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Since the order–disorder phase transition easily occurs during the growth of optoelectronic II–IV–V2 ternary compounds, cation–cation antisites were always considered as the major point defects, while anion-related defects did not attract sufficient attention. In this paper, based on first-principles simulations, the anion–cation antisites are revealed to be comparable to or even dominate over the cation–cation antisites in II–IV–V2 phosphides and arsenides. These antisite defects are predicted to have significant impacts on the optoelectronic properties because they can either act as nonradiative recombination centers or enhance the p-type carrier concentration. Furthermore, based on the calculated defect properties and band alignments, we propose that the alloy ZnGe(P,As)2 can be an efficient p-type solar cell absorber. Its maximal open circuit voltage is effectively enlarged by the low valence band edge; meanwhile, the dominating anion–cation antisites are electrically benign. These results highlight the necessity of considering the anion–cation antisites in the defect engineering of II–IV–V2 phosphides and arsenides. [ABSTRACT FROM AUTHOR]

Chalcopyrite has been extensively utilized for tracing geological processes through its Cu, Fe and S isotopic compositions. However, the matrix-matched reference materials for micro-analysis are lacking. This study focused on assessing the feasibility of a natural chalcopyrite specimen (IGGCcp-1) as a matrix-matched reference material for in situ micro-analysis of Cu, Fe, and S isotopes. Electron probe microanalysis validated the uniform distribution of major elements within chalcopyrite grains, with no evidence of growth zoning. Random spot isotopic measurements using LA-MC-ICP-MS demonstrated remarkable consistency in δ65Cu, δ56Fe and δ34S. These results indicated that the IGGCcp-1 specimen exhibited its suitability as a reference material. Using SN-MC-ICP-MS technique, the δ65Cu value was accurately determined to be 0.43 ± 0.05‰ (2S, N = 30). Furthermore, the δ56FeIRMM-014 and δ57FeIRMM-014 values were recorded as -0.24 ± 0.04‰ (2S, N = 18) and -0.36 ± 0.09‰ (2S, N = 18), respectively. Additionally, the δ34SVCDT measurement, performed with EA-IRMS, yielded a value of -0.28 ± 0.60‰ (2S, N = 10). These precisely measured isotope ratios established the recommended reference values for the IGGCcp-1 sample in future applications of Cu, Fe, and S isotope micro-analysis. [ABSTRACT FROM AUTHOR]

A simple, rapid, economical, and non-enzymatic electrochemical sensor for sensitive determination of hydrogen peroxide (H2O2) was developed based on a physical combination of carbon black (CB) and pure chalcopyrite modified glassy carbon electrode (GCE). Field emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD) were used to evaluated the morphology of the modified electrode. The proposed sensor (CuFeS2-CB/GCE) was investigated electrochemically using cyclic voltammetry (CV), amperometric methods (AP), and electrochemical impedance spectroscopy (EIS). The CuFeS2-CB/GCE sensor exhibited excellent stability and sensitivity with a linear concentration range from 2.5 to 60 mM (R2 = 0.9903) using CV and 0.1 to 100 mM (R2 = 0.9999) using AP. The corresponding limits of detection (LOD) are 1.0 mM and 0.04 mM (S/N = 3) for CV and AP, respectively. Both linear range and sensitivity of the prepared sensor were enhanced through the combination of chalcopyrite and CB. The practicality of the proposed sensor was further tested by measuring H2O2 in real samples. Additionally, the prepared sensor showed good selectivity to H2O2, resisting interference from other potential interferent compounds (e.g., glucose, fructose, urea, catechol, and common metal ions), and the sensor possesses acceptable long-term stability. [ABSTRACT FROM AUTHOR]

Chalcopyrite and galena are primary raw materials for producing Cu and Pb metals, respectively. Flotation is still the main method to recover these two minerals. So far, lots of work has been done to recover them from low-grade refractory ores, whereas the efficient separation of these two minerals remains a major challenge. In this review, the crystal, surface, floatability and needed reagents were discussed. Firstly, the crystalline structures were introduced, including physical and chemical properties, and followed by surface properties from a density functional theory simulation perspective. As reviewed, the surface properties were closely related to their floatability, such as the degree of surface oxidization, particle size, galvanic interactions, metal ions, and so on. Moreover, the floatability of minerals could be influenced by flotation reagents, and therefore a range of new collectors and depressants were described. The review aimed to provide a deep understanding on the factors affecting Cu/Pb flotation separation as well as to develop new depressants helping to guide the flotation separation of Cu/Pb/Zn polymetallic sulfide ores for researchers. [ABSTRACT FROM AUTHOR]

Tasikmadu is a newly discovered porphyry Cu–Au prospect in the eastern Sunda arc, Indonesia. This study aimed to elucidate salient diagnostic characteristics and ore‐forming conditions of the prospect. Fieldwork and various laboratory analyses for a suite of representative samples were performed for mineralogy, bulk‐geochemistry, mineral chemistry and ore fluid characterization. The study area is composed of three diorite porphyries, that is, fine‐grained, medium‐grained and coarse‐grained diorite porphyry, respectively. The intrusions are calc‐alkaline with a high Sr/Y value, which is similar to many ore‐bearing intrusions in the eastern Sunda arc. Ore mineralization occurs in quartz veins and veinlet stockwork, centred in the potassic zone, and dominated by chalcopyrite and bornite occurring in A and B veins, which cut earlier barren (EB) and M veins. The mineralization core has an average grade of 0.63 wt% Cu and 0.25 ppm Au, respectively. Outwardly, the potassic zone changes to the propylitic zone, which still bears copper in the quartz and pyrite veinlets, although the grade is low. Fluid inclusion microthermometry revealed that the A and B veins in the potassic zone formed at 464 and 390°C by hypersaline boiling fluids, respectively. The temperature temporally and spatially decreased, that is, in the propylitic zone, the quartz veinlets formed at 260–400°C. Hypogene mineralization that formed the A veins occurred at 1.5 km below the palaeosurface, indicating a relatively shallow depth as a porphyry deposit. Nevertheless, the δ34SCDT values of sulphides range from −2.0 to −0.1‰, inferring a magmatic origin. The Tasikmadu prospect shares some similarities compared with other porphyry deposits worldwide, but it also reveals unique characteristics that differ from others, for example, potassic‐altered rocks are only typified by secondary biotite without/rare secondary K‐feldspar reflecting the lack of magma contamination by continental crustal components. In addition, current surface geological features and shallow depth erosion level of the prospect may imply that the potential of Cu–Au mineralization underneath is still open to depth. [ABSTRACT FROM AUTHOR]

Chalcopyrite selenide single crystals and epitaxial layers (CuIn1−xGaxSe2, x = 0.00, 0.08, 0.19, 1.00) were characterized by temperature‐dependent photoreflectance (PR), photoluminescence (PL), photoluminescence–excitation (PLE), and variable excitation‐energy photoluminescence (VEPL) spectroscopy. The transition energies Ea, Eb, and Ec of both CuInSe2 (CIS) and CuGaSe2 (CGS) layers sensed by PR were higher than the energies of single crystals. CuInSe2 and CuGaSe2 grown on GaAs(001) underlie compressive and tensile stresses, respectively, which lead to band‐gap broadening in CIS and band‐gap narrowing in CGS. The increase of the Ea, Eb, Ec energies of tensely stressed CuGaSe2 layers to energies higher than those of the bulk originates from the stress dependence of the non‐cubic crystal field. Band‐gap scanning of the CuGaSe2 layer with continuous‐wave Ti:sapphire‐laser confirmed the absence of correlation between band‐gap readjustment and intrinsic defects. The energy of the band‐edge exciton EFE, in the PL‐spectra, was lower than the Ea transition energy, in the PR‐spectra, which is assigned to partial quenching of ΔCF with the increase of external tensile stress by gallium‐segregation at the chalcopyrite/GaAs‐interface. The stress dependence of ΔCF is negligible in CuInSe2 and linear, with a rate of 9 meV/100 MPa, in CuGaSe2. It is revealed that the energy band‐gap of photovoltaic chalcopyrite absorbers can be tuned by simultaneous built‐in and external lattice‐tuning. [ABSTRACT FROM AUTHOR]

