-EUO zeolite for m-xylene isomerization, confirming the NH3-TPD results.

Spark Plasma Sintering of Lithium Aluminum Germanium Phosphate Solid Electrolyte and its Electrochemical Properties.

Sodium superionic conductor (NASICON)-type lithium aluminum germanium phosphate (LAGP) has attracted increasing attention as a solid electrolyte for all-solid-state lithium-ion batteries (ASSLIBs), due to the good ionic conductivity and highly stable interface with Li metal. However, it still remains challenging to achieve high density and good ionic conductivity in LAGP pellets by using conventional sintering methods, because they required high temperatures (>800 °C) and long sintering time (>6 h), which could cause the loss of lithium, the formation of impurity phases, and thus the reduction of ionic conductivity. Herein, we report the utilization of a spark plasma sintering (SPS) method to synthesize LAGP pellets with a density of 3.477 g cm−3, a relative high density up to 97.6%, and a good ionic conductivity of 3.29 × 10−4 S cm−1. In contrast to the dry-pressing process followed with high-temperature annealing, the optimized SPS process only required a low operating temperature of 650 °C and short sintering time of 10 min. Despite the least energy and short time consumption, the SPS approach could still achieve LAGP pellets with high density, little voids and cracks, intimate grain–grain boundary, and high ionic conductivity. These advantages suggest the great potential of SPS as a fabrication technique for preparing solid electrolytes and composite electrodes used in ASSLIBs.

Effects of Al content on the oxygen permeability through dual-phase membrane 60Ce0.9Pr0.1O2--40Pr0.6Sr0.4Fe1-Al O3-

Ceramic dual-phase oxygen transport membranes with the composition of 60wt.% Ce0.9Pr0.1O2-{\delta}-40wt.%Pr0.6Sr0.4Fe1-xAlxO3-{\delta} (x = 0.05, 0.1, 0.2, 0.3, 0.4, 0.6, 0.8, 1.0) (60CPO-40PSF1-xAxO) based on 60Ce0.9Pr0.1O2-{\delta}-40Pr0.6Sr0.4FeO3-{\delta} doped Al was successfully synthesized through a modified Pechini method. Crystal structure, surface microtopography and oxygen permeability are investigated systematically. The cell parameters of perovskite phase first increased and then decreased with the increase of Al content, which is related to the radius of the Al3+ and the formation of impurity phase. As x ranges from 0.1 to 0.8, the oxygen permeability of the materials first increases and then decreases, and the maximum value of oxygen permeation rate for 60CPO-40PSF1-xAxO membranes with 0.4mm thickness at 1000 {\deg}C is 1.12 mL min-1 cm-2 when x = 0.4. XRD measurements revealed high temperature stability and CO2-tolerant property of the dual-phase composites. The partial replacement of Fe$^{3+}$/Fe$^{4+}$ by Al$^{3+}$ causes the material not only to exhibit good stability, but also to increase the oxygen permeability of the membranes.

Magnetoelectric and HR-STEM investigations on eutectic CoFe2O4–Ba1–xSrxTiO3 composites

Multiferroic Ba1–xSrxTiO3–CoFe2O4 (x = 0.03, 0.05) composites with rarely investigated 3-3 connectivity were prepared by eutectic crystallization in an optical floating zone furnace. High-resolution scanning transmission electron microscopy investigations of the CoFe2O4–BaTiO3 interface revealed an almost perfect connection between both components. These micrographs also showed that the impact of post-annealing in air was much larger than expected and resulted in formation of small BaTiO3 inclusions in the CoFe2O4 phase. The magnetoelectric coefficient αME was studied in detail with respect to its dependence on the static magnetic field, the frequency of the driving AC-field and temperature. Furthermore, the influence of different growth rates (5, 10 and 20 mm h−1), chemical composition, sample thickness and the alignment of electrical polarization and magnetic field (collinear or vertical) on the magnetoelectric properties were studied. The largest value of αME = 1.3 mV Oe−1 cm−1 was found for a sample grown at 5 mm h−1. For even slower growth rates, a higher Sr content was required to avoid the formation of impurity phases leading to a decrease of αME.

