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Chalcopyrite CuFeS2 can be considered a promising thermoelectric material when its lattice thermal conductivity κ lat is successfully reduced. We attempted to obtain fine microstructures of Zn-doped CuFeS2 to reduce κ lat while keeping its high power factor. A submicron scale grain size was achieved, and κ lat was reduced by 47%, though the electrical resistivity was significantly increased. According to phonon calculations, we propose that a thin film form is a promising candidate to achieve further attenuation of κ lat of CuFeS2 without sacrificing electrical properties via precise control of thickness.

This paper researches the effectiveness of heap leaching for processing the sulfide raw materials in Murmansk Oblast. It studies the kinetics of how metals are extracted into the solution, as well as the peculiarities of chalcopyrite dissolution. The paper shows that leaching destroys the grains, making them into fine particulate matter, which ultimately jeopardizes solution filtering. Use of recycled solution makes the leaching process more cost-effective.

The efficiency potential of chalcopyrite and kesterite solar cells including CIGSe (CuInGaSe2), CIGS (CuInGaS2), CZTS (Cu2ZnSnS4) and CZTSSe [Cu2ZnSn(S,Se )4] solar cells is discussed based on external radiative efficiency (ERE), open-circuit voltage loss, fill factor loss, non-radiative recombination and resistance loss. CIGSe cells achieve efficiency potential of 26.8% and 27.5% by improving the ERE from around 1% to 10% and 20%, respectively. CIGS and CZTS(Se) cells achieve the efficiency potential of 25% and 22%, respectively, by improvement in ERE from around 1 × 10−4% to 3%–5%. The effects of non-radiative recombination and resistance loss upon the properties of wide-bandgap CIGSe, CIGS and CZTS(Se) cells are discussed. In the case of wide-bandgap CIGSe cells, lattice mismatching between the buffer layer and CIGSe active layer and deep-level defects are thought to originate from non-radiative recombination loss. CIGS and CZTS(Se) cells are shown to have lower ERE and higher resistance loss compared to that of CIGSe cells.

The partial replacement of Cu by Ag in Cu(In,Ga)Se2 thin-film solar cells is strategically interesting to achieve smooth devices with high conversion efficiencies. Yet, the industrial exploitation requires further understanding of the deposition process and control of the absorber layer properties. In this study, three-stage co-evaporation of (Ag,Cu)(Ga,In)Se2 films with [Ag]/([Ag] + [Cu]) contents up to 0.2 was investigated. Deep crevices and voids, sometimes extending down to the rear contact, were found. They mainly occur for high Ag contents and excessive group-I richness during the second stage of the deposition. The formation of cavities is attributed to the segregation of Ag–Se phases and slow Ag diffusion into the chalcopyrite during the deposition. Another identified challenge is the flattening of the desired bandgap grading which is correlated with the Ag content. Optimized process conditions allow fabrication of smooth (Ag,Cu)(Ga,In)Se2 films in a manufacturing-like inline deposition with cell efficiencies up to 20.5%.

This study researched mineralogy characteristics of Jiudingshan Cu-Mo sulphide ore by modern testing instruments, such as scanning electron microscope (SEM), reflected light microscope (RLM), X-ray diffractometer (XRD), and mineral liberation analyzer (MLA). The occurrence of Cu, Mo and other valuable minerals were mainly investigated. Results show that: it contain 0.50% Cu, 0.15% Mo and 7.04% Fe. Forty individual minerals are involved in the ore. Main valuable minerals are molybdenite, chalcopyrite, magnetite, pyrite; main gangue minerals are quartz, feldspar, garnet, calcite, dolomite.Molybdenite, chalcopyrite are finely disseminated in the magnetite,quartz, feldspar, garnet; some are inlayed along other minerals such as idocrase, actynolin.

Chalcopyrite was synthesized with various reaction precursors and solvents, and plate-, rod-, and sphere-like chalcopyrite can be obtained. Our results show that rod-like chalcopyrite has higher discharge capacity, better rate capacity and cycle performance than others.

In the north of Chile, due to water shortages, the depletion of oxide ores and the abundance of chalcopyrite ore, mining industry is searching for sustainable hydrometallurgy processes that can use alternative water resources. The leaching process must enhance the dissolution of copper sulphide ore that are refractory to conventional leaching. This paper reports a study on the effect of addition of chloride ion using seawater and discard brine in the agglomeration stage of a secondary copper sulphide ore. The effect of curing time on the same ore also is reported. The leaching tests have been carried out in column irrigated with raffinate under ambient conditions. A size distribution with a P80 of 17 mm is used. A maximum of 72% of copper extraction is obtained using discard brine and 68% using seawater. The use of discard brine and seawater are favorable in all the tests performed. Through an Analysis of Variance (ANOVA), it is determined that the curing time has the highest contribution (92.37%) on the percentage of copper extraction.

