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Photocatalytic technology, as one of the most promising environmental remediation tools, has a wide range of applications in the field of removing antibiotic-based pollutants from wastewater. Therefore, to obtain efficient green and inexpensive photocatalysts, a p–n type Bi2MoO6/CuS composite photocatalyst modified by lignin carbon quantum dots (CQDs) was successfully prepared by solvothermal in situ co-precipitation in this study. It was used to achieve efficient photocatalytic degradation of tetracyclic hydrochloride antibiotics (TCH). The composites were systematically characterized by XRD, FTIR, XPS, SEM, TEM, EIS, nitrogen adsorption–desorption test, and UV–Vis DRS regarding crystal structure, microscopic morphology, and photoelectric properties. The results showed that the prepared samples had good crystallinity and high purity. The photocatalytic degradation experiments further demonstrated that the Bi2MoO6/CuS composites modified by CQDs exhibited excellent photocatalytic activity compared to Bi2MoO6 and CuS monomers wherein CQDs@Bi2MoO6/CuS 2 was the most effective, with a TCH removal of 96.98% and a degradation rate constant (K) of 0.04405 min−1 after 60 min of light exposure. The TCH removal could be maintained at 78.25% after four cycles. The ESR and LC–MS experiments demonstrated that h+ and ·O2− were the main active substances for photocatalytic degradation of TCH. This work provides an efficient catalyst for TCH removal and offers new ideas for applying p–n heterojunction composites in photocatalysis. [ABSTRACT FROM AUTHOR]

Chromium is a common heavy metal contaminant that is widely used in various industrial processes. CuS-Bi2WO6/CNFs composite photocatalysts with different CNFs(active carbon nanofibers) content were prepared by solvothermal method to improve the reduction of hexvalent chromium under visible light irradiation. The samples underwent characterization using XRD, SEM, TEM, XPS, UV–Vis, PL, and photocurrent techniques to analyze their crystal shape, morphology, structure, elemental composition, surface functional groups, and optical properties. Additionally, the photocatalytic reduction activity of Cr(VI) was investigated. The findings demonstrated a notably enhanced photocatalytic activity in CuS-Bi2WO6/CNFs composites compared to CuS, Bi2WO6, and CuS-Bi2WO6 individually. In the presence of visible light, 1% CuS-Bi2WO6/CNFs showed excellent photocatalytic activity for Cr(VI) reduction, with a reduction rate of 98% within 3 h. Furthermore, after four cycles, the 1% CuS-Bi2WO6/CNFs composite demonstrated consistent stability and recyclability. Additionally, an active group capture experiment revealed the involvement of hydroxyl radicals (•OH), photogenerated holes (h+), and superoxide radicals (•O2−) in the reduction of Cr(VI) by CuS-Bi2WO6/CNFs, with •O2− emerging as the primary active species in the system. Based on these findings, we investigated the photocatalytic reaction mechanism. This study underscores the feasibility of preparing CuS-Bi2WO6/CNFs through a straightforward and manageable solvothermal approach, affirming the promising potential of CuS-Bi2WO6/CNFs composites in hexavalent chromium treatment. [ABSTRACT FROM AUTHOR]

In this paper, a novel S-scheme CuS/Bi5O7I heterojunction was successfully constructed using a two-step approach comprising the alkaline hydrothermal method and the adsorption–deposition method, and it consisted of Bi5O7I microrods with CuS particles covering the surface. The photocatalytic antibacterial effects on Escherichia coli (E. coli) were systematically examined with visible light exposure. The results suggested that the 3%-CuS/Bi5O7I composite showed the optimal antibacterial activity, completely inactivating E. coli (5 × 108 cfu/mL) in 180 min of irradiation. Moreover, the bacterial inactivation process was scientifically described. •O2− and h+ were the major active species for the inactivation of the bacteria. In the early stages, SOD and CAT initiated the protection system to avoid the oxidative destruction of the active species. Unfortunately, the antioxidant protection system was overwhelmed thereafter, which led to the destruction of the cell membrane, as evidenced by the microstructure changes in E. coli cells. Subsequently, the leakage of intracellular components including K+, proteins, and DNA resulted in the unavoidable death of E. coli. Due to the construction of the S-scheme heterojunction, the CuS/Bi5O7I composite displayed the boosted visible light harvesting, the high-efficiency separation of photogenerated electrons and holes, and a great redox capacity, contributing to an outstanding photocatalytic disinfection performance. This work offers a new opportunity for S-scheme Bi5O7I-based heterojunctions with potential application in water disinfection. [ABSTRACT FROM AUTHOR]

There are growing interests in the development of bifunctional semiconducting nanostructures for photocatalysis and real-time monitoring of degradation process on catalysts. Defect engineering is a low-cost approach to manipulating the properties of semiconductors. Herein, we prepared CuS nanoplates by a hydrothermal method at increasing amounts of thioacetamide (CS-1, CS-2, and CS-3) and investigated the influence of sulfur vacancy (Vs) on surface-enhanced Raman spectroscopy (SERS) and photocatalysis performance. SERS intensity of 4-nitrobenzenethiol on CS-3 is 346 and 17 times that of CS-1 and CS-2, respectively, and enhancement factor is 1.34 × 104. Moreover, SERS is successfully applied to monitor the photodegradation of methyl orange. In addition, CS-3 also exhibited higher efficiency of Cr(VI) photoreduction than CS-1 and CS-2, and removal rate is 88%, 96%, and 73% under 2 h UV, 4 h visible, and 4 h near-infrared illumination, respectively. A systematic study including electron paramagnetic resonance spectra, photoelectrochemical measurements, and nitrogen adsorption isotherms were conducted to investigate the underlying mechanism. This work may help to understand the impact of vacancy defect on SERS and photocatalysis, and provide an effective and low-cost approach for the design of multifunctional materials. [ABSTRACT FROM AUTHOR]

