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CuIn(S,Se) sub(2) thin films were grown on soda-lime glass substrates by one-step evaporation Cu-In precursors processes. Effects of synthesis temperature on the structural and optical properties of CuIn(S,Se) sub(2) absorption layers were studied. The changes of surface morphology among different samples were observed by field-emission scanning electron microscopy. From X-ray diffraction images and Raman spectra, the CuIn(S,Se) sub(2) films had good crystallinity quality when the synthesis temperature was 550 degree C. The FWHM of (112) peaks decreased from 0.537 degree to 0.180 degree , and secondary phase Cu sub(x)(S,Se) disappeared when the synthesis temperature increased from 300 to 550 degree C. The Raman spectra of the films also showed the CuIn(S,Se) sub(2) A sub(1) mode peaks existed chalcopyrite, and the blue shift of the CuIn(S,Se) sub(2) A sub(1) mode peaks from 289 to 284 cm super(-1). The optical properties of the films were showed by transmission spectra, and the energy band gap of the CuIn(S,Se) sub(2) thin films fabricated at 550 degree C is 1.34 eV.

In the present work an intense bibliographic search is developed, with updated information on the microscopic fundamentals that govern the behavior of flotation operations of chalcopyrite, the main copper mineral in nature. In particular, the effect caused by the presence of pyrite, a non-valuable mineral, but challenging for the operation due to its ability to capture a portion of collector and float, decreasing the quality of the concentrate, is addressed. This manuscript discusses the main chemical and physical mechanisms involved in the phenomena of reagent adsorption on the mineral surface, the impact of pH and type of alkalizing agent, and the effect of pyrite depressants, some already used in the industry and others under investigation. Modern collector reagents are also described, for which, although not yet implemented on an industrial scale, promising results have been obtained in the laboratory, including better copper recovery and selectivity, and even some green reagents present biodegradable properties that generate a better environmental perspective for mineral processing.

Design and fabrication of new infrared (IR) nonlinear optical (NLO) materials with balanced properties are urgently needed since commercial chalcopyrite‐like (CL) NLO crystals are suffering from their intrinsic drawbacks. Herein, the first defect‐CL (DCL) alkali‐earth metal (AEM) selenide IR NLO material, DCL‐MgGa2Se4, has been rationally designed and fabricated by a structure prediction and experiment combined strategy. The introduction of AEM tetrahedral unit MgSe4 effectively widens the band gap of DCL compounds. The title compound exhibits a wide band gap of 2.96 eV, resulting in a high laser induced damage threshold (LIDT) of ≈3.0 × AgGaS2 (AGS). Furthermore, the compound shows a suitable second harmonic generation (SHG) response (≈0.9 × AGS) with a type‐I phase‐matching (PM) behavior and a wide IR transparent range. The results indicate that DCL‐MgGa2Se4 is a promising mid‐to‐far IR NLO material and give some insights into the design of new CL compound with outstanding IR NLO properties based on the AEM tetrahedra and the structure predication and experiment combined strategy. The first defect‐chalcopyrite‐like alkali‐earth metal selenide IR NLO material DCL‐MgGa2Se4 with balanced SHG response and band gap is rationally designed and fabricated by a calculation and experiment combined strategy.

Speckling of sphalerite with micrometer-sized blebs of chalcopyrite is usually referred to as \"chalcopyrite disease.\" Fe-rich sphalerites are particularly prone to chalcopyrite disease. Considering the low degree of solid solution between sphalerite and chalcopyrite, exsolution is discarded as a process to explain the development of chalcopyrite disease. Diffusion-controlled replacement of Fe by Cu, and sphalerite-chalcopyrite co-precipitation are invoked as the most probable mechanisms. Although metamorphism is expected to dispel inhomogeneities through recrystallization, chalcopyrite disease interestingly appears unaffected and to be quite common in metamorphosed sulfide ores. We have conducted experiments on different bulk compositions in the system ZnS-PbS-FeS-Cu2S-As2S3 at 600 °C and annealed the run products containing melt at 350 °C to evaluate the role of sulfide partial melting, if any, in the development of chalcopyrite disease. The results indicate that chalcopyrite blebs developed only in those sphalerites that contained Fe and in which S atoms were in excess over Fe + Zn atoms. Also it was observed that the occurrence of Fe-bearing sphalerite and the sulfide partial melt (that invariably was S-deficient and Cu-enriched) in direct contact with each other was necessary for the chalcopyrite blebs to form. We propose nonstoichiometry-driven diffusion of Cu as the mechanism and sulfide partial melting as the principal causative factor behind the development of chalcopyrite disease in sphalerite. Chalcopyrite disease thus may be used as an easily identifiable potential indicator of sulfide partial melting in metamorphosed base metal sulfide deposits.