The first-principles studies of structural, electronic and elastic properties have been performed for chalcopyrite-type (Cu1−x Li x )GaS2 solid solutions with x = 1/16, 1/8, 1/4, and 1/2 using general gradient approximations (GGA) with ultrasoft and norm-conserving pseudopotentials based on density functional theory. The band-gap energies have been also calculated using nonlocal screened hybrid density functional HSE06 for the structures optimized by GGA approximations. The results are compared with reported experimental data and the results of (Cu1−x Li x )InS2 system calculated by the similar method. The Li-content (x) dependence of experimental band-gap energies in (Cu1−x Li x )GaS2 system is explained qualitatively where the band-gap energy increases with increasing Li content, x. The pronounced experimental Li content dependence of the tetragonal lattice parameters has been reproduced semi-quantitatively in which the lattice constant c of tetragonal (Cu1−x Li x )GaS2 decreases whereas the lattice constant a increases with increasing Li content. A possible origin of the peculiar Li content dependence of the lattice parameters is proposed from the calculated difference in Young's modulus along the a and c axes, which suggests that the bonding interaction within the c-plane is stronger than that along the c-axis in the (Cu1−x Li x )GaS2 system.

CIGS nanoink has synthesized from molecular precursors of CuCl, InCl3, GaCl3 and Se metal heat up 240 °C for a half hour in N2-atmosphere to form CIGS nanoink, and then deposited onto substrates of soda-lime glass (SLG). This work focused on CIGS nanocrystals, indicates their synthesis and applications in photovoltaic devices (PVs) as an active light absorber layers. in this work, using spin-coating to deposit CIGS layers (75 mg/ml and 500 nm thickness), without selenization at high temperatures, were obtained up to 1.398 % power conversion efficiency (PCE) at AM 1.5 solar illumination. Structural formations of CIGS chalcopyrite structure were studied by using x ray diffraction XRD. The morphology and composition of CIGS were studied using scanning electron microscopy SEM.

The methodology mainly includes four parts: pre-field studies, field investigations, laboratory analysis, and data analysis and interpretation. Laboratory analysis to be carried out is petrographic analysis and ore microscope. Research methods relating to petrography analysis studies and ore mineral that will be evaluated for genetic models and the origin of copper deposition mineralization. The rock units in the study area are differentiated based on the type of lithology, uniformity of rocks, the distribution of rocks and rock geometry found in one region and the stratigraphic position of the units below it or above it. In general, the stratigraphy of the research area is divided into 3 rock units that can be seen on the geological map, sequences from old to young, namely lithology of Sandstone Unit, Dense Tuf Unit, and Andesite Unit. ore mineralization generally occurs as a massive form, vein. Pyrite, enargite, luzonite, sphalerite, covellite, chalcopyrite, tennatite and tetrahedtrite are common sulfides and sulfosal minerals

The efficiency potentials of future generation solar cells such as wide bandgap chalcopyrite, Cu2ZnSnS4 (CZTS), Cu2ZnSn(S,Se)4 (CZTSSe), multi quantum well (MQW) and quantum dot (QD) solar cells are discussed on the basis of external radiative efficiency (ERE), open-circuit voltage loss, fill factor loss, and nonradiative recombination losses. CZTS and CZTSSe solar cells have efficiency potentials of more than 20% owing to the improvement in ERE from about 0.001 to 1%. MQW and QD cells have efficiency potentials of 24.8%, and 25.8% owing to the improvement in ERE from around 0.01 to 0.1%, and 1%, respectively. In this paper, the effects of nonradiative recombination on the properties of future generation solar cells are discussed.

The electronic structure and magnetic properties of chalcopyrite Zn(Sn,TM)As2 and (Zn,TM)SnAs2 have been investigated by the Korringa–Kohn–Rostoker method combined with the coherent potential approximation within the local spin density approximation, where TM denotes a 3d transition metal element. We find that the half-metallic and high-spin ferromagnetic state can be obtained in Zn(Sn,V)As2, Zn(Sn,Cr)As2, Zn(Sn,Mn)As2, (Zn,V)SnAs2, and (Zn,Cr)SnAs2. The calculated result of Zn(Sn,Mn)As2 is in good agreement with the experimentally observed room-temperature ferromagnetism if we can control selective Mn doping at Sn sites. In addition, (Zn,V)SnAs2 and (Zn,Cr)SnAs2 are predicted to exhibit high-Curie-temperature ferromagnetism.