To plan great photocatalytic performance, fast photo-generated charge recombination in nanocatalysts should be repressed. Thus, copper sulphide-Zirconium dioxide (CuS-ZrO2) nanocomposites were synthesised via a facile chemical method. The field-emission scanning electron microscopy (FESEM) results indicated that a heterojunctions interface among CuS and ZrO2. XRD analysis showed optimum CuS-ZrO2 photocatalyst with an average diameter of 42.58 nm were found. The UV–vis diffuse reflection spectroscopy (DRS) illustrated that the synthesised CuS-ZrO2 nanocomposites owned the highest absorption intensity in the UV-light range compared with pure ZrO2 nanoparticles. The bandgap (Eg) values of ZrO2 nanoparticles and CuS-ZrO2 nanocomposites were found 3.55 eV, and 2.65 eV, respectively. These characteristic structural and optical property consequence showed that the CuS-ZrO2 nanocomposites with great photocatalysis progress for degradation of tetracycline. Among the different ratio nanocomposites, CuS-ZrO2-2 indicates the highest photocatalytic efficiency (97.15%) in acidic pH and 60 min. Photocatalytic was optimised by response surface methodology with the Box-Behnken model. The study provides a promising photocatalyst to be used for organic pollutant removal in a large scale. [ABSTRACT FROM AUTHOR]

[Display omitted] • CuS/Bi 2 S 3 is prepared by a one-step hydrothermal method. • Heterojunctions are constructed between metal sulfides with narrow bandgaps. • The rate of CO generation from CuS/Bi 2 S 3 is 2.78 and 2.87 times higher than CuS and Bi 2 S 3. • Electron transmission channels promote the separation of photogenerated carriers. Enhancing the separation efficiency of photogenerated charge carriers and improving electron utilization are the primary challenges limiting the photocatalytic reduction performance. The utilization of heterojunctions to enhance the separation capability of photogenerated charge carriers, thereby increasing the product yield, is a common practice in the photocatalytic reduction of CO 2. In this work, a composite material of CuS and Bi 2 S 3 was synthesized via a one-step hydrothermal method, successfully constructing a Z-scheme heterojunction between the two materials. Under the influence of the heterojunction, CuS/Bi 2 S 3 overcame the predicament of rapid recombination of photogenerated charge carriers caused by the narrow bandgap of semiconductor materials. Facilitating the accumulation of electrons at reaction sites on CuS allows for their rapid participation in reactions, leading to increased production of CO 2 reduction products. The rate of CO generation from the photocatalytic conversion of CO 2 using CuS/Bi 2 S 3 was 108.57 μmol g−1h−1, representing an increase in the carbon monoxide yield by 2.78 times and 2.87 times compared to CuS and Bi 2 S 3 respectively, and CH 4 production of CuS/Bi 2 S 3 also increased. This study offers a new understanding of the construction of heterojunctions between metal sulfides. [ABSTRACT FROM AUTHOR]

In this paper, a novel S-scheme CuS/Bi5O7I heterojunction was successfully constructed using a two-step approach comprising the alkaline hydrothermal method and the adsorption–deposition method, and it consisted of Bi5O7I microrods with CuS particles covering the surface. The photocatalytic antibacterial effects on Escherichia coli (E. coli) were systematically examined with visible light exposure. The results suggested that the 3%-CuS/Bi5O7I composite showed the optimal antibacterial activity, completely inactivating E. coli (5 × 108 cfu/mL) in 180 min of irradiation. Moreover, the bacterial inactivation process was scientifically described. •O2− and h+ were the major active species for the inactivation of the bacteria. In the early stages, SOD and CAT initiated the protection system to avoid the oxidative destruction of the active species. Unfortunately, the antioxidant protection system was overwhelmed thereafter, which led to the destruction of the cell membrane, as evidenced by the microstructure changes in E. coli cells. Subsequently, the leakage of intracellular components including K+, proteins, and DNA resulted in the unavoidable death of E. coli. Due to the construction of the S-scheme heterojunction, the CuS/Bi5O7I composite displayed the boosted visible light harvesting, the high-efficiency separation of photogenerated electrons and holes, and a great redox capacity, contributing to an outstanding photocatalytic disinfection performance. This work offers a new opportunity for S-scheme Bi5O7I-based heterojunctions with potential application in water disinfection.

Composite heterostructure photocatalysts can effectively improve photocatalytic performance. For narrow‐bandgap semiconductors, such as Bi2S3, constructing heterostructures with other semiconductors can obviously promote the separation of photogenerated electron−hole pairs and improve their photocatalytic performance. However, some basic and important parts of this technology still require further clarification. Herein, the interface properties of CuS/Bi2S3 heterostructure was studied using density functional theory calculations. The results show that the electronic structure of the interface model shows some different characteristics compared with the bulk and surface models due to the different bonding modes and chemical environments at the interface. At the interface of the CuS/Bi2S3 heterostructure, the band edge of CuS is bent downward relative to Bi2S3 to form a type II heterostructure. In addition, in the equilibrium state, the direction of the built‐in electric field of the heterostructure is from Bi2S3 to CuS. Therefore, the photogenerated electron−hole pairs can be separated by the CuS/Bi2S3 interface, which is extremely advantageous for the improvement of photocatalytic performance. The formation of the CuS/Bi2S3 heterostructure not only broadens the light absorption of CuS but also suppresses the recombination of photogenerated electron−hole pairs of the narrow‐bandgap semiconductor Bi2S3. [ABSTRACT FROM AUTHOR]

There are growing interests in the development of bifunctional semiconducting nanostructures for photocatalysis and real-time monitoring of degradation process on catalysts. Defect engineering is a low-cost approach to manipulating the properties of semiconductors. Herein, we prepared CuS nanoplates by a hydrothermal method at increasing amounts of thioacetamide (CS-1, CS-2, and CS-3) and investigated the influence of sulfur vacancy (Vs) on surface-enhanced Raman spectroscopy (SERS) and photocatalysis performance. SERS intensity of 4-nitrobenzenethiol on CS-3 is 346 and 17 times that of CS-1 and CS-2, respectively, and enhancement factor is 1.34 × 104. Moreover, SERS is successfully applied to monitor the photodegradation of methyl orange. In addition, CS-3 also exhibited higher efficiency of Cr(VI) photoreduction than CS-1 and CS-2, and removal rate is 88%, 96%, and 73% under 2 h UV, 4 h visible, and 4 h near-infrared illumination, respectively. A systematic study including electron paramagnetic resonance spectra, photoelectrochemical measurements, and nitrogen adsorption isotherms were conducted to investigate the underlying mechanism. This work may help to understand the impact of vacancy defect on SERS and photocatalysis, and provide an effective and low-cost approach for the design of multifunctional materials.

