Reduction Of Cu Research Articles

Copper Versatility in Hydroxyapatite: Valence States, Clusters, and Optical Absorption Properties.

The solid-state reaction between a stoichiometric hydroxyapatite (HA) and CuO at temperatures above 1100 °C produces pure Cux-HA phases for x ≤ 0.7 with the general formula Ca10CuIx(PO4)6(OH)2-xOx. The Cu atoms are located at the center of the hexagonal tunnels between two hydroxyl ligands, as determined by Fourier analysis based on XRD data. During heat treatment, the reduction of Cu2+ ions into Cu+ is concomitant with the stabilization of copper in HA in the hexagonal tunnel. The incorporation of monovalent copper within the apatite, as revealed by XANES spectroscopy, explains the violet color of the samples. The incorporation of Cu+ ions, by substitution of a hydrogen atom by copper(I), results in the formation of linear O-Cu-O chains where the majority of which are isolated for x ≤ 0.3. In addition, the EXAFS investigation showed, thanks to the linear geometry of these clusters that results in multiple diffusion effects, the existence of [CuO]n chains with n ≥ 2, which only appear clearly for higher copper contents x ≥ 0.5. The strong covalency of the Cu-O bond in such a dumbbell configuration would lead to strong hybridization between the 3d and 4s orbitals of copper and the 2p orbitals of oxygen, as illustrated by ESR signals. In the case of Cu-doped HA prepared by coprecipitation and annealed at a lower temperature (T ≤ 600 °C), copper substitutes calcium according to the theoretical formula Ca10-xCux(PO4)6(OH)2, mainly at the Ca(2) site. This local environment is in line with the Jahn-Teller distortion induced by the Cu2+ ion (as evidenced by UV-vis-NIR, XPS, and XANES-EXAFS spectroscopy analyses) and also allows copper-copper interactions from one site to another, as observed by ESR spectroscopy. This versatility of copper in HA gives it optical properties that change from a violet color with near-IR absorption to a blue hue. In all cases, Cu-O-Cu interactions persist whatever the valence state, and heat treatment induces a redox phenomenon, with copper exchanging between two sites close to each other.

Tuning the Properties of Rigidified Acyclic DEDPA2- Derivatives for Application in PET Using Copper-64.

We present a detailed investigation of the coordination chemistry toward [natCu/64Cu]copper of a series of H2DEDPA derivatives (H2DEDPA = 6,6'-((ethane-1,2-diylbis(azanediyl))bis(methylene))dipicolinic acid) containing cyclohexyl (H2CHXDEDPA), cyclopentyl (H2CpDEDPA) or cyclobutyl (H2CBuDEDPA) spacers. Furthermore, we also developed a strategy that allowed the synthesis of a H2CBuDEDPA analogue containing an additional NHBoc group at the cyclobutyl ring, which can be used for conjugation to targeting units. The X-ray structures of the Cu(II) complexes evidence distorted octahedral coordination around the metal ion in all cases. Cyclic voltammetry experiments (0.15 M NaCl) evidence quasi-reversible reduction waves associated with the reduction of Cu(II) to Cu(I). The complexes show a high thermodynamic stability, with log KCuL values of 25.11(1), 22.18(1) and 20.19(1) for the complexes of CHXDEDPA2-, CpDEDPA2- and CBuDEDPA2-, respectively (25 °C, 1 M NaCl). Dissociation kinetics experiments reveal that both the spontaneous- and proton-assisted pathways operate at physiological pH. Quantitative labeling with 64CuCl2 was observed at 0.1 nmol for CHXDEDPA2- and CpDEDPA2-, 0.025 nmol for CBuDEDPA2- and 1 nmol for CBuDEDPA-NHBoc2-, with no significant differences observed at 15, 30, and 60 min. The radio-complexes are stable in PBS over a period of 24 h.

Self-catalytic enhancement of Cu-EDTA decomplexation and simultaneous Cu recovery via a dual-cathode electrochemical process

Heavy metals that are readily chelated with coexisting organic ligands in industrial wastewaters impose threats to environment and human health but are also valuable metal resources. Traditional treatment methods generally require additional chemicals and generate secondary contaminants. Here, a reagent-free dual-cathode electrochemical system was proposed for the efficient destruction of Cu-organic complexes and synchronous cathodic recovery of Cu, whereby in situ production of H2O2 at carbon aerogel (CA) cathode was coupled with the reduction of Cu(II) to Cu(I) and finally to Cu(0) at Ti cathode. The intermediate Cu(II) complexes enabled the self-reinforced degradation owing to their higher activities toward •OH generation by activating H2O2 in contrast to initial Cu-ethylenediaminetetraacetic acid (Cu-EDTA). The enhanced production of Cu(I) by Ti cathode facilitated both •OH and Cu(III) formation, and the copper redox cycle was realized in the self-reinforced system, maintaining its sustainable catalytic activity. The energy cost of the dual-cathode system is 0.011 kWh/g for decomplexation and 0.057 kWh/g for Cu recovery, which is much lower than single Ti or CA cathode system. This established process provides a prospective approach for cost-effective destruction of chelating metal complexes and metal resources recovery from heavy metal wastewaters.