The Artisanal Small Gold Mining in Sumbawa has been processing gold with mercury (Hg), which poses a serious threat to the mining and global environment. One method of gold processing that does not use mercury is by gravity method. Before processing the ore first performed an analysis of Mineragraphy and analysis of compound with XRD. Mineragraphy results show that gold is associated with chalcopyrite and covelite and is a single particle (native) on size 58.8 μm, 117 μm up to 294 μm. characterization with XRD shows that the Sumbawa Gold Ore is composed of quartz, pyrite, pyroxene, and sericite compounds. Sentrifugation is one of separation equipment of gravity method to increase concentrate based on difference of specific gravity. The optimum concentration result is influenced by several variables, such as water flow rate and particle size. In this present research, the range of flow rate is 5 lpm and 10 lpm, the particle size - 100 + 200 mesh and -200 +300 mesh. Gold concentration in concentrate is measured by EDX. The result shows that the optimum condition is obtained at a separation with flow rate 5 lpm and a particle size of -100 + 200 mesh.

Hydrophobic polystyrene nanoparticles bearing thiazole groups named HNP were used as collectors to improve recovery of microfine chalcopyrite in flotation. HNP adsorbs onto microfine particles selectively, which were modified hydrophobically to induce flotation effectively. Particle size and scanning electron microscope analysis for HNP show that HNP is a spherical nano particles with small size, uniform distribution and good dispersion. Infrared spectrum analysis for HNP proved that functional monomer 2-mercapto styrene acrylic thiazole was bonded chemically onto styrene. Flotation test results indicate that HNP is the right collector of chalcopyrite. Especially, the recovery of chalcopyrite is higher than 95% in neutral and acid media. FTIR results reveal that the flotation selectivity of collector HNP is due to strong chemical absorption onto chalcopyrite surface. Zeta potential analysis shows that the zeta potential of chalcopyrite decreased more quickly after interaction with HNP with the increase of pulp pH value, confirming that collector HNP is an anionic collector. Scanning electron microscope conform that HNP has good selective adsorption on chalcopyrite.

The Cu–In–Zn–Se thin film was synthesized by changing the contribution of In in chalcopyrite CuInSe2 with Zn. The XRD spectra of the films showed the characteristic diffraction peaks in a good agreement with the quaternary Cu–In–Zn–Se compound. They were in the polycrystalline nature without any post-thermal process, and the main orientation was found to be in the (112) direction with tetragonal crystalline structure. With increasing annealing temperature, the peak intensities in preferred orientation became more pronounced and grain sizes were in increasing behavior from 6.0 to 25.0 nm. The samples had almost the same atomic composition of Cu0.5In0.5ZnSe2. However, EDS results of the deposited films indicated that there was Se re-evaporation and/or segregation with the annealing in the structure of the film. According to the optical analysis, the transmittance values of the films increased with the annealing temperature. The absorption coefficient of the films was calculated as around 105 cm−1 in the visible region. Moreover, optical band gap values were found to be changing in between 2.12 and 2.28 eV depending on annealing temperature. The temperature-dependent dark- and photo-conductivity measurements were carried out to investigate the electrical characteristics of the films.

ZnSnAs2 thin films were prepared by molecular beam epitaxy (MBE) on semi-insulating (001) InP substrates using the same growth conditions as previously reported. High-resolution X-ray diffractometry (HRXRD) and Raman spectroscopy studies suggest the presence of both the chalcopyrite and sphalerite phases. The transport properties were measured from 5 K up to room temperature. We observed a pronounced peak in the Hall coefficient temperature dependence curve at ~130 K, similar to those observed only from chalcopyrite-phase bulk ZnSnAs2 in earlier studies. A hole concentration of p = 5.98 ×1018 cm-3, hole mobility of µ= 23.61 cm2/(Vs) and resistivity of ρ= 4.43 ×10-2 Ωcm were obtained at room temperature.