Apparent activation energy of multicomponent transition metal oxalates to probe synthesis of battery precursor materials

In this study the apparent activation energy of pure and multicomponent transition metal oxalate coprecipitation reactions were experimentally measured via time dependent extinction of light passing through the reaction solution. These measurements provide a quantitative descriptor of the influence of the relative transition metal composition on the nucleation and growth processes of the precipitates. The resulting crystal structures of the synthesized precursors were also determined and put into the context of the measured coprecipitation apparent activation energies, revealing that the apparent activation energy may indicate impurity or secondary phase formation before it was detectable with X-ray diffraction. This paper is the first report of using apparent activation energies to investigate battery precursor coprecipitation reactions, and these methods should be extendable to chemistry for coprecipitation of many multicomponent transition metal particles which have applications in multiple fields including energy storage materials.

The investigation of various type irradiation effects on aluminum nitride ceramic

The paper presents the results of a study of the effect of proton and ion radiation on structural changes in nitride ceramics, which have a high potential for using as a structural material for GenIV nuclear reactors. Proton beams with an energy of 1.5 MeV and low-energy helium (He2+) and carbon (C2+) ions with an energy of 40 keV were used, to simulate defect formation and to estimate ceramics radiation resistance. According to the data obtained, it has been established that aluminum nitride ceramics have high radiation resistance to the effects of proton radiation. While under irradiation with C2+ ions, the observed degradation of the surface layer is due to the accumulation of carbon in the structure with the subsequent formation of impurity carbide inclusions. It is established that the accumulation of slightly soluble ions of helium and carbon in the structure of the surface layer leads to an increase in the strain and distortion of crystal lattice due to introducing ions into the interstitial lattice and breaking chemical and crystalline bonds. As a result of studying the optical characteristics of irradiated samples, it was found that the decrease in absorption spectra intensity for samples irradiated with helium and carbon ions is due to a change in the interplanar distances as a result of the migration of defects along the structure with the subsequent formation of impurity inclusions. The formation of impurity phases and a high concentration of defects in the structure of ceramics leads to a sharp decrease in performance.

Evaluation of properties of spark plasma sintered Ti3SiC2 and Ti3SiC2/SiC composites

Abstract The powder mixtures of Ti, Si, TiC and Al were sintered to synthesize Ti3SiC2 and Ti3SiC2/SiC by spark plasma sintering (SPS) method. Single phase Ti3SiC2 and Ti3SiC2/SiC composites were obtained by sintering Ti/1.1Si/2TiC/0.2Al and 2.2Si/3TiC/0.2Al at 1400 °C, for 15 min, under a pressure of 50 MPa, respectively. The reduction of Al and Si contents in the starting powder mixture led to the formation of TiC impurity phase. X-ray diffraction (XRD) and Rietveld analyses were used to evaluate the phase constituents. The main objective of this study was to reveal the properties of single phase Ti3SiC2 and to evaluate the development of the mechanical and tribological properties of Ti3SiC2/SiC comprehensively. The results indicated that the SiC in situ reinforced Ti3SiC2 composites exhibited higher hardness, fracture toughness and wear resistance compared to single phase Ti3SiC2.

Degradation in fundamental characteristic features of Bi-2212 superconducting ceramic material with Sr/Ti partial substitution

The present work investigates the vital differentiations in some basic characteristic properties including the crystallinity quality, flux pinning mechanism, superconducting, dc electrical features, grain boundary coupling problems and strength of connection between the superconducting grains in the poly-crystallized Bi2.1Sr2.0−xTixCa1.1Cu2.0Oy cuprate ceramic materials with the partial aliovalent substitution of Sr2+ impurities for the Ti4+ foreign additives in the crystal system. All the materials are prepared by the standard solid-state reaction method, and the characterization of samples produced is thoroughly performed by the typical experimental measurements such as dc electrical resistivity over the temperature, critical current density and powder X-ray diffraction investigations. It is obvious that all characteristic properties tend to diminish constantly with the augmentation of the aliovalent Sr/Ti partial replacement level, and in case of x = 0.10 they reach the global minimum values. To illustrate, the low Bi-2212 superconducting phase diverges from the stabilization because of new induced permanent crystal structure (crystallinity) problems such as the voids, porosity, defects, texturing, cracks, grain boundary coupling problems, grain alignment distributions, stress raisers, omnipresent flaws and crack initiation sites in the crystal system. Besides, the presence of Ti impurities leads to the formation of new impurity phases related to very low superconducting and characteristic TiO2 phase, being favored by either the decrement of c lattice cell parameter or increment of a-axis length. The similar findings are observed in the temperature dependent electrical resistivity measurements. Namely, the electrical resistivities at the normal state are found to increase dramatically from about 74.75–180.47 mΩcm whereas the offset and onset critical temperature values are recorded to diminish from 82.11 K (for the pure sample) to 50.52 K (for the sample prepared with x = 0.10 substitution level) and 84.03–75.14 K, respectively, with the enhancement in the substitution level. Likewise, the Sr/Ti partial replacement affects negatively not only the thermal fluxon motions of correlated two-dimensional pancake vortices but also the ability and strength of vortex lattice period, elasticity, effective and active energy barriers for the flux pinning centers in the Bi-2212 superconducting crystal lattice. In this respect, the Sr/Ti partial substitution mechanism is ploughed to improve the fundamental characteristic features.