Novel conjugated 5-pyridin-2-ylmethylidene 2-thio-4H-imidazol-4-ones and their complexes with copper(II) chloride

Three novel 2-thio-4H-imidazol-4-ones containing conjugated five, six- or seven-membered S,N-heterocycle and pyridin-2-ylmethylidene moiety (L) were synthesized by two-step reaction sequence starting from 2-thiohydantion. The ligand structures were confirmed by 1H NMR, 13C NMR and HRMS. The reactions of the ligands L with copper chloride dihydrate give the complexes of LCuCl2 composition. Copper coordination compounds with 6-(pyridin-2-ylmethylidene)-2,3-dihydroimidazo[2,1-b][1,3]thiazol-5(6H)-one (L1) and 2-(pyridin-2-ylmethylidene)-6,7-dihydro-5H-imidazo[2,1-b][1,3]thiazin-3(2H)-one (L2) were characterized by the X-ray data, demonstrating the distorted tetrahedral copper coordination environment. It was shown that the presence in the ligand L1 of a five-membered thiazolidine ring fused with imidazolone leads to a significant change in the geometric characteristics of the complex: an increase in the Cu-S distance and the flattening of copper coordination polyhedron. Both synthesized complexes were evaluated using cyclic voltammetry and demonstrated the quasi-reversible reduction of Cu(II) at ∼ −0.25 V. Testing of the antibacterial activity on the reporter strains E. coli ΔtolC pDualrep2 (AmpR) and E. coli lptDmut pDualrep2 (KanR) showed a lower activity of the synthesized copper-containing complexes compared to the complexes of similar ligand that did not have an additional condensed ring in its structure.

Synthesis of Composition-Tunable Ag-Cu Bimetallic Nanoparticles Through Plasma-Driven Solution Electrolysis.

Bimetallic nanomaterials have shown great potential across various fields of application. However, the synthesis of many bimetallic particles can be challenging due to the immiscibility of their constituent metals. In this study, we present a synthetic strategy to produce compositionally tunable silver-copper (Ag-Cu) bimetallic nanoparticles using plasma-driven liquid surface chemistry. By using a low-pressure nonthermal radiofrequency (RF) plasma that interacts with an Ag-Cu precursor solution at varying electrode distances, we identified that the reduction of Ag and Cu salts is governed by two "orthogonal" parameters. The reduction of Cu2+ is primarily influenced by plasma electrons, whereas UV photons play a key role in the reduction of Ag+. Consequently, by adjusting the electrode distance and the precursor ratios in the plasma-liquid system, we could control the composition of Ag-Cu bimetallic nanoparticles over a wide range.

Improved activation of malachite sulfurization flotation by thiourea's (CS(NH2)2): Performance and mechanism study

In this study, thiourea (CS(NH2)2) was an effective activator for promoting the sulfurization flotation of malachite. The flotation behavior of malachite in the presence of this activator was investigated. Experimental results revealed that thiourea is a superior activator for malachite sulfurization, achieving a recovery rate of over 89 % at appropriate dosages. Thiourea-sulfurized malachite forms a surface layer of copper(I) thiocyanate, which facilitates the reduction of Cu(II) to Cu(I) species, leading to the generation of more Cu(I)−S species. These species adsorb more readily onto the malachite surface compared to Cu(II)−S species. The robust layers consist of SCN¯ ligands that combine with copper(I) complexes to form CuSCN species during sulfurization. This enhances malachite surface sulfurization, resulting in higher flotation recovery. Further analysis using ToF−SIMS, FESEM−EDS, and XPS confirmed that thiourea likely chemisorbs onto the malachite surface through sulfurized malachite. The activation mechanisms and the presence of N-atoms in the XPS spectra verified that N−H, C−N, and Cu−N bonds were chemisorbed and formed on the surface, significantly improving the hydrophobicity of sulfurized malachite. This work has important implications for the future application of thiourea activation in flotation processes and could contribute to developing environmentally friendly solutions to meet consumer demand.