In this study, the material properties of compositionally graded and homogeneous Cu(In1−xGax)(Se1−ySy)2 (CIGSSe) alloys were compared. The chalcopyrite alloys were synthesized by the chemical reaction of sputtered copper–indium–gallium metallic alloys to a H2Se/H2S/Ar gaseous ambient. The temperature profiles during heating and cooling, gas concentrations, pressures and reaction periods were varied in order to produce two main classes of films, namely (i) compositional-graded absorbers with steep gallium and/or sulfur gradients and (ii) homogeneous absorbers with uniform elemental distributions through the entire depth of the films. The respective CIGSSe films were coated with standard buffer and window layers in order to evaluate the influence of the absorber quality on the device characteristics of completed photovoltaic devices. The findings from these studies clearly indicated that a better understanding of the CIGSSe film formation process led to absorber material with greatly improved material properties. It was also demonstrated that the conversion efficiencies of devices produced with an industrial-scale two-step growth technology is approaching that of multi-source co-evaporation processes.

The reaction of dc sputtered metallic CuIn alloys to a reactive H2Se/Ar/H2S gaseous atmosphere is an attractive industrial production process to produce CuIn(Se,S)2 chalcopyrite absorber films for applications in photovoltaic modules. However, the obvious technological advantages of this deposition technology are overshadowed by growth-related anomalies such as the separation or at least partial separation of the ternary phases (i.e. CuInSe2 and CuInS2) during the high temperature selenization/sulphurization of the metallic alloy. This in turn prevents the effective band gap widening of the semiconductor alloys in order to achieve open-circuit voltages in excess of 600 mV, which is a critical prerequisite for the optimal performance of thin film solar modules. In this contribution, the material properties of homogeneous single-phase CuIn(Se,S)2 alloys are discussed, produced with a novel two-stage deposition process.

Homogeneous single-phase Cu(In0.75Ga0.25)(Se1−ySy)2 alloys were prepared by the reaction of magnetron sputtered CuIn0.75Ga0.25 precursors to a H2Se/Ar and H2S/Ar gaseous atmosphere under well-defined experimental conditions. X-ray diffraction analysis of the films showed characteristic chalcopyrite peaks with a high degree of symmetry, indicative of homogeneous rather than compositionally graded material. Glancing incident angle x-ray diffraction revealed virtually no variation in the lattice parameters through the entire depth of the alloys. X-ray photoelectron spectroscopy depth profiling confirmed the homogeneous distributions of the respective elements through the entire depth of the pentenary semiconductor alloy under optimized selenization/sulfurization conditions.

Thin film CuInSe2 chalcopyrite semiconductors have been prepared on glass substrates by means of two-stage process. The structural properties and atomic compositions of films were determined by energy-dispersive analysis of x-rays (EDAX) and x-ray diffraction (XRD) measurements. Reflectance and transmittance measurements were performed on the films in the photon wavelength range of 300–2200 nm. The samples used in the measurements have different Cu/In ratios. The reflectance and transmittance spectra were analyzed on the basis of multiple reflection model considering the absorbing film on a non-absorbing substrate and then complex refractive-index n*(E) = n(E) + ik(E) and complex dielectric constant e*(E) = e1(E) + ie2(E) were determined. It has been concluded that the films having higher Cu/In ratios show stronger absorption at low photon energy region than those having lower Cu/In ratios.

In this study, thin films of Cu(In,Ga)Se2 were prepared by the controlled reaction of thermally evaporated InSe/Cu/GaSe precursors with elemental Se vapour in vacuum. We indicate that this classical two-step growth process can be utilized to produce homogeneous single-phase chalcopyrite absorber films with superior structural properties. X-ray diffraction studies indicated that the interplanar spacing d(112) decreases linearly with an increase in the Ga/[In + Ga] atomic ratio due to homogeneous incorporation of gallium into the chalcopyrite lattice. Optical studies revealed the expected systematic increase in the band gap with increasing gallium concentration, once again confirming the monophasic nature of the alloys.

CuIn0.5Al0.5Se2 thin films are successfully prepared using a four-source co-evaporation technique on soda-lime glass substrates held at a substrate temperature of 673 K. Powder x-ray diffraction studies reveal that the films are polycrystalline in nature with chalcopyrite structure. The optical band gaps, calculated from spectral transmittance data, are found to be 1.56 ± 0.02 eV, 1.60 ± 0.02 eV and 1.85 ± 0.02 eV. Considering the three fold optical structure of chalcopyrite compounds, these are attributed to fundamental absorption and additional transitions arising out of crystal field and spin–orbit interactions. The crystal field (ΔCF) and spin–orbit (ΔSO) splitting parameters deduced from these optical band gaps are found to be −0.06 eV and 0.26 eV, respectively. The deformation potential estimated by using a quasi-cubic model is found to be −2.0 eV. The percentage of hybridization of the orbitals was determined using a linear hybridization model. The films are p-type conducting with a room temperature resistivity of 80 Ω cm.

