Single-step synthesis of ternary metal chalcogenides (sf-CuInS2 and sf-CuInSe2) stripped off the organic cover and their use as a catalyst for symmetric Glaser-Hay coupling reactions

Generally, inorganic nano/microparticles produced by chemical routes are covered by organic surfactants or polymers to control their agglomeration during their synthesis. However, these surfactants and polymers negatively affect their catalytic activity because these molecules mask the surface. This work presents the synthesis of surfactant-free CuInS2 and CuInSe2 (sf-CuInS2 and sf-CuInSe2) nano/microparticles through simple reactions without surfactant or polymer coatings using LiBH4 under a thermodynamically favourable condition. These reactions are rare observations of a single-step process to produce ternary metal chalcogenides without any template assistance. We have also demonstrated efficient catalysis by sf-CuInS2 nanoparticles in the coupling reaction of substituted phenylacetylenes. We tested it as catalysts in dimerizing 1,3-diyne derivatives while using 8-diazabicyclo[5.4.0]undec-7-ene (DBU) as the base. These Glassar-Hay coupling reactions are conducted at room temperature in acetonitrile (4-7 h, depending on the substrate) using 10 mg of sf-CuInS2. The maximum yield obtained in these reactions is 97%, while the catalyst is reusable for five cycles with little difference in its ability to catalyse. The effectiveness of the catalyst is credited to the availability of a free catalytic surface.

Biocompatible CuInS2 Nanoparticles as Potential Antimicrobial, Antioxidant, and Cytotoxic Agents

A simple hydrothermal route is employed to synthesize pure copper indium disulfide (CIS) and CIS nanoparticles (NPs) mediated by various natural plant extracts. The plant extracts used to mediate are Azadirachta indica (neem), Ocimum sanctum (basil), Cocos nucifera (coconut), Aloe vera (aloe), and Curcuma longa (turmeric). The tetragonal unit cell structure of as-synthesized NPs is confirmed by X-ray diffraction. The analysis by energy-dispersive X-rays shows that all the samples are near-stoichiometric. The morphologies of the NPs are confirmed by high-resolution scanning and transmission modes of electron microscopy. The thermal stability of the synthesized NPs is determined by thermogravimetric analysis. The optical energy band gap is determined from the absorption spectra using Tauc's equation. The antimicrobial activity analysis and the estimation of the minimum inhibitory concentration (MIC) value of the samples are performed for Escherichia coli, Pseudomonas aeruginosa, Proteus vulgaris, Enterobacter aerogenes, and Staphylococcus aureus pathogens. It shows that the aloe-mediated CIS NPs possess a broad inhibitory spectrum. The best inhibitory effect is observed against S. aureus, whereas the least effect was exhibited against P. vulgaris. The least MIC value is found for aloe-mediated CIS NPs (0.300 mg/mL) against S. aureus, P. aeruginosa, and E. aerogenes, along with basil-mediated NPs against E. coli. The antioxidant activity study showed that the IC50 value to inhibit the scavenging activity is maximum for the control (vitamin C) and minimum for pure CIS NPs. The in vivo cytotoxicity study using brine shrimp eggs shows that the pure CIS NPs are more lethal to brine shrimp than the natural extract-mediated CIS NPs. The in vitro cytotoxicity study using the human lung carcinoma cell line (A549) shows that the IC50 value of turmeric extract-mediated CIS NPs is minimum (15.62 ± 1.58 μg/mL). This observation reveals that turmeric extract-mediated CIS NPs are the most potent in terms of cytotoxicity toward the A549 cell line.

The Photoluminescence and Biocompatibility of CuInS2-Based Ternary Quantum Dots and Their Biological Applications

Semiconductor quantum dots (QDs) have become a unique class of materials with great potential for applications in biomedical and optoelectronic devices. However, conventional QDs contains toxic heavy metals such as Pb, Cd and Hg. Hence, it is imperative to find an alternative material with similar optical properties and low cytotoxicity. Among these materials, CuInS2 (CIS) QDs have attracted a lot of interest due to their direct band gap in the infrared region, large optical absorption coefficient and low toxic composition. These factors make them a good material for biomedical application. This review starts with the origin and photophysical characteristics of CIS QDs. This is followed by various synthetic strategies, including synthesis in organic and aqueous solvents, and the tuning of their optical properties. Lastly, their significance in various biological applications is presented with their prospects in clinical applications.