Abstract CuS nanoflowers were loaded on anatase TiO2/polyvinylidene fluoride (PVDF) fibers by hydrothermal treated electrospun tetrabutyl orthotitanate (TBOT)/PVDF fibers at low temperature. The results indicated that the amount of copper source and sulfur source determined the crystallization and morphology of the resultant products. It was found that the composite of CuS narrowed the band gap energy of TiO2 and enhanced the separation efficiency of the photogenerated electron-hole pairs of TiO2. The photocatalytic reaction rate of CuS/TiO2/PVDF fibers to rhodamine B was 3 times higher than that of TiO2/PVDF fibers under visible light irradiation. Besides, owing to the preparation process was carried out at low temperature, the flexibility of CuS/TiO2/PVDF fibers was ensured. In addition, the self-cleaning performance of the dye droplets on the resultant product surface was demonstrated under visible light. Meanwhile, the resultant product can automatically remove dust on the surface of the material under the rolling condition of droplets due to its hydrophobicity. Therefore, the as-prepared CuS/TiO2/PVDF fibers can not only degrade the contaminated compounds, but also depress the maintenance cost owing to its self-cleaning performance, which means a very practical application prospect.

The thin films Fe doped copper sulphide Cu1−xFexS (CFS) (x = 0.01, 0.03, 0.05, and 0.07) were elaborated by spray pyrolysis deposition technique. The characterization by XRD and SEM of the thin films shows a Covellite CuS single phase without formation of other phases. The structure is a simple hexagonal with unit cell dimension, a = b = 3.79 Å and c = 16.34 Å. The Analysis of the UV–Vis spectra reveals that the energy band gap has been decreased from 2.47 to 1.98 eV with the increase of Fe concentration. The absorption coefficients of CFS films have increased from 1.155 × 105 to 1.712 × 105 cm−1. It has demonstrated that a right band gap with a right band edge alignment at a pH value for Fe-doped CFS can boost the material application as a photocatalyst for the visible light. According to this study, CFS (0.07) thin films for a pH = 3 solutions is a promising material for photocatalysis application for water splitting to hydrogen-oxygen production. Nevertheless, we demonstrate that the formation of straddling gap heterostructure for CuS and CFS for a pH solution between 7 and 8 induces the production of oxygen and hydrogen. [ABSTRACT FROM AUTHOR]

• CuS-AgVO 3 /Ag-TNR materials were fabricated via an ultra-sonication method. • AgVO 3 /Ag provides good stability, high conductivity and electron-storing capacity. • CuS acts as co-catalyst and suppress the charge carrier recombination. • CuS-AgVO 3 /Ag-TNR shows higher photocatalytic H 2 yield (756 µmol/g). • 1 wt% CuS-AgVO 3 /Ag-TNR heteronanostructure is stable for up to 15 h. Recently, the frenetic development of stable quaternary material with a wide range of solar energy absorption and separation of charge carrier has emerged as a favorable material for the solar-to-hydrogen conversion. In this work, quaternary CuS-AgVO 3 /Ag-TNR heteronanostructures (HNSs) synthesized by an ultra-sonication method for stabilized solar light photocatalytic hydrogen production in glycerol-water mixture. Among the prepared photocatalysts, the 1 wt% CuS-AgVO 3 /Ag-TNR HNS produced the highest H 2 activity (756 µmol/g), approximately 84 times greater than the TNR due to higher charge separation, excellent conductivity, plasmonic resonance effect, and electron-storing capacity. Interestingly, the accelerated charge transfer pathway through the Schottky junction between the AgVO 3 and Ag to the conduction band of the TNR and thereafter to the electron acceptor of CuS for the reduction of H+ ions to H 2. Additionally, a possible photocatalytic mechanism of CuS-AgVO 3 /Ag-TNR HNS for improved H 2 production was proposed based on the results obtained by various characterization techniques. Therefore, present research work explores the new insights to design high-performance CuS-AgVO 3 /Ag-TNR HNS material for the conversion of clean renewable H 2 energy for the futuristic transport applications. [ABSTRACT FROM AUTHOR]

The material of CuS/polyvinyl alcohol-chitosan (CuS/PVACS) was prepared with a novel synthesis analysis. The crystallinity, morphological characteristics, and photocatalytic performance of the nano-materials were investigated by X-ray diffraction, field emission scanning electron microscopy X-ray photoelectron, and UV–vis spectrophotometry. The band gap values (Eg) was found as 2.50, and 2.04 eV for CuS, and CuS/PVACS nano-catalyst, respectively. The photo-degradation amount of the malachite green solutions which were degraded by CuS/PVACS in the UV-irradiation in 60 min was above 96.51%. The antibacterial properties of the CuS/PVACS has been evaluated versus (G+/G-) bacteria. The results of antibacterial performance indicated that CuS/PVACS nanocomposites have bacteriostatic behavior versus Escherichia coli , Pseudomonas syringae , Staphylococcus aureus and Streptococcus pneumoniae. [ABSTRACT FROM AUTHOR]