The concentrate grade in chalcopyrite flotation is often compromised by the associated inherently floatable gangue such as graphite. In this study, eco-friendly xanthan gum (XG) was introduced as a graphite depressant in the flotation of chalcopyrite. Single minerals flotation showed that XG strongly reduced the floatability of graphite at pH 7.5 with no significant effect on the flotation of chalcopyrite. Mixed minerals flotation showed that the addition of 20 mg/L XG increased copper grade and selectivity index by 16.83% and 14.23, respectively. This selective depressing behavior of XG was due to the strong affinity between XG and graphite as well as the weak interaction between XG and chalcopyrite, as suggested by electrokinetic and adsorption measurements. FTIR and XPS analyses indicated that the adsorption of XG on the graphite surface could be governed by physical adsorption mechanisms. Furthermore, since the contribution of hydrogen bonding interaction was insignificant, hydrophobic interaction was considered as the dominant driving force in the adsorption process. This investigation demonstrates the promising potential of XG for graphite depression and may contribute to the greening of chalcopyrite flotation process. [ABSTRACT FROM AUTHOR]

Chalcopyrite ores are processed mostly by pyrometallurgical techniques due to the refractory nature of the mineral to the current hydrometallurgical techniques. In order to overcome such refractoriness, pretreatment steps such as sulfurization may be applied to produce different copper phases and therefore improve the metal dissolution in the leaching step. The current study investigated the reaction products of the reaction between chalcopyrite and elemental sulfur at different chalcopyrite/sulfur ratios (1/1 and 1/2), reaction time (60 min and 90 min), and temperature (350ºC, 400°C and 450ºC). The sulfurization experiments revealed that covellite, nukundamite, bornite, and pyrite-like compounds were produced according to the experimental conditions applied. Then, the sulfurization products were submitted to chemical leaching tests at temperatures ranging from 32ºC to 70ºC, whereas bioleaching tests were also carried out with Acidithiobacillus ferrooxidans, at 32ºC. In the chemical leaching experiments at 70ºC, only 14% copper was recovered from the original chalcopyrite sample while the maximum copper extraction was 78% from bornite produced at 450ºC (90 min and mass ratio of chalcopyrite/sulfur of 1/2). On the other hand, copper extraction achieved 96% from the same sulfurization product containing synthetic bornite within 20 days of bioleaching. Bioleaching of the original chalcopyrite sample implied in a copper recovery of only 25% in the same period. Summarizing, the current work showed that chalcopyrite sulfurization at 450ºC was able to transform chalcopyrite into a bornite-like phase, which was chemically leached and bioleached by At. ferrooxidans. [ABSTRACT FROM AUTHOR]

Cathodoluminescence and electron backscatter diffraction have been applied to exactly the same grain boundaries (GBs) in a Cu(In,Ga)S2 solar absorber in order to investigate the influence of microstructure on the radiative recombination behaviour at the GBs. Two different types of GB with different microstructure were analysed in detail: random high angle grain boundaries (RHAGBs) and Σ3 GBs. We found that the radiative recombination at all RHAGBs was inhibited to some extent, whereas at Σ3 GBs three different observations were made: unchanged, hindered, or promoted radiative recombination. These distinct behaviours may be linked to atomic-scale grain boundary structural differences. The majority of GBs also exhibited a small spectral shift of about ±10 meV relative to the local grain interior (GI) and a few of them showed spectral shifts of up to ±40 meV. Red and blue shifts were observed with roughly equal frequency. [ABSTRACT FROM AUTHOR]

In the course of this investigation, we performed ab initio calculations. The investigation systematically explored the physical features of chalcopyrite-phase BeXAs2 (X=Sn and Ge). Total energy calculations incorporated the Wu-Cohen generalized gradient approximation (WC-GGA) [1] to consider the exchange-correlation potential. The analysis of band structures employed the modified Becke Johnson (mBJ) [2] potential approximation, renowned for its effectiveness in addressing concerns related to band gaps. The optical properties of these materials were further elucidated through the determination of the dielectric function and absorption coefficient. The analysis of electronic and optical characteristics underscores the potential applications of BeXAs2 compounds in photonics, optoelectronics, and photovoltaics. Notably, the results exhibit strong agreement with both prior theoretical investigations and experimental data. [ABSTRACT FROM AUTHOR]

Low-temperature bioleaching is relevant to the recovery of metals in alpine mines, but its development has been constrained by low bioleaching rates at high pulp concentrations. To this end, the bioleaching effect of the microbial community after the domestication of pulp concentration at 6 °C was studied. Domestication improved the bioleaching rate of copper. Environmental scanning electron microscopy (ESEM), X-ray diffraction (XRD), and electrochemical measurements revealed that the domestication process aggravated the corrosion of the chalcopyrite surface by accelerating its dissolution reaction. High-throughput sequencing technology indicated that Acidithiobacillus spp., Leptospirillum spp., and Acidiphilium spp. were the major lineages of the domesticated microbial community. The analysis of the microbial community revealed that domestication changed the microbial structure, enhancing the adaptability of the microbial community to pulp concentrations and acidic conditions. This study uncovered the mechanism by which domestication enhanced the bioleaching efficiency of the microbial community at low temperatures. [ABSTRACT FROM AUTHOR]

AgGaTe2 is an attractive material for the light‐absorbing layer in solar cells and has been deposited by close‐spaced sublimation using Ga2Te3 powder source. However, the samples exhibit an excess of Te, as well as undesired Mo–Te compounds, when AgGaTe2 is deposited on Mo/glass substrates. Therefore, the AgGaTe2 light‐absorbing layer is deposited using an Ag2Te and GaTe mixed powder source and examined herein. By replacing the Ga2Te3 source with GaTe, the Te content confirmed by the X‐ray fluorescent has significantly decreased. Cross‐sectional transmission electron microscopy observation indicates that the formation of Mo–Te compounds is suppressed. This is because Ga2Te3 produces additional Te gas in the initial decomposition reaction during deposition, and GaTe does not. In addition, the J–V curves show an improved conversion efficiency for solar cells fabricated using GaTe. [ABSTRACT FROM AUTHOR]

Copper leaching presents an environmentally friendly alternative to traditional sulfide ore processing methods. This study investigates an efficient leaching process for copper concentrate, utilizing a solution of sulfuric acid (H2SO4) and potassium iodide (KI) in a chloride medium (NaCl), enhanced by hydrogen peroxide (H2O2) at room temperature. A significant aspect of this research was optimizing the KI concentration to minimize iodide sublimation into iodine gas (I2). Through the experimental design, the optimal dosages of reagents were determined, leading to maximized copper extraction of approximately 27% in 45 min of testing at room temperature. The results showed that it is possible to obtain a suitable pregnant leach solution (PLS) (i.e., in the range of 3 to 8 g/L of Cu) for treatment in available copper solvent extraction (SX) plants with a cost of less than 4.5 USD/t Cu, according to the economic analysis carried out. The results of this study determine the most effective operational conditions for leaching and ensure a suitable PLS for SX plants in a cost-effective and environmentally friendly manner. This approach could significantly contribute to more sustainable practices in the mining and processing of copper ores. [ABSTRACT FROM AUTHOR]