Mechanochemical Synthesis and Characterization of CuInS₂/ZnS Nanocrystals

In this study, CuInS₂/ZnS nanocrystals were synthesized by a two-step mechanochemical synthesis for the first time. In the first step, tetragonal CuInS₂ was prepared from copper, indium and sulphur precursors. The obtained CuInS₂ was further co-milled with zinc acetate dihydrate and sodium sulphide nonahydrate as precursors for cubic ZnS. Structural characterization of the CuInS₂/ZnS nanocrystals was performed by X-ray diffraction analysis, Raman spectroscopy and transmission electron microscopy. Specific surface area of the product (86 m²/g) was measured by low-temperature nitrogen adsorption method and zeta potential of the particles dispersed in water was calculated from measurements of their electrophoretic mobility. Optical properties of the nanocrystals were determined using photoluminescence emission spectroscopy.

Compound Copper Chalcogenide Nanocrystals

This review captures the synthesis, assembly, properties, and applications of copper chalcogenide NCs, which have achieved significant research interest in the last decade due to their compositional and structural versatility. The outstanding functional properties of these materials stems from the relationship between their band structure and defect concentration, including charge carrier concentration and electronic conductivity character, which consequently affects their optoelectronic, optical, and plasmonic properties. This, combined with several metastable crystal phases and stoichiometries and the low energy of formation of defects, makes the reproducible synthesis of these materials, with tunable parameters, remarkable. Further to this, the review captures the progress of the hierarchical assembly of these NCs, which bridges the link between their discrete and collective properties. Their ubiquitous application set has cross-cut energy conversion (photovoltaics, photocatalysis, thermoelectrics), energy storage (lithium-ion batteries, hydrogen generation), emissive materials (plasmonics, LEDs, biolabelling), sensors (electrochemical, biochemical), biomedical devices (magnetic resonance imaging, X-ray computer tomography), and medical therapies (photochemothermal therapies, immunotherapy, radiotherapy, and drug delivery). The confluence of advances in the synthesis, assembly, and application of these NCs in the past decade has the potential to significantly impact society, both economically and environmentally.

l-Cysteine assisted-synthesis of 3D In2S3 for 3D CuInS2 and its application in hybrid solar cells

Hierarchical CuInS₂ is synthesized with hierarchical In₂S₃ as the template, which is applied in MEH-PPV/CuInS₂ hybrid solar cells firstly.

Recent developments in the synthesis of nanostructured chalcopyrite materials and their applications: a review

Nanostructured chalcopyrites: synthesis and applications.

Semiconductor nanostructure-based photovoltaic solar cells

Substantial efforts have been devoted to design, synthesize, and integrate various semiconductor nanostructures for photovoltaic (PV) solar cells. In this article, we will review the recent progress in this exciting area and cover the material chemistry and physics related to all-inorganic nanostructure solar cells, hybrid inorganic nanostructure-conductive polymer composite solar cells, and dye-sensitized solar cells.

Synthesis of CuInS2 Microspheres using In2S3 Microspheres as Templates

CuInS2 microspheres have been prepared via a solvothermal route employing synthetic In2S3 microspheres as templates. X-ray diffraction analysis reveals that CuInS2 crystals assembled from In2S3 microsphere building blocks are tetragonal phase. Field emission scanning electron microscopy and transmission electron microscopy images show that the prepared CuInS2 microspheres are constructed by nanosheets. The evolution of crystal structure could be attributed to Cu+ ions inserted into the In2S3 microsphere templates, such that some In3+ ions were replaced and tetragonal CuInS2 crystals were formed during the solvothermal process.

Solution−Liquid−Solid Growth of Semiconductor Nanowires

The serendipitously discovered solution-liquid-solid (SLS) mechanism has been refined into a nearly general synthetic method for semiconductor nanowires. Purposeful control of diameters and diameter distributions is achieved. The synthesis proceeds by a solution-based catalyzed-growth mechanism in which nanometer-scale metallic droplets catalyze the decomposition of metallo-organic precursors and crystalline nanowire growth. Related growth methods proceeding by the analogous vapor-liquid-solid (VLS) and supercritical fluid-liquid-solid (SFLS) mechanisms are known, and the relative attributes of the methods are compared. In short, the VLS method is most general and appears to afford nanowires of the best crystalline quality. The SLS method appears to be advantageous for producing the smallest nanowire diameters and for variation and control of surface ligation. The SFLS method may represent an ideal compromise. Recent results for SLS growth are summarized.