This study presents the synthesis of nanocomposite namely n-type CeO 2 /p-type CuS heterojunctions as adsorbent/photocatalysts by electrospinning and hydrothermal methods with a low band gap. Photo-degradation of MB at various time under visible light radiation (LED) for calculating Langmuir–Hinshelwood (L–H) kinetics used. The influence of the operational parameters such as are pH, concentration of MB, amount of photocatalyst, and irradiation time investigated. Composite of n-type CeO 2 /p-type CuS heterojunctions as adsorbent/photocatalysts were successfully synthesized based on electrospinning technique, calcination and hydrothermal methods following growth of CuS nanostructures on the primary CeO 2 nanofibers, while laterally were characterized by FE-SEM, EDS, XRD, DRS and FT-IR. Present composite in aqueous solutions was applied for methylene blue (MB) degradation was investigated under visible light radiation (LED). DRS analysis illustrates that CeO 2 /CuS n–p heterojunction exhibited enhanced absorption in the visible region with band gap of 2.55. Under optimal conditions (3.0 mg L−1 MB, 1 g L−1 of CeO 2 /CuS dosage and 40 min irritation time at pH of 6.0) lead to 89.80% photocatalytic decomposition of MB. The CeO 2 /CuS composite nanofiber as photocatalyst exhibited enhanced visible-light absorption and reduced charge recombination, as compared to bare CeO 2 ribbon-like nanofibers, due to the interfacial charge transfer effect among the CuS species and CeO 2. The first-order kinetics based on Langmuir–Hinshelwood (L–H) model was able for effective fitting empirical data, while its rate constant (k obs), L–H rate constants (k r) and L–H adsorption constants (K A) were 0.0625 min−1, 0.157 mg min−1 L and 0.24 L mg−1 by CeO 2 /CuS in optimum condition. The reusability of CeO 2 /CuS composite is relatively undesirable in view of the recycling of photocatalysts. [ABSTRACT FROM AUTHOR]

Copper sulfide (CuS) was prepared by co-precipitation process at low temperature and atmospheric pressure without any additive while Cu(NO3)2 and thioacetamide were used as copper and sulfide sources, respectively. The effects of concentration, time, temperature, molar ratio of sulfur to copper and the pH of reaction system on the morphology of CuS were investigated. Rhodamine B (RhB) aqueous was employed to evaluate the photocatalysis and adsorption performances of the samples. The results showed that a pure hexagonal CuS has been successfully synthesized. Samples were demonstrated multifunctional of adsorption and photocatalysis under visible-light, which improved the degradation performance of high-dye wastewater. The degradation efficiency of RhB (20 mg L−1) was 99% in 120 min; when a small amount of H2O2 was used, 99% of RhB in high (50 mg L−1) wastewater can be removed within 60 min. This study provides a green preparation to choose for CuS with hollow spheres. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The CuS/Bi 4 Ti 3 O 12 p-n heterojunction material were synthesized. • Flower like hierarchical structures with improved visible light absorption. • Intra-electric field and microscopic contact are vital for photocatalytic activity. • CuS/Bi 4 Ti 3 O 12 materials highly active for MCPA degradation under visible light. • The mechanistic details of MCPA degradation is illustrated. Abstract In this study, a series of CuS/Bi 4 Ti 3 O 12 p-n heterojunction materials were synthesized by a two-step process. Initially, the Aurivillius phase Bi 4 Ti 3 O 12 (BT) was synthesized by a facile combustion route using urea as a fuel. The Bi 4 Ti 3 O 12 was subsequently modified by deposition of CuS (5–20 wt%) using a hydrothermal route to prepare the heterojunction materials. The methods of synthesis and calcination temperature were important factors which influenced the morphology, particle size and phase purity of Bi 4 Ti 3 O 12 material. Phase pure BT nanoplates with planar dimension of 150–200 nm and thickness between 50 and 70 nm were obtained at a calcination temperature of 600 °C. Pure CuS prepared by hydrothermal method, contained hierarchical microspheres with diameter in the range of 1.2–1.6 μm. The heterostructure materials exhibited hierarchical flower like structure consisting of ultrathin CuS nanosheets and BT-nanoflakes. HRTEM and microstructural study revealed microscopic close interaction between the two phases. The optical and electrical measurement study suggested significant improvement in visible light absorption (400–800 nm) and charge carrier separation due to heterojunction formation. The CuS/Bi 4 Ti 3 O 12 materials showed excellent photocatalytic activity for aqueous phase degradation of 2-methyl-4-chlorophenoxyacetic acid (MCPA) herbicide under visible light (>95% degradation in 3 h). The rate constant for CuS/Bi 4 Ti 3 O 12 materials was 4.5 times higher than the pure BT material towards MCPA degradation. The OH and O 2 – radicals have been identified as the reactive species, the formation of which was confirmed by spectrometric method using terephthalic acid and nitroblue tetrazolium as molecular probes. The mechanism of MCPA degradation over the photocatalyst surface has also been elucidated using LC-ESI-MS, TOC and scavenger experiments. [ABSTRACT FROM AUTHOR]

Abstract Semiconductor material with narrow bandgap is an ideal photo-thermal conversion material because of its high absorption intensity in infrared region. Here, CuS/TiO 2 composites were synthesized based on UV-responsive TiO 2 compound with narrow bandgap semiconductor material CuS for CO 2 conversion under full-spectrum irradiation. The experimental results showed that 2% CuS/TiO 2 exhibited higher photocatalytic CO 2 reduction efficiency due to the solar induced photo-thermal synergistic effect. CuS can absorb and convert infrared light into heat energy, which promotes the utilization range of sunlight for CO 2 conversion. In-situ Fourier transform infrared spectroscopy (FT–IR) was used to explain the photocatalytic mechanism at the molecular level. This work suggested a feasible way for integrated utilization of solar energy by narrow bandgap semiconductor compounds with TiO 2 to convert CO 2. Graphical abstract CuS/TiO 2 exhibited higher photocatalytic efficiency of CO 2 reduction due to the solar induced photo-thermal synergistic effect. Image 1 Highlights • CuS/TiO 2 composites were synthesized. • CuS/TiO 2 showed enhanced photo-thermal synergistic catalytic activity. • In-situ FT–IR was used to explain the photocatalytic mechanism. [ABSTRACT FROM AUTHOR]