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Experimental investigation of the fractionation behavior of Cu isotopes during the replacement of pyrite by Cu-bearing sulfides (chalcopyrite, bornite, and chalcocite) was conducted under hydrothermal conditions. At the initial stages of the replacement reaction, small mounds of product formed on the pyrite surface; these mounds then grew and coalesced, progressively covering the pyrite grains as the reaction proceeded. Chalcopyrite, bornite, and chalcocite formed sequential monomineralic zones from the pyrite reaction front towards the solution. During the early stage of the reaction, Cu isotope fractionation between the solids and the aqueous solution (Δ65Cu solid-aqueous , Δ65Cu solid-aqueous = δ65Cu solid – δ65Cu aqueous) was approximately –0.6 ‰, similar to the calculated equilibrium Cu isotope fractionation factors between Cu-bearing sulfides (chalcopyrite, bornite, and chalcocite) and CuCl 2 –. However, the Δ65Cu solid-aqueous moved progressively further from equilibrium with prolonged reaction time, with fractionation factors ranging from approximately –0.6 ‰ to –1.2 ‰. We found that significant fractionation of Cu isotopes between the solid products and aqueous solution was mainly controlled by the amount of chalcopyrite that formed in the product layers. We interpret that the Δ65Cu solid-aqueous was controlled by the diffusion of aqueous Cu(I) species among the product layers and the changes in Cu redox state during the precipitation of chalcopyrite. These results imply that the δ65Cu values measured in sulfides from low-temperature hydrothermal deposits may be controlled by the local chemistry of the fluids in product layers that precipitate sulfides. This study highlights the importance of local fluid characteristics, such as redox conditions, metal speciation, and diffusion, in controlling isotope fractionation pathways during non-equilibrium mineral replacement. [ABSTRACT FROM AUTHOR]

Although the flotation separation of sulfides and their electrochemical interactions have been examined in some investigations, study the direct relationship between the flotation kinetics of sulfides and their galvanic interactions during the process yet has not been addressed. To fill this gap, an extensive study was conducted to explore the effect of galvanic interactions for chalcopyrite and pyrite on their flotation kinetics when they are wetting ground by three different grinding media types (steel, chromium, and ceramic). Assessment of the flotation test results indicated that there was no galvanic interaction between the ceramic grinding balls and chalcopyrite. The galvanic interactions were mostly related to the grinding of chalcopyrite by steel balls. EDTA analysis showed that by increasing the amount of iron oxy/hydroxy and their precipitations on the surface of chalcopyrite, the recovery of chalcopyrite was decreased. Furthermore, increasing the pyrite content in the flotation of chalcopyrite increased the flotation rate constant and then decreased it. Flotation tests demonstrated that grinding chalcopyrite by ceramic media type, which has lower electrochemical activity in comparison with the other considered media, can be resulted in a higher flotation rate constant and ultimate recovery. Grinding the mixture of chalcopyrite and pyrite by steel or chromium media can show almost the same effect on the flotation rate constant and ultimate recovery. In general, the experimental results showed that by increasing the galvanic interaction, the flotation recovery and flotation kinetics were decreased.

This is an article in the field of mineral processing engineering. The comprehensive recovery test of silver, gold and copper bearing sulfide concentrate was carried out. With isobutyl xanthate and sodium diethyl dithiocarbamate as a combined collector, calcium oxide as the depressant, 2# oil as a frother, which produced a concentrate approaching 16.66% Cu grade at 86.96% recovery, Au content of 278.95 g/t at 75.56% Au recovery and Ag content of 1848.74 g/t at 78.55% Ag recovery by a flotation process consisting of one stage of roughing，three stages of cleaning and two stages of scavenging was used to collect lead minerals. The comprehensive recovery of copper from sulfur concentrate has been effectively realized. At the same time, gold and silver are well enriched in copper concentrate, which is convenient for recovery and utilization, and the mineral processing index is ideal.

Sodium dithionite (Na2S2O4) is a widely used reducing agent to control pulp potential (Eh) and pyrite depressant in sulfide ore flotation. In this study, the pyrite depressant effect of sodium dithionite on gold ore flotation was investigated at pH 8 and pH 10.5 comparatively in terms of gold, chalcopyrite, and pyrite recoveries and grades. The presence of sodium dithionite resulted in a drop of approximately 50–70 mV in the Eh values, regardless of the studied pH values, confirming the reducing effect of sodium dithionite. The effects of sodium dithionite on gold and chalcopyrite grades and recoveries were quite limited, especially at pH 10.5. At pH 8, the utilization of sodium dithionite slightly decreased gold and chalcopyrite recovery and grades, while the decrease in pyrite recovery and grades was remarkable. Both pyrite recovery and grade were reduced from 79.5% to 54.7% and 15.3% to 10.7% by the utilization of sodium dithionite at pH 8. In conclusion, it is considered that the selective flotation of gold and chalcopyrite from pyrite can be achieved at a lower pH accompanied by a slightly reduced Eh by the utilization of sodium dithionite.

\nKEY FINDINGSThe demand for copper drives hydrometallurgical innovation amidst high-grade resource depletion. Compared to pyrometallurgy, biohydrometallurgy presents eco-friendly, cost-effective solutions for ore processing. Semiconductor minerals, notably chalcopyrite, which corresponds to the largest source of copper in the earth’s crust, play a critical role. However, chalcopyrite electrochemical behavior in bioleaching remains underexplored. Therefore, this review emphasizes the exploration of irradiation’s influence on biohydrometallurgy, particularly through the utilization of photoreactions or mineral photo corrosion. The focus is on examining the semiconductor properties of chalcopyrite to incorporate it into biohydrometallurgical frameworks and to develop models elucidating the impact of light on the bioleaching of chalcopyrite.Chalcopyrite leaching is governed by semiconductive properties rather than passive layer formation.The transport of charge carriers across the space charge region may be the rate-limiting step in hydrometallurgical processes.High solution potentials lead to charge carrier depletion and reduced reaction kinetics in the dark.Electron injection into Fe3d S3p antibonding orbitals at low solution potentials increases charge carrier concentration, enhancing reduction and intermediate formation.Light irradiation boosts reaction rates by exciting electrons, facilitating their capture by Fe3+ ions, aiding bioleaching, and injecting electrons into the photo-generated holes.Chalcopyrite leaching is governed by semiconductive properties rather than passive layer formation.The transport of charge carriers across the space charge region may be the rate-limiting step in hydrometallurgical processes.High solution potentials lead to charge carrier depletion and reduced reaction kinetics in the dark.Electron injection into Fe3d S3p antibonding orbitals at low solution potentials increases charge carrier concentration, enhancing reduction and intermediate formation.Light irradiation boosts reaction rates by exciting electrons, facilitating their capture by Fe3+ ions, aiding bioleaching, and injecting electrons into the photo-generated holes.Suggestions for future research in the area of biohydrometallurgy: Investigate conditions favoring the accumulation of majority charge carriers on the chalcopyrite surface.Explore light irradiation with sufficient energy to excite electrons from the valence band to the empty orbitals between the valence and conduction bands and the conduction band itself, using different wavelengths.Study the combined effects of light and iron-oxidizing microorganisms on chalcopyrite bioleaching.Therefore, understanding and applying the semiconductor nature of chalcopyrite is crucial for improving hydrometallurgical processes and enhancing copper recovery efficiency through photo-biohydrometallurgy.Investigate conditions favoring the accumulation of majority charge carriers on the chalcopyrite surface.Explore light irradiation with sufficient energy to excite electrons from the valence band to the empty orbitals between the valence and conduction bands and the conduction band itself, using different wavelengths.Study the combined effects of light and iron-oxidizing microorganisms on chalcopyrite bioleaching.Therefore, understanding and applying the semiconductor nature of chalcopyrite is crucial for improving hydrometallurgical processes and enhancing copper recovery efficiency through photo-biohydrometallurgy. [ABSTRACT FROM AUTHOR]