Enhanced hydrogen storage via microporous defects and Cu(I) sites in HKUST-1

A series of microporous defective HKUST-1 materials (DMT-HK-nF) are synthesized employing varying amounts (n = 10, 30, and 50 wt%) of 3,5-dinitrobenzoic acid (DNBA) and 1,3,5-benzene tricarboxylic acid as linkers. Subsequently, stepwise washing and solvent exchanges are conducted to enhance the density of Cu(I) sites and increases the surface area. DMT-HK-30F exhibits superior H2 storage capacity (2.55 wt% at 77 K, 100 kPa and 0.93 wt% at 298 K, 7 MPa), approximately 41% and 48% higher compared to pristine HKUST-1 (1.82 wt% at 77 K, 100 kPa, and 0.63 wt% at 298 K, 7 MPa), respectively. This improvement is attributed to an increase in Cu(I) sites and the introduction of linker defects. However, further addition of DNBA decreases the H2 storage capacity due to a reduction in Cu(I) sites and surface area caused by the formation of “missing metal cluster” defects. This study demonstrates that the simultaneous introduction of appropriate defects and high-density Cu(I) sites into the microporous structure is an effective strategy for enhancing the hydrogen storage performance of metal-organic frameworks.

Ag-modified CuO-Fe2O3 composite catalysts for low-temperature NH3-SCO

A series of CuFe and Ag-modified CuFe composite catalysts were prepared for low-temperature selective catalytic oxidation of ammonia (NH3-SCO). Significant synergistic effects existed between Cu and Fe oxides in the CuFe(7:12) catalyst for catalyzing NH3 oxidation. Loading 6 wt.% Ag over CuFe(7:12) further enhanced NH3 conversion and N2 selectivity. At 200 °C, NH3 conversion and N2 selectivity reached 97.1 % and 79.3 %, respectively, over 6Ag/CuFe(7:12). Besides the exceptional catalytic effects of Ag species, the increased surface area, formation of CuFe2O4, improved reducibility of Cu and Fe oxides, and increased acid sites due to the composite of Cu and Fe and modification with Ag contributed to the superior performance of the 6Ag/CuFe(7:12) catalyst in NH3-SCO. In-situ DRIFTS results showed that NH3 oxidation might follow the internal selective catalytic reduction mechanism: NH3 was dehydrogenated and oxidized to NOx and nitrate species, and the formed NOx and nitrate species were reduced by the remaining NH3, −NH2 and −NH species to N2 and H2O. Loading Ag over CuFe(7:12) suppressed the formation of NO and NO2 but promoted that of N2O during NH3 oxidation, which could be attributed to the enhanced formation and decomposition of NH4NO3 in the presence of Ag.

Degradation of citrate and reduction of Cu(II) in wastewater containing Cu(II)-citrate complex by UV irradiation

Advanced oxidation coupled with precipitation was employed to remove organic ligands (L) and Cu(II) from wastewater containing the Cu(II)-L complex. In this strategy, more than 99 % of Cu(II) and L were effectively removed. Cu(II) eventually entered the copper-containing sludge and cannot be recovered. In this study, the UV irradiation-induced degradation of citrate and simultaneous reduction of Cu(II) without any reagent was proposed. It was found that 97.34 % of citrate was degraded, simultaneously, 99.09% of Cu(II) were removed and recovered as high-purity Cu(0) (purity = 99.79%). The identification of free radicals and intermediates showed that the degradation of citrate was a successive decarboxylation process. H• and CO2•- formed during the successive decarboxylation and these two free radicals reduced Cu(II) to Cu(0). The pH values significantly affected the removal of citrate and Cu(II), and the optimal pH was 5.0 due to the strongest UV absorption by Cu(II)-citrate at pH 5.0. Dissolved O2, CO32– and PO43- slightly inhibited the citrate and Cu(II) removal, and Cl-, Ca2+ and Mg2+ exhibited negligible effects. This study provides a promising strategy for the degradation of citrate and simultaneous recovery of heavy metals from wastewater.