In this study, Bi 2 O 2 CO 3 (BSC) nanoplates with high aspect ratio and hierarchical nanostructures were prepared by hydrothermal technique using urea/hexamethylenetetramine as hydrolysing agent and KCl as additive in different solvent systems. The relative molar proportion of urea and KCl was crucial for phase purity as well as thickness and planar dimension of the BSC plates. The BSC nanoplates were used as substrates to prepare CuS-Bi 2 O 2 CO 3 (CuS/BSC) direct z-scheme heterojunction systems. The heterojunction materials were characterized by FESEM, HRTEM, XRD, PL, FTIR and UV–Vis-DRS techniques. The presence of crystalline tetragonal BSC and hexagonal covellite CuS phase was inferred from XRD study. Morphologically, the CuS/BSC material contained CuS nanorods and BSC nanoplates. HRTEM study suggested microscopic close contact between the CuS nanorods and BSC nanoplates. Optical property study revealed improvement in visible light absorption and enhanced separation of excitons. The CuS/BSC materials were used as photocatalyst for chlorpyrifos pesticide degradation under visible light irradiation. The heterojunction materials were highly active achieving >95% degradation within 3 h of reaction. The pathway and mechanism of CP degradation was elucidated using GCMS and radical scavenger experiments. [ABSTRACT FROM AUTHOR]

The structural, compositional, electronic and luminescent properties of covelite (CuS) have been studied using copper acetate with the thiourea, in the presence of water-butanol and water-cyclohexanol as mixed solvents. The Hexagonal structure of the CuS samples was observed in the X-ray diffraction (XRD) pattern, which is due to different mixed solvents. The Cu S bond and atomic weight percentage were identified by the Fourier Transform Infrared (FT-IR) and Energy Dispersive X-ray (EDX) studies. The Scanning Electron Microscope (SEM) of CuS particles revealed the rod and flake shaped morphologies for water-butanol, and water-cyclohexanol, respectively. The bandgap energies of CuS nanostructures were calculated from the UV–Visible (UV–Vis) absorption spectra, and optical band energy curve. The UV and visible emission bands were observed from the PL spectra; this was due to the sulfur vacancy defects. From the CV study, it was found that the water-cyclohexanol assisted CuS sample has enhanced electrochemical properties than water-butanol assisted CuS sample. From the efficiency of the catalysts, the percentage degradation of the cango red (CR) dye was estimated from the mixed solvents assisted CuS samples. [ABSTRACT FROM AUTHOR]

Flower-like CuS microspheres were synthesised at 25 °C for 24 h in a choline chloride/ethylene glycol (1:3)-based deep eutectic solvent (DES) via an elemental-direct-reaction method. The as-synthesised CuS samples were characterised by XRD, SEM, EDS, TEM and UV–Vis diffuse reflectance spectra. Moreover, a detailed mechanism on the formation of a CuS flower-like structure has been elucidated. In addition, CuS microspheres exhibit high photocatalytic activity for the degradation of MB dye under visible light irradiation in the presence of H2O2. On the basis of the experimental results, a mechanism of photocatalysis also has been discussed. [ABSTRACT FROM PUBLISHER]

In this paper, we report systematic investigations on the effects of Ni doping on the structural, optical, magnetic and photocatalytic characteristics of CuS nanoparticles synthesized by simplistic wet chemical co-precipitation route via EDTA molecules as templates. XRD studies confirmed that accurate phase formation of synthesized nanoparticles and chemical composition were obtained by EDX. Magnetic measurements revealed that 3% Ni doped CuS nanoparticles show signs of good ferromagnetism at room temperature and transition of magnetic signs from ferromagnetic to paramagnetic nature by increasing the Ni dopant concentration in CuS host matrix. The photocatalytic degradation efficiency of the prepared pure and Ni doped CuS nanoparticles were evaluated as a function of simulated sunlight irradiation via RhB organic dye pollutant as a test molecule. Particularly, in the presence of 3% Ni doped CuS nanoparticles in pollutant solution 98.46% degradation efficiency was achieved within 60 min of sunlight irradiation; meanwhile bare CuS attained only 83.22%. Further, after five cycles 3% Ni doping CuS nanoparticles exhibit good photocatalytic stability with very negligible catalyst loss. We believe that the investigations in this study provides adaptable pathway for the synthesizing of various diluted magnetic semiconductor nanoparticles and their applications in spintronic devices as well as sunlight-driven photocatalysts intended for wastewater purification. [ABSTRACT FROM AUTHOR]

Robust TiO 2 /CuS@TiO 2 hetero-catalysts loaded on Ti mesh with outstanding photothermal effects for the photo-degradation of organic pollutions. [Display omitted] • TiO 2 /CuS@TiO 2 hetero-catalysts was in situ synthesized on titanium mesh for photocatalytic water treatment. • Effective utilization of incident light from UV to NIR was achieved due to the specific absorption of TiO 2 and CuS. • CuS serving as photothermal centers greatly enhanced the degradation rate of the photocatalytic centers (TiO 2). • Hetero-catalysts showed enhanced stability because of the protective TiO 2 layer by ALD technology. • Flow reactor made with 3D printing verified the potential of hetero-catalysts for large-scale applications. A scalable strategy with commercial feasibility was developed to in situ generate TiO 2 nanowires/amorphous CuS@TiO 2 nanolayer (TiO 2 /CuS@TiO 2) composites on the surface of titanium mesh through a sequent hydrothermal method, successive ionic layer adsorption and reaction (SILAR), and atomic layer deposition (ALD) techniques. The TiO 2 /CuS@TiO 2 composites could respectively harness the incident light with different spectra at the photothermal center (CuS, visible and near-infrared light) and photocatalytic center (TiO 2 , UV and visible light), which leads to the effective utilization of the solar energy. Benefiting from the CuS photothermal-induced local heating effect of CuS, the adjacent micro-zone temperature could be elevated and the activation energy barrier could be reduced by 10.5 kJ mol−1, which promotes the activation of surface lattice oxygen and dissolved oxygen in the photocatalytic process. Meanwhile, the ALD generated TiO 2 nanolayer could both serve as reactive centers but also protecting armor for the CuS, which prohibited the peeling and oxidation of the thermal centers, leading to a high stability of the photocatalyst, which exhibits no obvious fading after 20-cycle reuse. A flow reactor was conceived and made by 3D print and the Ti-mesh based photocatalyst was integrated, which demonstrates high photocatlytic performances, manifesting its great potential for large-scale water treatment. [ABSTRACT FROM AUTHOR]