Aluminum‐based chalcopyrite materials have attracted attention because of the wide controllability range of their material properties and potential for use in energy‐conversion devices. Herein, CuAlSe2‐based thin‐film growth and solar cell device properties are discussed. Ternary CuAlSe2 thin films are relatively unstable and decompose weeks after film growth, even when preserved in a dry box. However, alloying with elemental In led to significant improvements in stability. Cu(In,Al)Se2 (CIAS) solar cells yield better photovoltaic performance than CuInSe2 cells, although the effective range of Al concentration that can improve device performance is narrower than that of elemental Ga in Cu(In,Ga)Se2 (CIGS). A decrease in the alkali metal concentration in CIAS films with increasing Al concentration is observed, indicating that the formation energy of alkali‐metal substitutional defects on the Cu site is high, and/or Al‐related complex defects formed are kinetically stable and difficult to replace with alkali metals once they form. Although the direct observation of alkali metals in the bulk (grain interior) of chalcopyrite CuInSe2 and CIGS films has been difficult to date, this result can serve as indirect evidence of the presence of alkali metals in the bulk of CuInSe2 films. [ABSTRACT FROM AUTHOR]

High‐efficiency Cu(In,Ga)Se2 solar cells rely on Ga grading to mitigate back surface recombination. However, the inhomogeneous absorber has drawbacks, including increased non‐radiative loss and inadequate absorption. Therefore, literatures demand a paradigm shift of using a hole‐transport layer to passivate the back surface. Herein, a functional hole‐transport layer is demonstrated as an alternative to Ga grading. The novel hole‐transport layer is prepared as a double‐layer: co‐evaporated CuGaSe2 covered by solution combustion synthesis prepared In2O3. As demonstrated by micrographs, elemental mapping, and photoluminescence spectroscopy, the oxide layer improves thermal stability and prevents Ga diffusion. However, during the absorber deposition, a complete ion exchange of In and Ga converts CuGaSe2/In2O3 into CuInSe2/GaOx. Incorporating this hole‐transport layer in co‐evaporated nongraded CuInSe2 solar cells leads to significantly increased minority carrier lifetime from 5 to 113 ns, yielding an 80 meV improvement in quasi‐Fermi‐level splitting. The devices exhibit improved open‐circuit voltage, as well as a promising fill factor of over 71%, indicating good hole‐transport properties. In these results, the passivation effect and good hole‐transport properties of the hole‐transport layer are experimentally demonstrated. Thus, high‐efficiency solar cells can be achieved by using a functional hole‐transport layer without relying on Ga grading. [ABSTRACT FROM AUTHOR]

The demand for non-ferrous copper metals has increased dramatically with the development of the global economy; accordingly, some refractory copper sulfide ores with low grade and their associated minerals are beginning to be utilized, making the flotation separation of copper concentrates exceptionally difficult, especially the separation of chalcopyrite and pyrite. In this paper, S-allyl-O, O′-dibutyl phosphorodithioate (ADTP) was synthesized by a one-pot method and used as a chalcopyrite collector in the flotation separation of chalcopyrite and pyrite. Flotation experiments results have shown that ADTP exhibits better selectivity and greater collecting power for chalcopyrite under neutral or weak base conditions. The 95% recovery of chalcopyrite can be achieved at pH 8.0 and 8.0 mg/L ADTP. From the analysis results of the contact angle, the SEM-EDS spectrogram, and elemental mapping, it was found that ADTP adsorbed uniformly on a chalcopyrite surface and made a significant contribution to the hydrophobicity of the surface. Confirmed by FTIR and XPS analysis, ADTP was able to form P–S–Cu bonds on a chalcopyrite surface, proving that it was adsorbed on the chalcopyrite surface in the form of chemisorption. [ABSTRACT FROM AUTHOR]

In order to substantiate the possibility of obtaining glass–ceramics from glasses based on slags from the joint smelting of silicate nickel and copper pyrite ores, the crystallization ability of model samples (particle size < 0.1 mm) that are close in composition and structure to real prototypes was evaluated. Using the methods of differential scanning calorimetry (5–20 °C·min−1 heating rate) and X-ray powder diffraction, it was established that in an inert atmosphere, crystallization is accompanied by the formation of products, the crystalline part (46.6–71.6 mass%) of which is represented by associations of pyroxenes and anorthite. The primary crystallizing phase is pyroxene. The transition from iron-free to iron-containing sample leads to a change in the composition of pyroxene from enstatite to pigeonite, a shift in the range of formation of these associations from 826–1018 to 728–874 °C, and additional (966–1068 °C) formation of silica. Kinetic analysis (Ozawa–Flynn–Wall and multi-variate nonlinear regression methods) showed consecutive bulk nucleation of pyroxenes and anorthite with the formation of two- and one-dimensional nuclei by a chain mechanism, passing into diffusion-controlled two- and three-dimensional crystal growth. The activation energy of enstatite nucleation (671 kJ·mol−1) is significantly higher than for pigeonite (418 kJ·mol−1), and for crystal growth (444 and 534 kJ·mol−1, respectively), the reverse relationship is noted. Pyroxenes promote the heterogeneous nucleation of anorthite. The activation threshold for the release of the latter in an iron-free sample (220 kJ·mol−1) is three times higher than in an iron-containing one (76 kJ·mol−1). The formation of two- and one-dimensional silica nuclei in the bulk of glass is synchronized with their two-dimensional growth under conditions of diffusion deceleration. The results obtained can be used in the development of technologies for producing glass–ceramics from various types of technogenic and mineral raw materials. [ABSTRACT FROM AUTHOR]

The adsorption of a conductive mineral toward a collector changes its interface electrochemical property, implying the hydrophobization mechanism of froth flotation. Herein, the interface electrical behavior of chalcopyrite was investigated by in situ scanning electrochemical microscopy (SECM). And the results demonstrated that the treatment of N, N-diethyl-S-[2-amino-2-(hydroxyimino) ethyl] dithiocarbamate ester (DEAHEDTC) significantly reduced the tip feedback current i and heterogenous electron transfer rate constant k of chalcopyrite interface, implying the self-assembly of DEAHEDTC on chalcopyrite surface. The adsorption mechanism investigations further revealed that both DEAHEDTC's C(=NOH)-NH2 and N-C(=S) groups combined with the surface Cu atom(s) of chalcopyrite, leaving its hydrophobic groups outward against chalcopyrite. For the hydrophobic groups that are non-conducting, the electrochemical activity of chalcopyrite interface decreased. While the hydrophobization of DEAHEDTC returned a high flotation recovery of chalcopyrite particles. [ABSTRACT FROM AUTHOR]

The oxidative flotation separation of chalcopyrite from pyrite in weak alkaline seawater solution was investigated using potassium ferrate (K2FeO4) as the oxidizing reagent. The optimal K2FeO4 concentration of 0.25 kg/t was found to strongly depress pyrite (from 88.05% to 7.92%) but insignificantly influence chalcopyrite (remaining at around 93%). K2FeO4 oxidized pyrite to form hydrophilic Fe2O3, Fe(OH)3, FeOOH, and Fe2(SO4)3 that covering on pyrite surface to prevent the adsorption of collector sodium butyl xanthate (SBX), thereby depressing pyrite flotation. Although a small amount of hydrophilic species was formed on chalcopyrite surface after the addition of K2FeO4, some hydrophobic substances such as S22-/Sn2-/S0 were also observed, resulting in an unaffected overall floatability. Further, density functional theory (DFT) calculation proved that the activity of Fe on chalcopyrite surface was much lower than that on pyrite. Therefore, this study provides a green way to separate chalcopyrite from pyrite effectively in a low-alkali seawater system, which is of significance to the separation of sulfide minerals in the fresh water-lack areas. [ABSTRACT FROM AUTHOR]