Tailoring Catalytic Properties of CuMgAl Hydrotalcites for Selective hydrogenolysis of Cellulose

AbstractThe structure and catalytic properties of CuMgAl ternary hydrotalcites were tailored by adjusting MII/MIII molar ratios. Due to the Jahn‐Teller distortion effect, co‐crystallized impurity phase assigned to Cu2(NO3)(OH)3 was formed for the catalyst with high MII/MIII molar ratio. The formation of impurity phase resulted in the significant change of morphologies and low dispersion of copper species in the hydrotalcites. Nevertheless, the corresponding catalyst exhibited great catalytic proformance in term of ethylene glycol (EG) selectivity for the hydrogenolysis of cellulose. Besides, higher activity was obtained over the catalysts with higher content of Mg due to an increase of the alkalinity.

A silica-confined strategy for completely atomic level Fe(II)-N-C catalysts with a non-planar structure toward oxygen reduction reaction

Constructing pure iron-nitrogen-carbon (Fe-N-C) catalysts without Fe-based particles for the oxygen reduction reaction (ORR) is extremely important to design efficiently next-generation non-platinum electrocatalysts for fuel c ells. Herein, we propose a silica-confined strategy for the pure Fe–N–C catalysts without Fe-based impurity phases, through post grafting iron and nitrogen atoms onto the surface of a carbon black. In an alkaline media, compared with the conventional Fe-N-C catalyst without silica, the silica-confined catalyst exhibits a remarkably improved catalytic activity and durability for the ORR, which are even higher than those obtained by a commercial Pt/C. The superior activity can be attributed to the inclusive Fe-N-C moieties with a non-planar Fe(II)-N4 structure, raised by an interaction between the disordered carbon black and pyrrolic N4-plane in this catalyst. The introducing of silica can not only contribute to the generation of the active Fe(II)-N4 moieties but also suppress the formation of Fe-based impurity phases. This work may open a door to the rational design and facile synthesis of highly active non-precious metal electrocatalysts towards the ORR.

Surfactant-mediated solvothermal synthesis of CuSbS2 nanoparticles as p-type absorber material

The novel chalcostibite CuSbS2 had gained unique attention due to their dynamic nature as less toxic, cost-effective and earth abundant materials for the synthesis of an absorber layer in solar cell application. Herein, a facile and effective solvothermal method was used to enhance the sphere-like grain growth in the presence of polyvinylpyrrolidone (PVP) along with other precursor’s, followed by the deposition of CuSbS2 thin films using drop casting method. The synthesized nanoparticles and the deposited films were characterized for their structural, morphological, optical and electrical properties using different characterization techniques. X-ray diffraction (XRD) and Raman analysis revealed that as the amount of PVP increased, the crystallinity improved and the impurity phase formation reduced. High-resolution transmission electron microscope (HRTEM) with reduced crystallite size in the range of 2–5 nm and field emission scanning electron microscope (FESEM), exhibited sphere-shaped grains indicating the effect of PVP as surfactant for the growth of CuSbS2 nanomaterials. The average elemental composition of the nanoparticles had been determined using EDX analysis, and the result yielded Cu rich in all the samples. Optical studies using UV–Vis-NIR diffuse reflectance spectroscopy revealed that obtained CuSbS2 nanoparticles were having the absorption in the entire visible region and the direct band gap energy was in the range of 1.25 eV to 1.53 eV and that of photoluminescence spectrum gave the emission in the near IR region. The hall measurement studies showed that the deposited CuSbS2 films exhibited p-type conductivity. Devices were fabricated with the configuration of FTO/n-TiO2/p-CuSbS2/Ag, and the electrical properties were studied by recording the current- voltage (I-V) characteristics of the heterojunction device structures.