Novel hierarchical polyaniline-modified CuS (PANI-CuS) has been synthesized by simple assembling PANI on the surface of flower-like CuS spheres. The PANI modification enhances the adsorption properties of flower-like CuS. The prepared PANI-CuS composites exhibit higher visible-light-driven photocatalytic activities in degradation of rhodamine B (RhB) than that of neat CuS. The unusual photocatalytic activity could be attributed to the great adsorptivity of dyes, the extended photoresponse range, and the high migration efficiency of photoinduced electrons, which may effectively suppress the charge recombination. This work not only provides a simple strategy for fabricating highly efficient and stable CuS-based composites, but also proves that these unique structures are excellent platforms for significantly improving their visible- light-driven photoactivities, holding great promise for their applications in the field of purifying polluted water resources. [ABSTRACT FROM AUTHOR]

Three-dimensional CuS hierarchical crystals with high catalytic activity had been successfully fabricated using a facile solvothermal process. The CuS microparticles showed different flower-like morphology and good dispersion by optimizing reaction conditions. It was found that using N,N-dimethylformamide (DMF) as the solvent reagent in the proper temperature conditions was favorable for the growth of hierarchically structured CuS. The hexagonal flower-like CuS synthesized at 170°C for 60 min displayed broad-spectrum photocatalytic properties under ultraviolet (UV) and visible irradiation. The as-prepared CuS crystals exhibited good performance to decolorize methylene blue (MB) solution under visible light irradiation. The total organic carbon (TOC) removal of rhodamine B (RhB) solution was nearly 60% after 5 h of the natural sunlight irradiation, and the property was stable after testing over four recycles, demonstrating a potential application in waster water treatment. [ABSTRACT FROM AUTHOR]

In this work, a novel organic–inorganic heterostructured photocatalyst: porous graphitic carbon nitride (g-C 3 N 4 ) hybrid with copper sulfide (CuS) had been synthesized via a precipitation-deposition method at low temperature for the first time. UV–vis spectroscopy revealed the porous g-C 3 N 4 /CuS nanocomposites showed a strong and broad visible light absorption. Furthermore, the g-C 3 N 4 /CuS nanocomposites showed higher photocatalytic activity in the photodegradation of various organic dyes than that of pure g-C 3 N 4 and CuS, and the selected sample of g-C 3 N 4 /CuS-2 exhibited the best photocatalytic activity under visible light. The good photocatalytic activity could be ascribed to the matching of the g-C 3 N 4 and CuS band gap energies. Besides, photoluminescent spectra and photoelectrochemical measurements also proved that the CuS/g-C 3 N 4 could greatly enhance the charge generation and suppress the charge recombination of photogenerated carriers. According to the experimental result, a possible photocatalytic mechanism has been proposed. Due to the high stability, the porous g-C 3 N 4 /CuS could be applied in the field of environmental remediation. Our work highlights that coupling semiconductors with well-matched band energies provides a facile way to improve the photocatalytic activity. [ABSTRACT FROM AUTHOR]

CuS nanoflowers, fabricated by an element-direct-reaction route using copper and sulfur powder, were loaded on rutile TiO 2 (CuS/TiO 2 ) at low temperature. CuS/TiO 2 composites were utilized as the photocatalysts for the degradation of Methylene Blue (MB) and 4-chlorophenol (4-CP). X-ray diffraction (XRD), UV Raman spectroscopy, transmission electron microscopy (TEM), XPS, and UV-visible diffuse reflectance spectra were used to characterize the crystalline phase, morphology, particle size, and the optical properties of CuS/TiO 2 samples. It is found that CuS/TiO 2 photocatalyst, which CuS are loaded on the surface of rutile TiO 2 , exhibited enhanced photocatalytic degradation of MB (or 4-CP) than TiO 2 or CuS. This indicates that CuS can enhance effectively the photocatalytic activity of rutile TiO 2 by forming heterojunction between CuS and rutile TiO 2 , which is confirmed by photoluminescence (PL) spectra and TEM. Moreover, CuS content has a significant influence on photocatalytic activity and 2 wt% CuS/TiO 2 showed the maximum photocatalytic activity for degradation of MB. [ABSTRACT FROM AUTHOR]

Morphologically controllable copper sulfide (CuS) nanoneedle, nanowall, and nanosheet networks on copper substrates have been fabricated by a simple, facile, and fast method based on low-temperature chemical vapor deposition through simply adjusting the reaction conditions such as the temperature and flow rate of argon gas. The compositional and structural analyses indicated that all the obtained nano-networks were single-crystalline. And their growths were possibly controlled by a solid–liquid–solid mechanism. The photocatalytic activities of the different shaped CuS nanostructures have been evaluated by their photodegradation on rhodamine B and methylene blue in aqueous phase, which revealed that in both cases the CuS nanoneedles nano-network exhibited better performance than the other two nanostructures. [ABSTRACT FROM PUBLISHER]

Highlights: [•] CuO/Al2O3 microspheres with cauliflower-like have been fabricated. [•] CuO/Al2O3 have been scarcely used as catalyst in photocatalytic process. [•] Pt and CuS deposited into CuO/Al2O3 obviously enhances the photocatalytic activity. [•] The maximum H2 evolution rate was obtained using oxalic acid as sacrificial reagent. [Copyright &y& Elsevier]

Abstract: The photocatalytic hydrogen production in the sacrificial S2−–SO3 2− anions was investigated with ZnO in the addition of metal sulfides containing Ag2S, CuS, Fe2S3, and NiS. In the absence of metal sulfides, the photocatalytic H2 evolution using ZnO was observed with 255 μmol g−1. The CuS amount and the concentrations of S2− and SO3 2− ions were optimized. It was found that ternary component semiconductor CuS/ZnS/ZnO was formed during the photocatalytic hydrogen production in the aqueous Na2S + Na2SO3 solution. The photocatalytic hydrogen evolution with CuS/ZnS/ZnO in the 0.4 M Na2S–0.4 M Na2SO3 solution was more than about 8.5 times better compared with those obtained with only ZnO. The CuS clusters on the surface of ZnS/ZnO seem to play an important role on the separation for electron–hole pair and the enhancement of H2 production. Nano-sized ZnS/ZnO photocatalytic hydrogen technology has great potential for low-cost, environmentally friendly solar-hydrogen production to support the future hydrogen economy. [Copyright &y& Elsevier]