This paper review presents a comparison between conventional leaching and advanced photochemical leaching processes and their potential for use in chalcopyrite leaching. Likewise, it presents an analysis of the differences between the advanced leaching processes, photoleaching and radical-leaching, indicating that the photochemical mechanisms (photooxidation/photoreduction and generation of radical oxygen species (ROS) and radical sulfur species (RSS)) would improve the oxidative dissolution of chalcopyrite, taking advantage of the high oxidizing power of free radicals. Initial experimental results of solar-assisted radical-leaching on chalcopyrite are presented, demonstrating that sulfate radicals (SO4−) allow copper to be leached at a rate 4.7 times higher than in the absence of radicals and sunlight. With these results, a radical-leaching process is presented for the first time, with a perspective toward the future development of a new hydrometallurgical route: solar-assisted radical-leaching. [ABSTRACT FROM AUTHOR]

The effect of adding orders of inorganic regulators such as zinc sulfate, copper sulfate, sodium sulfite and sodium sulfide on the flotation of chalcopyrite, galena, and sphalerite was studied under the Z-200 collector system. The results of microflotation tests showed that compared with adding inorganic regulator before the Z-200, when the inorganic regulator was added after the Z-200, there were differences in the effect on the flotation of the three kinds of sulfide minerals: the depressing effect of zinc sulfate on chalcopyrite, especially galena, was significantly weakened, and the depressing effect of zinc sulfate on sphalerite was weakened at lower dosage, but stronger at higher dosage. Copper sulfate slightly enhanced the depressing effect on chalcopyrite, had a strong activation effect on galena, especially at lower dosage, the activation effect of copper sulfate on sphalerite was significantly enhanced at lower dosage, and was weakened at higher dosage. Sodium sulfite weakened its depressing effect on chalcopyrite, especially galena, and enhanced the depressing effect on sphalerite. Sodium sulfide weakened its depressing effect on chalcopyrite, had a similar activation effect on galena at lower dosage, while its depressing effect was enhanced at higher dosage, and enhanced its depressing effect on sphalerite at low dosage. The research results can provide reference for the selection and the adding sequence of inorganic regulators in the flotation separation of sulfide ores under the Z-200 collector system. [ABSTRACT FROM AUTHOR]

In nature, arsenopyrite commonly acts as a companion mineral of chalcopyrite. As the arsenic in arsenopyrite easily exudes during the smelting process, arsenic will not only pollute the environment but also seriously affect human health once it flows into the nature, so it is important to realize the separation of arsenopyrite and chalcopyrite. Flotation is the most efficient and commonly used means to separate these two minerals. As the floatability of arsenopyrite is similar to that of chalcopyrite, the two are usually separated using depressants to suppress arsenic and float copper. The commonly used inorganic depressants in the separation process of copper and arsenic have drawbacks such as poor selectivity, strong toxicity, and environmental pollution. Therefore, the development of a clean, efficient and non-toxic inhibitor is the key to the separation of copper and arsenic. Ethylenediamine tetramethylene phosphoric acid (EDTMP) was developed as a novel depressant of arsenopyrite to achieve the separation of arsenopyrite and chalcopyrite. Micro-flotation experiments and artificial mixture flotation tests verified the flotation performance of EDTMP, and the mechanisms of EDTMP adsorbed on arsenopyrite and chalcopyrite surface were revealed by Zeta potential, FTIR spectrum, and XPS measurements. The flotation experiments revealed that EDTMP could effectively depress the flotation of arsenopyrite without affecting chalcopyrite at pH = 10 and SIBX concentration of 200 mg/L, and the results of zeta potential and FTIR spectrum indicated that EDTMP is preferred to adsorb on arsenopyrite, which hindered the adsorption between SIBX and arsenopyrite. XPS results showed that EDTMP chemisorbed on arsenopyrite surface in the form of P-O-Fe bonds, while EDTMP weakly physisorbed on chalcopyrite surface. EDTMP was a novel arsenopyrite depressant, which was highly efficient, clean, and environmentally friendly compared to traditional depressants. [ABSTRACT FROM AUTHOR]

In order to fully understand the properties of a certain copper ore and develop a reasonable beneficiation process, a comprehensive analysis was conducted using chemical multi-element analysis, optical microscopy, MLA, and other methods to analyze the chemical composition, mineral types, structural characteristics, embedded features of the main minerals, and occurrence status of the main useful elements in the ore. It was found that the main useful elements in the ore were Cu and S, with grades of 1.73% and 20.81% respectively, as well as associated precious metal elements Au and Ag, with grades of 0.63 g/t and 5.46 g/t respectively. The main copper minerals were chalcopyrite, followed by tennatite and tetrahedrite, and the grain sizes of the copper minerals were above 0.020 mm and below 0.147 mm, mainly embedded in sulfide and vein minerals. The metal sulfides were mainly pyrite, with particle sizes mainly above 0.043 mm and below 0.417 mm, requiring fine grinding for individual dissociation during beneficiation. The gold minerals were mainly native gold and electrum, mainly in the form of fine particles, embedded in sulfide and vein minerals with a complex intergrown relationship and a relatively high difficulty in recovery. The distribution of silver elements was relatively scattered, most distributed in pyrite and copper minerals. Based on these results, it is recommended to use the "copper -- sulfur bulk flotation -- copper--sulfur separation flotation process" to process the copper ore, and to separate the bulk copper -- sulfur concentrate after re-grinding. Gold and silver can be recovered respectively in copper concentrate, sulfur concentrate, and tailings. [ABSTRACT FROM AUTHOR]

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Ag-Pb-Cu mixed concentrate is a product ofcopper and lead floating and contains a silver grade of 4208.0 g/t, along with 3.3% of copper and 43.28% of lead. And 98.80% of silver is deposited in galena. The surface of the concentrate has been heavily contaminated with the flotation reagents, leading to a little difference in the floatability between galena and chalcopyrite. Consequently, separating chalcopyrite from galena is very difficult. In this experimental study, a combined process of removing the flotation reagents by activated carbon and flotating copper by the suppression of lead was adopted to treat the concentrate. By using a high-efficiency galena inhibitor (GYC) and chalcopyrite collector (SAC), an effective recovery of silver, lead and copper from the mixed concentrates was achieved. After the treatment of the mixed concentrate, the silver grade in obtained silver-lead concentrate was 4839.2 g/t with a recovery rate of 97.36% and the grade of lead was 50.05% with a recovery rate is 97.90%. In obtained copper concentrate, the silver grade was 724.6 g/t with a recovery rate of 2.64% and the copper grade was 20.16% with a recovery rate of 91.23%. [ABSTRACT FROM AUTHOR]

Chalcopyrite ore is one of the most abundant and pertinent oxidized copper minerals. In this research, the dissolution kinetics of chalcopyrite in an ammonia solution was examined. During leaching, the influences of leachant concentration, temperature, and particle diameter on the extent of copper ore dissolution were investigated. However, it was affirmed that the dissolution efficiency of chalcopyrite ore increased with decreasing particle fraction and increasing reaction temperature and ammonia concentration. About 68.6% copper ore dissolution was achieved with 2.0 mol/L NH3, 75 ºC reaction temperature, and 45 μm particle diameter within 120 minutes. The dissolution reaction mechanism was found to be described by diffusion-control with a calculated activation energy of 32.26 kJ/mol. In the XRD spectra of the residual product obtained at established conditions, CuFeS2 peaks were absent, indicating the leachability of the sample. Hence, the leach residue could serve as an important by-product for some local industries. [ABSTRACT FROM AUTHOR]