Chalcopyrite-based solar cells have reached an efficiency of 23.35%, yet further improvements have been challenging. Here we present a 23.64% certified efficiency for a (Ag,Cu)(In,Ga)Se 2 solar cell, achieved through the implementation of a series of strategies. We introduce a relatively high amount of silver ([Ag]/([Ag] + [Cu]) = 0.19) into the absorber and implement a ‘hockey stick’-like gallium profile with a high concentration of Ga close to the molybdenum back contact and a lower, constant concentration in the region closer to the CdS buffer layer. This kind of elemental profile minimizes lateral and in-depth bandgap fluctuations, reducing losses in open-circuit voltage. In addition, the resulting bandgap energy is close to the local optimum of 1.15 eV. We apply a RbF post-deposition treatment that leads to the formation of a Rb–In–Se phase, probably RbInSe 2 , passivating the absorber surface. Finally, we discuss future research directions to reach 25% efficiency. Keller et al. use high-concentration silver alloying and steep gallium grading close to the back contact to minimize bandgap fluctuations and thus voltage losses, achieving 23.6% certified efficiency in Cu(In,Ga)Se 2 solar cells.

Reduction of nitroaromatics to the corresponding amines is a key process in the fine and bulk chemicals industry to produce polymers, pharmaceuticals, agrochemicals and dyes. However, their effective and selective reduction requires high temperatures and pressurized hydrogen and involves noble metal-based catalysts. Here we report on an earth-abundant, plasmonic nano-photocatalyst, with an excellent reaction rate towards the selective hydrogenation of nitroaromatics. With solar light as the only energy input, the chalcopyrite catalyst operates through the combined action of hot holes and photothermal effects. Ultrafast laser transient absorption and light-induced electron paramagnetic resonance spectroscopies have unveiled the energy matching of the hot holes in the valence band of the catalyst with the frontier orbitals of the hydrogen and electron donor, via a transient coordination intermediate. Consequently, the reusable and sustainable copper-iron-sulfide (CuFeS 2 ) catalyst delivers previously unattainable turnover frequencies, even in large-scale reactions, while the cost-normalized production rate stands an order of magnitude above the state of the art. A low-cost plasmonic photocatalyst based on earth-abundant metals (Fe, Cu) maximizes solar energy conversion due to the concerted interplay of energies and interactions between reactants and hot carriers, thus producing aromatic amines with a high yield.

The conversion efficiency of kesterite solar cells has been stagnated at 12.6% since 2013. In contrast to chalcopyrite solar cells, the performance of kesterite solar cells is seriously limited by heterojunction interface recombination. Here we demonstrate kesterite/CdS heterojunction is constructed on a Zn-poor surface due to the dissolution of Zn 2+ during chemical bath deposition. The occupation of Cd 2+ on the Zn site and re-deposition of Zn 2+ into CdS creates a defective and lattice-mismatched interface. Low-temperature annealing of the kesterite/CdS junction drives migration of Cd 2+ from absorber back to CdS and Zn 2+ from absorber bulk to surface, achieving a gradient composition and reconstructing an epitaxial interface. This greatly reduces interface recombination and improves device open-circuit voltage and fill factor. We achieve certified 12.96% efficiency small-area (0.11 cm 2 ) and certified 11.7% efficiency large-area (1.1 cm 2 ) kesterite devices. The findings are expected to advance the development of kesterite solar cells. The efficiency of kesterite solar cells has been stuck at 12.6% since 2013 due to challenges in controlling defects. Now Gong et al. present a low-temperature annealing of the kesterite/CdS junction to form an epitaxial interface with a low defect density, enabling 13%-efficiency devices.