A series of CuS nanostructures were synthesized by a simple wet chemical method on a large scale in the presence of cetyltrimethylammonium bromide at low temperature. Three typical samples were selected to study the relationship between the morphologies and resulting physical properties. The optical properties of CuS hierarchical structures were investigated by UV/Vis and Raman spectroscopy and the excellent photocatalytic performance was also evaluated by measuring the decomposition rate of methylene blue under natural light. As an absorber, the selected CuS nanostructures possess excellent microwave absorbing properties. When the thickness of the absorber is 3.5 mm, the minimum reflection loss can reach −76.4 dB at 12.64 GHz. The enhanced photocatalytic performance and microwave absorbing properties were also explained based on morphologies of the nanostructures. [ABSTRACT FROM AUTHOR]

Abstract: The controlled synthesis of CuS nanomaterials with hierarchical structures has been realized by chemical synthesis between copper nitrate trihydrate and thiourea via a solvothermal route. X-ray diffraction, scanning electron microscopy, and transmission electron microscopy were used to characterize the products. It was shown that CuS nanomaterials with hierarchical structures were composed of numerous nanoplates or nanorods. Experiments demonstrated that the morphologies of CuS nanomaterials were significantly influenced by reaction temperature, growth time and sulfur sources. A growth model was proposed for the selective formation of CuS hierarchical structures. The optical properties of the CuS hierarchical structures were investigated by ultraviolet–visible spectroscopy and photoluminescence spectroscopy. The ultraviolet–visible spectrum had a broad absorption in the visible range and the photoluminescence spectrum showed a strong green emission. Photocatalytic performance of the CuS hierarchical structures was evaluated by measuring the decomposition rate of methylene blue solution under natural light. The CuS hierarchical structures showed good photocatalytic activity. [Copyright &y& Elsevier]

The investigation on the degradation of water-soluble dye Brilliant green was done by using CQDs@CuS. Water-dissolvable, green incandescent CQDs (carbon quantum dots) were fabricated with a high yield by carbonization of water hyacinth (Eichhornia crassipes) weed for the first time at a mild temperature without using any surface activating reagents or salt. The sol-gel method was utilized for the fabrication of copper sulfide (CuS) nanoparticles. An attempt was made to synthesize a composite of CuS NPs with CQDs. The structural and composition determination of synthesized CuS, CQD, and composite (CQDs/CuS) was done by HRTEM, FESEM, XRD, XPS, FTIR, BET, and EDS techniques. TEM and XRD studies are congruent with the amorphous and hexagonal structure of CQDs and CuS, respectively. Various quality parameters such as DO (dissolved oxygen), COD (chemical oxygen demand), conductivity, salinity, and TDS (total dissolved solids) have been measured to observe the extent of degradation of dye. The comparative study has proven that composite (CQDs/CuS) have shown the greatest photocatalytic action for the dilapidation of Brilliant green than CuS NPs only. The probable trail of the dilapidation of dye has also been suggested. [Display omitted] • CQDs were prepared by Water hyacinth. • Prepared CQDs were composited with CuS for the removal of pollutants. • Green routes were employed. • BG is degraded completely using the prepared composite. • A sustainable way of removal of pollutants by the use of weed. [ABSTRACT FROM AUTHOR]

ZnAl 2 O 4 /CuS nanocomposite micro-flakes were prepared using a hydrothermal method. The as-prepared catalyst was investigated using X-ray diffraction, Fourier transform infrared spectra, scanning electron microscopy and UV–vis diffusive reflectance spectroscopy. X-ray diffraction analysis revealed the presence of CuS phase as a major phase (70%) in the prepared catalyst. The results indicated that the combination of ZnAl 2 O 4 with CuS ameliorate potentially its photocatalytic efficiency during the degradation of acid red 1 (95% within 150 min) under ultraviolet illumination compared to ZnAl 2 O 4 or CuS alone. The effect of catalyst mass, dye concentration and pH solution were investigated using ZnAl 2 O 4 /CuS. On the other hand, the reuse tests of ZnAl 2 O 4 /CuS displayed high-performance stability after five cycles. Additionally, the activity of hydroxyl radicals (OH. ) and superoxide ions (O 2 ·-) as the spices responsible for AR1 dye degradation was confirmed by the free radicals scavenging tests. [Display omitted] • Synthesis and characterization of the nanocomposite ZnAl 2 O 4 /CuS. • Effect of the addition of CuS on photocatalysis degradation of acid red 1. • Effect of the specific surface area, crystallite size, phase percentage on the efficiency of the photocatalyst. • High degradation efficiency of acid red 1 was achieved using ZnAl 2 O 4 /CuS than ZnAl 2 O 4 or CuS alone. • The photo-degradation of Acid Red 1 using ZnAl 2 O 4 /CuS is dominant by the OH. and O 2 -. radicals. [ABSTRACT FROM AUTHOR]

• Au-Ag/CuS nanoparticles by hydrothermal and reduction technique. • The Au-Ag/CuS nanoparticles was used for detection of trivalent chromium. • The Ag-Au NPs catalyst was used to degradation of amoxicillin. • The particles exhibited excellent antibacterial activities. In this project, bimetallic Au-Ag nanoparticles/CuS nanoparticles were prepared via simple hydrothermal methods, which were used as highly efficient material for Cr (III) detection, photocatalytic, and biological process. The Au-Ag/CuS nanoparticles was studied via UV–visible spectroscopy, field-emission scanning electron microscopy, Dynamic light scattering, and X-ray diffraction. The zeta potential and effective size of Au-Ag/CuS nanoparticles was −32.1 mV and 25 nm respectively. The response time of Cr (III) ions interaction was 2 min. The lowest detection of Cr (III) by Au-Ag/CuS nanoparticles was 0.5 nM. The Au-Ag/CuS nano catalyst was applied to decomposition of drug under visible lamp irradiation. The photo degradation response of drug was 100.0% in 30 min irradiation. The particles exhibited excellent antibacterial activities. [ABSTRACT FROM AUTHOR]