We present an investigation into the magnetism exhibited by AMY2 compounds characterized by a chalcopyrite structure, where A can be Cu or Ag, M can be Sc, Ti, V, Cr, Mn, or Fe, and Y can be either S or Se. By substituting M atoms at the Ga position of AGaY2 compounds, the magnetic properties were calculated using the full potential linearized augmented plane wave method under the generalized gradient approximation and local spin density approximation with the WIEN2K code. The obtained spin-polarized results confirmed the presence of ferromagnetic and half-metallic (HM) properties in AMY2 compounds (A = Cu, Ag; M = Ti, V, Cr, Mn; Y = S, Se), wherein the HM property is preserved through p-d hybridization of p states of Y (S, Se) atoms with d (t2g) states of M (M = Ti, V, Cr, Mn) atoms, and minimal contribution of −s states of A (A = Cu, Ag) atoms. The total magnetic moments for AMY2 compounds were calculated as 1.00, 2.00, 3.00, and 4.00 µB/f.u. for M = Ti, V, Cr, Mn, respectively. For AFeY2 compounds (A = Cu, Ag; Y = S, Se), electronic band structures for both up spin and down spin states were identical, suggesting antiferromagnetic behavior at equilibrium, while AScY2 compounds (A = Cu, Ag; Y = S, Se) exhibited nonmagnetic properties at equilibrium. Overall, the accurate HM properties of AMY2 materials suggest promising prospects for their utilization in spintronics and magnetic storage device applications. [ABSTRACT FROM AUTHOR]

The article presents the synthesis and application of a novel collector, 5-methyl butylxanthate-1,2,4-triazole-3-thione (MBuXTT), for chalcopyrite flotation separation from pyrite. Various interfaces and surface characterization analysis methods were employed to study the flotation separation mechanism. The micro-flotation and contact angle experiments demonstrated a significant enhancement in the surface hydrophobicity of chalcopyrite following treatment with MBuXTT. Within the pH range investigated, MBuXTT effectively enriched chalcopyrite while separating it from pyrite. Compared to the traditional collector sodium butyl xanthate, MBuXTT exhibited superior selectivity and collecting ability towards chalcopyrite. Adsorption of MBuXTT on the chalcopyrite surface was found to be an endothermic-spontaneous chemisorption process. ζ-Potential analyses and UV spectra confirmed specific adsorption of MBuXTT on chalcopyrite rather than pyrite surfaces. Additionally, FTIR, XPS, and DFT calculations were conducted to explore the adsorption mechanism on the chalcopyrite surface, and the results indicated that MBuXTT-Cu complexes can be covered on the chalcopyrite surface with formation of Cu(I)-S and Cu(I)-N bonds along with release of H+ and oxidation product formation involving S–S bonds. [ABSTRACT FROM AUTHOR]

The Shuangjianzishan silver polymetallic deposit is located in the copper–tin–lead–zinc–silver polymetallic metallogenic belt in the Southern Great Xing'an Range, with silver resources of more than 18,000 t, which is the largest silver polymetallic deposit in Asia. Early studies concluded that the Shuangjianzishan deposit is typically an epithermal Ag-Pb-Zn deposit that lacks a high-temperature mineralization stage. In recent years, with the deepening of research, a large amount of Cu-Sn mineralization has been found in the deep part of the Shuangjianzishan deposit, but it is less studied. The laser-ablation inductively coupled mass spectroscopy (LA-ICP-MS) technique is used to investigate the distribution and substitution of trace elements in chalcopyrite and cassiterite. In this paper, the trace element study of chalcopyrite and cassiterite from the Shuangjianzishan deposit reveals that Sn, In, As, Se, Sb, and Tl mainly exist in chalcopyrite in isomorphic form, while Pb, Bi, and Ni mainly exist in chalcopyrite in the form of mineral inclusions. The enrichment of the high-temperature elements Sn and Se in chalcopyrite, and the deficit of the middle- and low-temperature elements Ga, Sb, etc., reflect that the chalcopyrite in the Shuangjianzishan deposit was formed in a middle- and high-temperature environment, and it also indicates that the early ore-forming hydrothermal solution may be rich in Sn. Fe, In, Co, and Ni mainly exist in cassiterite in isomorphic form, and the content of W in cassiterite is high. There are two main forms, one is isomorphic and the other is wolframite inclusion. Cassiterite has Fe-rich and W-U-poor characteristics, indicating that cassiterite from the Shuangjianzishan deposit was formed under relatively oxidized conditions, and the relative enrichment of elements such as Fe, W, Zr, and Hf indicates that the temperature of cassiterite formation was high. The elemental content and inter-ionic coupling relationships suggest that the cassiterite from the Shuangjianzishan deposit may have an elemental replacement mechanism of W6+ + Fe2+ ↔ 2Sn4+ or Fe3+ + OH− ↔ Sn4+ + O2−. The trace elements in cassiterite of the Shuangjianzishan deposit are rich in Fe and Mn and depleted in Nb and Ta, according to the Fe-W diagram, and the tin mineralization of the Shuangjianzishan deposit belongs to cassiterite–sulfide-type tin mineralization. Chalcopyrite Co/Ni ratios >1 are consistent with the characteristics of chalcopyrite genesis in hydrothermal deposits. [ABSTRACT FROM AUTHOR]

Designing effective strategies for mitigating energy crisis highlights a research gap in current solar cell technologies. This study explores the inherent physicochemical properties of thin films composed of copper gallium sulfide telluride (CuGa1−xCrx(S,Te)2) with chromium substitution, prepared through the chemical spray pyrolysis technique. The investigation showcases how the concept of intermediate band structuring contributes to enhancing solar cell efficiency. This enhancement can be attributed to the remarkable mobility (from 1.80 to 5.48 cm2 V−1 s−1) and conductivity (from 1.00 to 6.06 S cm−1) exhibited by pure and 0.1 chromium thin films, respectively. Notably, the Cr‐0.1‐substituted CGST film displays maximum photoresponsivity of 0.624 AW−1, an external quantum efficiency of 145%, and a detectivity of 2.37E10. The fabricated solar cell is subjected to theoretical simulation using solar cell capacitance simulator‐1D software, revealing an upward trend in efficiency from 7.13% to 11.23% with increasing Cr substitution from 0.025 to 0.1. This efficiency improvement can be ascribed to the reduction in bandgap (from 2.40 to 1.72 eV) and the creation of a sub‐band in CGST due to Cr incorporation, as substantiated by UV–vis and NIR spectroscopy. These outcomes suggest that Cr‐0.1‐substituted CGST holds promise as a potential thin film absorber material in solar photovoltaics. [ABSTRACT FROM AUTHOR]

This work focuses on the synthesis and properties of quaternary ZnSnP2-yAsy chalcopyrite solid solutions. Full miscibility of the solid solution is achieved using ball milling followed by hot press sintering. The measured electrical conductivity increases substantially with As substitution from 0.03 S cm−1 for ZnSnP2 to 10.3 S cm−1 for ZnSnAs2 at 715 K. Band gaps calculated from the activation energies show a steady decrease with increasing As concentration from 1.4 eV for ZnSnP2 to 0.7 eV for ZnSnAs2. The Seebeck coefficient decreases significantly with As substitution from nearly 1000 μV K−1 for ZnSnP2 to −100 μV K−1 for ZnSnAs2 at 650 K. Thermal conductivity is decreased for the solid solutions due to alloy phonon scattering, compared to the end members with y = 0 and y = 2, with the y = 0.5 and y = 1.0 samples exhibiting the lowest values of 1.4 W m−1 K−1 at 825 K. Figure of merit values are increased for the undoped solid solutions at lower temperatures when compared to the end members due to the decreased thermal conductivity, with the y = 0.5 sample reaching zT = 1.6 × 10−3 and y = 1 reaching 2.1 × 10−3 at 700 K. The largest values of the figure of merit zT for the undoped series was found for y = 2 with zT = 2.8 × 10−3 at 700 K due to the increasing n-type Seebeck coefficient. Boltztrap calculations reveal that p-doping could yield zT values above unity at 800 K in case of ZnSnAs2, comparable with ZnSnP2. [ABSTRACT FROM AUTHOR]