Copper isotopes (δ65Cu) in hydrothermal fluids have the potential to provide information on ore‐forming processes occurring below the seafloor, but Cu isotope data from high‐temperature fluids are scarce. Here, we examine the extent to which coexisting sulfide minerals in a hydrothermal chimney can preserve fluid Cu isotope ratios using a fluid‐solid pair of a black smoker (333°C) from the Roman Ruins vent area (PACMANUS) in the Manus Basin. Two ca. 3 cm long transects through the chalcopyrite‐rich chimney wall show an increase in δ65Cu from 0.48 to 2.28‰ from the interior to the exterior, coupled with limited variation in sulfide δ34S (1.52–4.72‰). The Cu isotopic composition of chalcopyrite from the innermost wall closely resembles the δ65Cu value of the paired hydrothermal fluid, indicating that chalcopyrite in the inner ∼5 mm of the chimney records the Cu isotope ratio of the venting fluid. Beyond this, an increase in sulfide δ65Cu toward the exterior correlates with an increase in the relative abundance of secondary Cu sulfides. The appearance of bornite coincides with the presence of small barite crystals, suggesting this represents a redox gradient between reduced hydrothermal fluids and oxidized seawater admixing inwards. Elevated δ65Cu in this zone can be explained by the precipitation of secondary Cu sulfides from 65Cu‐enriched fluids formed during oxidative chalcopyrite dissolution. Our findings indicate that interactions with oxidizing seawater shift chalcopyrite δ65Cu values over small spatial scales, and that caution must be applied if chimney sulfides are used to reconstruct δ65Cu values of high‐temperature hydrothermal fluids. Plain Language Summary Kilometers below the surface of the ocean, hydrothermal “chimney” structures emit hot and metal‐rich fluids from the seafloor. The chemical composition of these hot fluids can tell about the reactions that occur beneath the seafloor. In this study, we test how copper‐bearing minerals in a hydrothermal chimney record and preserve the copper isotopic composition of these hot fluids. To do so, we compare copper isotope ratios in a hydrothermal fluid and its paired chimney from a seafloor hot spring near Papua New Guinea and find that these ratios are very similar for minerals only in the innermost part of the chimney. Copper isotope ratios increase as the mineralogy of copper changes toward the outside of the chimney wall. This appears to result from cold seawater that enters the chimney and modifies the chemistry and mineralogy of the minerals in the structure. The resulting changes in copper isotope ratios within small cm‐scales of the chimney wall are as large as overall ranges observed in copper isotope ratios from seafloor hot springs globally. Therefore, our findings act as a cautionary tale for the use of chimney minerals to reconstruct the copper isotopic composition of hydrothermal fluids. Key Points Hydrothermal fluid Cu isotope ratios are preserved in chalcopyrite in the innermost part of a black smoker chimney Cu isotope ratios are altered by seawater‐driven oxidative dissolution of chalcopyrite and precipitation of bornite and chalcocite Bulk chimney Cu isotope ratios cannot be used as a record of fluid Cu isotope values

This research explored the physical properties of AuMTe 2 ( M  = Ga, In) chalcopyrite compound. We employ the full-potential linearized augmented plane wave (FP-LAPW) method in combination with the Tran-Blaha modified Becke–Johnson potential (TB-mBJ) as well as the generalized gradient approximation (GGA-PBE(96)), local density approximation (LDA) and Wu–Cohen generalized gradient approximation (WC-GGA) for the exchange–correlation potentials to analyze the structural, electronic and optical properties. The results are presented for lattice constant, bulk modulus, its pressure derivative, density of state (DOS) and optical properties. The structural and electronic outcomes obtained in this study align well with existing theoretical data. Our investigation revealed that the studied compounds exhibit a direct band gap, with average energy gaps of order of 0.281 eV for AuGaTe 2 and 0.092 eV for AuInTe 2 compounds, respectively. Optical properties, encompassing reflectivity R ( w ), absorption coefficient α ( ω ), refractive index n ( ω ), optical conductivity σ ( ω ), extinction coefficient k ( ω ) and energy loss function L ( ω ) are determined from real and imaginary parts of the computed dielectric function within the frameworks of the modified Becke–Johnson plus PBE-GGA(96), LDA and WC-GGA exchange–correlation potentials. The computed optical properties reveal minimal energy loss and reflectivity, alongside satisfactory absorption capability and optical conductivity within the infrared and visible spectral regions. These findings indicate potential applications in fields such as infrared absorption technologies and optoelectronic industries. This marks the initial quantitative theoretical forecast of the optical properties for these chalcopyrite compounds, necessitating experimental confirmation.

This study focuses on the beneficiation products of a sulfide copper ore from Yunnan. By integrating chemical multi-element analysis and TIMA (Tescan Integrated Mineral Analyzer) automated mineral quantitative analysis, the elemental distribution and mineral composition of the copper and sulfur concentrates were accurately determined. The results indicate that the primary copper mineral in the copper concentrate is chalcopyrite (62.84%), accompanied by a significant content of pyrite (29.07%), resulting in a copper grade of 22.06%. The sulfur concentrate is predominantly composed of pyrite (91.26%), with a copper content as low as 0.135%, demonstrating high efficiency in copper-sulfur separation. TIMA analysis further revealed key mineralogical factors affecting product quality, including the entrainment of pyrite and the distribution of gangue minerals. Based on these findings, process optimization strategies are proposed, including regrinding and optimization of depressant regimes to enhance concentrate grade, as well as pathways for the comprehensive recovery of associated valuable elements. This study provides essential mineralogical data and theoretical support for the efficient separation and comprehensive utilization of similar ores.