In this study, the reaction kinetics and material properties of polycrystalline CuGaSe2 thin films are reported. The films were prepared by the rapid thermal processing of thermally evaporated glass/Ga/Se/Cu//Ga/Se stacked precursors. In order to gain insight into the chalcopyrite formation process, stacked elemental layers with different Cu/Ga atomic ratios were annealed in an Ar/Se atmosphere under different thermal conditions. For typical annealing temperatures below 600°C, x-ray fluorescence studies indicated that a homogeneous element distribution could only be obtained for stoichiometric or near-stoichiometric samples. Systematic studies indicated that temperatures above 600°C are required in order to enhance the crystallinity and in-depth compositional uniformity of Ga-rich CuGaSe2 thin films. These results also highlighted the structural limitation of high gallium containing chalcopyrite thin films.

In this study, device quality chalcopyrite thin films were prepared by a simple and reproducible two-step growth process. The precursors were deposited by the thermal evaporation of pulverized compound materials from a single crucible onto Mo coated glass substrates at temperatures around 250 °C. The precursors were subsequently reacted in a controlled H2Se/Ar atmosphere at temperatures ranging between 350 °C and 500 °C. X-ray fluorescence studies revealed marginal changes in the overall bulk compositions of the films at the respective reaction temperatures, clearly demonstrating the reproducibility of the growth process. The material quality (i.e., surface morphologies, formation of crystalline phases and in-depth compositional uniformity) of the films was compared at the respective reaction temperatures in order to determine optimum processing parameters.

In this study, device quality chalcopyrite thin films were prepared by the thermal evaporation of pulverized compound materials from a single crucible. The starting materials were heated from ambient temperature to around 1450°C over a period of only 10 min. This `semi-flash' process prevented many of the reported shortcomings of standard flash processes. The final thicknesses and compositions of the chalcopyrite thin films were determined by the predetermined masses of the starting materials. The material quality (i.e. surface morphologies, formation of crystalline phases and in-depth compositional uniformity) of the films was evaluated at substrate temperatures ranging between 250°C and 500°C. From these studies, optimum growth conditions were determined for the deposition of device quality absorber material. The conversion efficiencies of completed glass/Mo/Cu(In,Ga)Se2/CdS/ZnO solar cell devices were correlated against the material quality of the respective absorber films.

In this paper, we demonstrate that device quality chalcopyrite thin films can be produced by a simple and reproducible processing technology. CuInSe2 thin films were prepared by the thermal evaporation of InSe/Cu/InSe precursors, followed by a selenization step in elemental Se vapour. This technique produced large-grained, single-phase CuInSe2 thin films with a high degree of in-depth compositional uniformity. The samples were subsequently sulfurized by the controlled solid-state thermal diffusion of sulfur into the CuInSe2 thin films. The sulfurization temperature, reaction period and position of the elemental sulfur source with respect to the CuInSe2 films were optimized in this study. Under optimized conditions, sulfurization resulted only in a marginal increase in the surface roughness, x-ray diffraction studies confirmed single-phase CuIn(Se, S)2 material and x-ray fluorescence in-depth profiling revealed uniform Cu/In atomic ratios and a systematic increase in the sulfur concentration towards the top surface region of the samples. The increase in bandgap of the absorber layers after sulfurization was also confirmed by an increase in the open-circuit voltage of completed solar cell devices.

In this study, chalcopyrite thin films were prepared by the relatively slow thermal evaporation of compound chalcopyrite materials. The pulverized starting materials were heated from room temperature to a maximum temperature around 1400 °C over a period of 10 min. This growth sequence to a large degree prevented the generally reported problems associated with flash evaporation such as material spitting, inhomogeneous material properties and poor reproducibility. It was also possible to exercise accurate control over the composition of the final films by using predetermined masses of starting materials. Using this approach, it was possible to produce single-phase CuInSe2 thin films at substrate temperatures as low as 350 °C. In contrast, evaporation of CuGaSe2 or Cu(In,Ga)Se2 compounds at low substrate temperatures resulted in final films characterized by the presence of several crystallographic phases. In the latter cases, single-phase material was only obtained after post-growth rapid thermal treatment at 550 °C for 6 min. Solar cell devices fabricated from CuInSe2 and Cu(In,Ga)Se2 absorber films demonstrated favourable results.