The presented main studies of point defects in CdGa2Se4 chalcopyrite are considered to quantify the formation energies of three possible models of Cd, Ga and Se vacancy defects using various local density approximation (LDA) and general gradient approximation (GGA) approximations. Using supercells with 56 atoms, interatomic distances were calculated both for an ideal cell and a supercell containing vacancies. It was found that interatomic distance does not change only in a supercell containing Ga vacancy. Investigation shows that the Ga vacancy has a high defect formation energy (DFE) among other intrinsic vacancies and is therefore unstable. We found that for all vacancies, − 2 charge states are favorable. [ABSTRACT FROM AUTHOR]

The presented main studies of point defects in CdGa2Se4 chalcopyrite are considered to quantify the formation energies of three possible models of Cd, Ga and Se vacancy defects using various local density approximation (LDA) and general gradient approximation (GGA) approximations. Using supercells with 56 atoms, interatomic distances were calculated both for an ideal cell and a supercell containing vacancies. It was found that interatomic distance does not change only in a supercell containing Ga vacancy. Investigation shows that the Ga vacancy has a high defect formation energy (DFE) among other intrinsic vacancies and is therefore unstable. We found that for all vacancies, − 2 charge states are favorable. [ABSTRACT FROM AUTHOR]

The paper presents theoretical investigations of the elastic and acoustic properties in crystals forming the solid solution system CuGa(S1 − xSex)2 . The structures with varying selenium content, x = 0, 0.25, 0.5, 0.75, and 1, were examined. Employing the supercell method, a series of solid solutions were modeled by replacing sulfur atoms with selenium atoms in the CuGaS2 crystal structure. The generated substitution structures underwent geometry optimization using density functional theory (DFT) in conjunction with the BFGS algorithm, describing the exchange-correlation interactions through generalized gradient approximation (GGA). The optimized structures of the solid solutions were found to be in good agreement with the available experimental data, with a slight overestimation of parameters, attributed to the known features of the GGA functional. The elastic constants matrix Cij for tetragonal symmetry was calculated, demonstrating compliance with Born's mechanical stability criterion for all compositions investigated. The evaluation of the material's elastic characteristics with changing composition revealed that the coefficients and C33 exhibited nearly twice as large values compared to the shear coefficients. Notably, the C11 coefficient reached 104.79 GPa, while the minimum value was obtained for C44 at 51.29 GPa. Isomorphic replacement of sulfur with selenium atoms resulted in a monotonic decrease in the elastic constants Cij. Employing the Green-Christoffel equation, the acoustic wave propagation velocities in a number of crystals were calculated using a home-made program written in Python. Acoustic wave velocities v were computed in (100) and (001) planes, with the highest observed velocity v max = 5586 m/s corresponding to the longitudinal acoustic wave (LA) in the (001) plane. The isomorphic replacement of S → Se resulted in a monotonic reduction in the propagation velocity v of acoustic waves within the investigated solid solution system. An analysis of anisotropy revealed that transverse TA2 waves exhibited the highest values for the A coefficient, accounting for 35-43% in the (100) plane and 28-40% in the (001) plane. In contrast, for LA waves, the propagation velocity was nearly isotropic (A parameter close to zero). [ABSTRACT FROM AUTHOR]

In the flotation separation process of a Cu-Mo-W polymetallic ore, the wastewater from the scheelite cleaning flowsheet contains large numbers of residual flocculants and metal ions, and the separation of chalcopyrite and molybdenite requires a large number of environmentally harmful depressants. Therefore, it is necessary to find new methods to reduce the environmental and cost pressures of wastewater treatment and the use of depressants. In this work, the flotation wastewater from the scheelite cleaning flowsheet for the separation of chalcopyrite and molybdenite by selective surface passivation was investigated for the first time. Flotations of single minerals and artificially mixed minerals with or without immersion pretreatment in the presence and absence of aeration were performed. The results showed that pulp pH had no effect on the flotation of either mineral, and a molybdenite recovery of 93.22% with a chalcopyrite recovery of 10.77% was achieved under the conditions of 10 days of immersion pretreatment with aeration, 350 mg/L of kerosene, and 100 mg/L of MIBC. By combining the electrochemical cyclic voltammetry analysis and characterization by XRD and SEM, the selective surface passivation mechanism of chalcopyrite was discussed, which could be due to the coverage of the insoluble oxidation products, especially jarosite. This work has simultaneously achieved the depressant-free flotation separation of molybdenite and chalcopyrite and the reuse of scheelite flotation wastewater, which is of great significance for environmental protection and cost saving. [ABSTRACT FROM AUTHOR]

The paper presents theoretical investigations of the elastic and acoustic properties in crystals forming the solid solution system CuGa(S1 − xSex)2 . The structures with varying selenium content, x = 0, 0.25, 0.5, 0.75, and 1, were examined. Employing the supercell method, a series of solid solutions were modeled by replacing sulfur atoms with selenium atoms in the CuGaS2 crystal structure. The generated substitution structures underwent geometry optimization using density functional theory (DFT) in conjunction with the BFGS algorithm, describing the exchange-correlation interactions through generalized gradient approximation (GGA). The optimized structures of the solid solutions were found to be in good agreement with the available experimental data, with a slight overestimation of parameters, attributed to the known features of the GGA functional. The elastic constants matrix Cij for tetragonal symmetry was calculated, demonstrating compliance with Born's mechanical stability criterion for all compositions investigated. The evaluation of the material's elastic characteristics with changing composition revealed that the coefficients and C33 exhibited nearly twice as large values compared to the shear coefficients. Notably, the C11 coefficient reached 104.79 GPa, while the minimum value was obtained for C44 at 51.29 GPa. Isomorphic replacement of sulfur with selenium atoms resulted in a monotonic decrease in the elastic constants Cij. Employing the Green-Christoffel equation, the acoustic wave propagation velocities in a number of crystals were calculated using a home-made program written in Python. Acoustic wave velocities v were computed in (100) and (001) planes, with the highest observed velocity v max = 5586 m/s corresponding to the longitudinal acoustic wave (LA) in the (001) plane. The isomorphic replacement of S → Se resulted in a monotonic reduction in the propagation velocity v of acoustic waves within the investigated solid solution system. An analysis of anisotropy revealed that transverse TA2 waves exhibited the highest values for the A coefficient, accounting for 35-43% in the (100) plane and 28-40% in the (001) plane. In contrast, for LA waves, the propagation velocity was nearly isotropic (A parameter close to zero). [ABSTRACT FROM AUTHOR]

This is an article in the field of mineral processing engineering. Chalcopyrite, galena and sphalerite are usually associated with each other. In order to find out the influence of Pb2+ and Zn2+ on the flotation behavior and surface characteristics of chalcopyrite, the difference of the influence of Pb2+ and Zn2+ on the floatability of chalcopyrite was studied by single mineral flotation test, solution chemical calculation, Zeta potential and XPS detection. The results show that Pb2+ and Zn2+ are adsorbed on the surface of chalcopyrite, which changes the Zeta potential of chalcopyrite surface and inhibits the floatability of chalcopyrite, and the inhibition increases with the increase of pH value. According to the flotation test results, zinc is mainly adsorbed on the surface of chalcopyrite in the form of Zn(OH)2 precipitation in the range of pulp pH, which has an inhibitory effect on the flotation of chalcopyrite. Therefore, the inhibitory effect of Zn2+ on the flotation of chalcopyrite is more significant than that of Pb2+ and XPS results show that Pb2+ and Zn2+ can precipitate on the surface of chalcopyrite and exist on the surface of chalcopyrite in the form of chemical adsorption, thus inhibiting the floatability of chalcopyrite.