In this paper, copper base sulfide nanoparticles (Cu 2 S, CuS, CuO/Cu 2 O/Cu 2 S, Cu 2 S/CuS, CuS/S) were synthesized in polyethylene glycol (PEG)-400 by a one-step method and by tuning the molar ratios of Cu:S (1:0.1–1:3) with copper acetate and sublimed sulfur as sources. The interaction of elemental sulfur with copper ion in PEG was analyzed in detail to elucidate the formation mechanism. With the change of the molar ratio of copper to sulfur, the products exhibit a variety of composition, morphology and size. When the molar ratio of copper to sulfur is 1:1, the product is CuS nanoflakes with particle size of 200–300 nm and thickness of 30 nm. The CuS nanoflakes with a smaller band gap value of 2.01eV can photodegrade 96% (48 mg/g) of rhodamine B (RhB) in 5 min in the presence of H 2 O 2. This route is simple, environmentally friendly and it offers a more promising way to prepare different morphologies and compositions of Copper Base Sulfide Nanoparticles (CBSN). Image 1 • Copper Base Sulfide Nanoparticles were synthesized by a simple and green method. • The ratios of precursors determine the composition and morphology of the products. • The products exhibit good photocatalytic activity under visible irradiation. • The interaction of sulfur with copper ion in PEG was analyzed in detail. [ABSTRACT FROM AUTHOR]

• CuS NPs have been embedded in HKUST-1 via simple in-situ sulfuration. • HKUST-1 provided a suitable framework for CuS NPs to work efficiently. • CuS@HKUST-1 exhibited prominent photothermal performance under NIR light. • CuS@HKUST-1 showed an effective photocatalytic performance under NIR light. • CuS@HKUST-1 showed antibacterial efficacy of 99.7 % within 20 min NIR irradiation. Some new kinds of antibiotics-free antibacterial agents are required to deal with bacterial infections due to the occurrence of drug-resistance. In this work, Cu-based metal-organic framework (HKUST-1) embedded with CuS NPs were fabricated via a simple in-situ sulfuration process. The synthesized MOFs exhibited an highly effective disinfection efficacy of 99.70 % and 99.80 % against Staphylococcus aureus and Escherichia coli within 20 min irradiation of near-infrared (NIR) light, respectively, which was ascribed to the cooperative effects of photodynamic and photothermal effects of the composites. A certain amount of Cu2+ ions of the MOFs were reacted to form CuS NPs, which endowed this composite with outstanding photocatalytic and photothermal performance during NIR light irradiation. Moreover, HKUST-1 that composed of low toxic organic ligand 1,3,5-benzenetricarboxylic acid (H 3 BTC) coordinating copper ions could be a controllable carrier that imposed certain constraint on the NPs. Hence, these CuS@HKUST-1 would be a promising bioplatform for rapid bacteria-killing. [ABSTRACT FROM AUTHOR]

• CuS/CaCO 3 nanocomposite with NIR absorption was synthesized by using eggshell as template. • The effects of several free radicals on catalytic properties of nanomaterials induced by NIR light were discussed. • The bactericidal effect of ROS on bacteria was discussed. • CuS/CaCO 3 nanocomposite has enhanced catalytic and antibacterial properties when triggered by NIR light. The full utilization of sunlight and design of high-efficient and low-cost photocatalysts with robust stability for wastewater treatment is still a challenging task. Herein, we report an economic and simple strategy to prepare a novel photocatalyst by using eggshell as template and support. Rod-like Copper sulphide (CuS) nanoparticles are uniformly coated on the surface of porous eggshell to form CaCO 3 /CuS nanocomposite. Under NIR irradiation, the nanocomposite shows a high catalytic activity for 4-nirophenol (4-NP) reduction and strong photothermal ablation behavior against bacteria. A 98% degradation rate can be completed in 15 min, superior to that in the absence of Near-infrared (NIR) light irradiation. Bacterial inactivation ability is also closely related with photocatalyst concentrations and NIR power. A possible mechanism is suggested, which is attributed to the synergistic photocatalytic, photothermal, photodynamic effects. Our study indicates that waste eggshell not only can be used as an efficient support to immobilize nanoparticles, but also can act as reaction resource to provide active carbonate radicals (CO 3 −), which play an important role on target degradation molecules. [ABSTRACT FROM AUTHOR]

CuS/CuO nanowire heterostructures grown on copper mesh (CuS/CuO/Cu) have been successfully synthesized by a liquid–solid reaction at room temperature followed by annealing. The proposed structure has been verified by X-ray diffraction analysis. Scanning electron microscopy images have indicated that the density and diameter of CuS nanoparticles on CuO nanowires can be tuned by controlling the duration of sulfonation with Na 2 S. Photocatalytic studies have revealed that CuS/CuO/Cu heterostructures offer improved photocatalytic activity in the degradation of Methylene Blue (MB) in the presence of H 2 O 2. A sample designated as CuS/CuO/Cu-10, where "10" denotes sulfonation with Na 2 S for 10 min, showed the best photocatalytic properties, with MB degradation efficiencies under visible light irradiation of 87.4% after 20 min and 98.6% after 40 min. The enhanced photocatalytic activity can be attributed to effective electron–hole separation and improved visible light utilization due to the cooperative effect of the CuS/CuO heterostructures and conductive copper mesh. CuS/CuO nanowire heterostructures on Cu mesh have been fabricated through a two-step method of sulfonation and annealing. The formation of CuS/CuO nanowire heterostructures on Cu mesh obviously improves the visible light absorption of CuO/Cu and promotes the separation of photogenerated charge carriers. A sample designated as CuS/CuO/Cu-10 exhibited the best photocatalytic activity and stability in the degradation of Methylene Blue in the presence of H 2 O 2. Image 1 • CuS/CuO/Cu nanowire heterostructures have been fabricated by a sequence of sulfonation and annealing. • The formation of CuS/CuO heterostructures improves the photocatalytic activity of CuO/Cu. • The amount of CuS on a CuO surface affects the catalytic activity of CuS/CuO/Cu. [ABSTRACT FROM AUTHOR]