A novel chalcopyrite functionalized catalytic ceramic membrane was developed and exhibited superior dual properties for micropollutants removal and membrane fouling control. [Display omitted] • A new catalytic ceramic membrane coated with chalcopyrite was developed. • Pollutant removal was more efficient in the confined membrane pore structure. • SO 4 •− mediated radical pathway played dominant role for pollutant removal. • The repulsive interaction between foulants and the membrane was enhanced. • Standard blocking was the main fouling pattern in the oxidation-filtration process. This work developed a novel chalcopyrite (CuFeS 2) incorporated catalytic ceramic membrane (CFSCM), and comprehensively evaluated the oxidation-filtration efficiency and mechanism of CFSCM/peroxymonosulfate (PMS) for organics removal and membrane fouling mitigation. Results showed that PMS activation was more efficient in the confined membrane pore structure. The CFSCM 50 /PMS filtration achieved almost complete removal of 4-Hydroxybenzoic acid (4-HBA) under the following conditions: pH = 6.0, C PMS = 0.5 mM, and C 4-HBA = 10 mg/L. Meanwhile, the membrane showed good stability after multiple uses. During the reaction, SO 4 •− and •OH were generated in the CFSCM 50 /PMS system, and SO 4 •− was considered to be the dominant reactive species for pollutant removal. The roles of copper, iron, and sulfur species, as well as the possible catalytic mechanism were also clarified. Besides, the CFSCM 50 /PMS catalytic filtration exhibited excellent antifouling properties against NOM with reduced reversible and irreversible fouling resistances. The Extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory analysis showed an increased in repulsive energy at the membrane-foulant interface in the CFSCM 50 /PMS system. Membrane fouling model analysis indicated that standard blocking was the dominant fouling pattern for CFSCM 50 /PMS filtration. Overall, this work demonstrates an efficient catalytic filtration process for foulants removal and outlines the synergy of catalytic oxidation and interface interaction. [ABSTRACT FROM AUTHOR]

To find out the effect of the rare earth doping element Holmium (Ho) on CuInS2 thin films, various studies have been carried out and the results have been reported in this paper. The PL study shows that intensity of doped film is more than undoped film. The PL emission peak appears at 570–580 nm. SEM images of CIS:Ho (4 ml) film shows agglomeration on the surface. Both synthesized film of CuInS2 appears to be amorphous in nature with chalcopyrite structure as clear from XRD. Hall measurement and optical studies were also performed. [ABSTRACT FROM AUTHOR]

The Kodaro–Udokan region is a huge Cu metallogenic province in Southern Siberia, one of the largest on Earth. It contains world-class copper sandstone-hosted Udokan (Cu reserves of 26.7 Mt) and PGE-Ni-Cu Chineysky deposits related to gabbro–anorthosite pluton (Cu—10 Mt; Fe-Ti-V, 30 Gt of ore). Furthermore, there are many small deposits of sulfide ores in sedimentary and igneous rocks in this region as well. For many decades, their genesis has been hotly debated. We studied the mineral composition and the sulfur isotopes in several deposits located at different levels of the stratigraphic sequence and in gabbro intruded in sandstones of the Udokan complex. The differences in ore compositions were found. The Burpala and Skvoznoy deposits consisting of the chalcocite–bornite association are characterized only by negative δ34S. The δ34S values for the Udokan deposits are mostly <0 (up to −28‰). The positive δ34S data characterize the ores of the Chineysky and Luktursky intrusions. Two Cu sandstone-hosted deposits are characterized by complex ore composition, i.e., the Krasny deposit, comprising chalcopyrite–pyrrhotite ores, is enriched in Co, Ni, Bi, Sb, Mo, Pb, Zn, Se, Te, and U and has a wide range of δ34S = −8.1–+13.5‰, and the Pravoingamakitsky deposit (Basaltovy section), consisting of quartz–chalcopyrite veins, has high PGE contents in ores with δ34S = +2.9–+4.0‰. These deposits are located near the gabbro massifs, and it is supposed that their ore compositions were influenced by magmatic fluids. The general regularities of the localization of the deposits in rift zones, and the proximity of mineral and isotopic composition allow us to conclude that the main source of copper could be rocks of basic composition because only they contain high Cu contents. Fluids from deep zones could penetrate to the surface and form Cu sandstone-hosted deposits. [ABSTRACT FROM AUTHOR]

The luminous transmittance and the color rendering index of daylight through semitransparent photovoltaic glazing are essential parameters for visual comfort indoors, and they must be considered for different absorber materials that were traditionally developed for opaque solar cells, such as those of the chalcopyrite type. With this aim, various chalcopyrite compounds (CuInSe2, CuInS2 and CuGaS2) were prepared by means of evaporation and then measured to obtain their optical absorption spectra. These experimental data are used here to calculate the solar absorptance (αS), luminous transmittance (τL) and color rendering index (Ra) as a function of the chalcopyrite film thickness. The comparative analysis of the different factors indicates that 70 nm thick CuInSe2 is optimal to guarantee excellent visual comfort (τL = 50% and Ra = 93%) while absorbing as much solar irradiance (αS = 37%) as 130 nm thick CuInS2 or 900 nm thick CuGaS2. The second option (130 nm thick CuInS2) is also considered good (τL = 40% and Ra = 80%), but for CuGaS2, the thickness should be kept below 250 nm in order to obtain a suitable color rendering Ra ≥ 60%. [ABSTRACT FROM AUTHOR]

S‐Fe‐Cu isotope systems are powerful tracers for revealing geochemical processes. However, the microanalysis of S‐Fe‐Cu isotopes is critically limited by the lack of suitable reference materials. Herein, we present three potential reference materials Ll‐Cpy (chalcopyrite), Ll‐Po (pyrrhotite) and Ll‐Sp (sphalerite) for in situ S‐Fe‐Cu isotope measurements. Numerous in situ S‐Fe‐Cu isotope measurements were performed over two years to assess isotopic homogeneity. The bulk S isotopic compositions were determined independently in seven laboratories by isotope ratio mass spectrometry (IRMS); the preferred δ34SV‐CDT for Ll‐Cpy, Ll‐Po, Ll‐Sp are 6.13 ± 0.37‰ (2s), 6.42 ± 0.37‰ (2s) and 6.28 ± 0.38‰ (2s), respectively. The bulk Fe isotope ratios in Fe‐bearing Ll‐Cpy and Ll‐Po were determined using solution nebulisation multi‐collector inductively coupled plasma‐mass spectrometry, and the obtained δ56FeIRMM‐014 values are 0.57 ± 0.07‰ (2s) and ‐0.62 ± 0.07‰ (2s), respectively. The mean bulk δ65CuNIST SRM 976 value of Ll‐Cpy is 0.57 ± 0.06‰ (2s). All the bulk values are in good agreement with the long‐term statistical results of laser ablation‐MC‐ICP‐MS and proposed as the recommended values. These sulfides are well characterised and isotopically homogeneous (at 30–40 μm spatial resolution), and can be used as potential calibration materials for in situ S‐Fe‐Cu isotope measurements. [ABSTRACT FROM AUTHOR]

The separation of chalcopyrite and pyite is not fully solved, and thus more efficient depressants are still needed in industry. This paper used potassium permanganate (KMnO4) as a pyrite depressant to separate pyrite from chalcopyrite. Flotation and contact angle results indicated that pyrite could be depressed by KMnO4 at pH 7, while KMnO4-treated chalcopyrite could be floated by sodium ethylxanthate. For the pyrite-chalcopyrite mixture, the recovery of chalcopyrite was nearly 95% and that of pyrite was less than 15% when minerals were reacted with 4 × 10−4 KMnO4 for 3 min. The KMnO4-treatment raised the zeta potential of pyrite at pH 7, which may generate oxidized species on the pyrite surface. The oxidation products on the pyrite surface were FeO, FeOOH, and Fe2(SO4)3 as determined by XPS analyses. These oxidation products were well coated on the pyrite surface, which dramatically lowers the hydrophobicity of pyrite. In contrast, in the case of chalcopyrite, KMnO4 treatment did not generate new oxidation components on its surface, causing the chalcopyrite surface to remain hydrophobic and allowing the flotation of chalcopyrite by air bubbles. Thus, pyrite could be efficiently separated from chalcopyrite using KMnO4 as a depressant. [ABSTRACT FROM AUTHOR]