Projections of non-exhaust emissions from brake wear across Japan for 2020–2050

The concerns regarding the detrimental impacts of the increasing proportion of non-exhaust emissions are growing, even though there is a decrease in exhaust emissions from vehicles worldwide. Brake wear is a source of non-exhaust emissions. Despite the high density of traffic in Japan, the emission from brake wear has rarely been the target of studies. The objectives of this study are to estimate the environmental concentrations of copper (Cu) and antimony (Sb) released from brake wear in Japan and compare these concentrations on an annual basis (from 2020 to 2050). The Cu content in brake pads is estimated to decrease greatly from 2021 to 2025, whereas the Sb content is estimated to a moderate level by 2050. In this study, we used an atmospheric dispersion model to predict the reduction in Cu and Sb concentrations emitted from vehicles; owing to the transition to electric vehicles equipped with regenerative brakes (which will generate fewer wear particles), the Cu and Sb emissions in 2050 will decrease by 98 and 89 %, respectively, compared to the emissions noted in 2020. However, the contribution of conventional and electric vehicles to Cu and Sb concentrations will reverse in 30 years, owing to the country's goal that electric passenger vehicles will account for 100 % of the new-vehicle sales by 2035. By 2050, the contribution of conventional vehicles to Cu and Sb concentrations will be only 1 and 3 %, respectively, which will be from conventional vehicles supplied to the market by 2034. Thus, based on the future estimates of the number of vehicles and the composition of their brake pads, we predicted the environmental concentrations of Cu and Sb released from brake wear. The projections presented in this study can serve future interdisciplinary studies on environmental pollution, anthropological emissions reduction, and sustainable development.

Visible-light-driven Z-scheme ZnTe/WO3 heterojunction for simultaneous elimination of tetracycline and Cu(II)

Z-Scheme heterojunction photocatalysts can effectively suppress the recombination of charge carriers while maintaining high redox capacity. In this study, ZnTe/WO3 (ZW) Z-scheme heterojunction photocatalysts were synthesized using a hydrothermal method, and a series of photocatalytic materials were prepared for the simultaneous removal of tetracycline (TC) and Cu(II) from water. The physicochemical and photoelectrochemical properties of the catalytic materials were characterized through various methods, including SEM, XRD, XPS, and others. The experimental results indicate that the ZW-10 % composite material exhibits the most significant removal efficiency for pollutants. Within 150 min of visible light irradiation, the removal rates for TC and Cu(II) reach 73.8 % and 73.3 %, respectively, representing a substantial improvement compared to individual ZnTe and WO3. Free radical capture experiments and electron spin resonance analysis reveal that ·O2− and ·OH are the key reactive species responsible for TC oxidation, while electrons (e−) dominate the reduction of Cu(II).

CuOx supported LaCoO3 perovskite for the photoassisted reverse water gas shift reaction at low temperature

CuOx/LaCoO3 systems have been studied for the rWGS reaction under thermal assisted photocatalytic conditions within low temperature range of 180–330 ºC. CuOx species deposited from chemical reduction method over LaCoO3 homogeneously covered the perovskite surface. The reduction pretreatment before reaction leads to the partial Co reduction and the complete reduction of Cu. A significant improvement on CO production has been attained upon Cu incorporation. In addition, upon UV–vis irradiation the CO production is also enhanced. Best results have been obtained for 5 wt% Cu. The highest synergistic effect was observed for the lowest temperature, for which catalytic contribution is negligible. Thus, a good compromise is attained at 300 ºC for which a CO production of 5.45 mmol/h·g and 92 % selectivity, showing a good synergistic effect between thermo and thermo-photocatalytic activity.

Selective hydrogenation of biphenyl to cyclohexylbenzene over Cu based catalysts

The Cu/Al2O3, Cu/MgAlO, Cu/MgO and Cu-Ni/MgAlO catalysts (60 wt%) were studied for the selective hydrogenation of biphenyl (BP) to cyclohexylbenzene (CHB). The results showed the relatively high dispersion but low reducibility of Cu in the Cu/Al2O3. The acidic surface of Al2O3 caused the electron-deficient Cu that enhanced the adsorption of aromatic rings and thus led to the higher intrinsic activity for the hydrogenation of aromatic rings over the Cu/Al2O3, while the basic surface of MgO played the just opposite roles. The Cu/MgAlO possessed the suitable surface acidity and basicity and thus the high density of surface Cu active sites. Thus, it exhibited the higher overall activity than the Cu/Al2O3 and Cu/MgO for the hydrogenation of BP. However, the heats for the adsorption of toluene and H2 were significantly lower on Cu than those on Ni, which accounted for that the Ni was much more active than Cu for the hydrogenation of BP and CHB. Further studies showed that the activation energies for the hydrogenation of BP and CHB on Cu were high and differ greatly, resulting in the high conversion of BP with high selectivity to CHB over the Cu catalysts. On the other hand, the activation energies were significantly lower and did not differ so much on Ni, leading to the high conversion of BP and CHB for the formation of bicyclohexyl. Finally, the addition of a small amount of Ni (1 wt%) into the Cu/MgAlO greatly increased the conversion of BP under relative lower temperature while maintained the high selectivity to CHB.

Experimental and theoretical studies for instantaneous detection of l-cysteine and l-histidine using a simple Cu(II)-dppy complex

Developing simple and effective receptors for instantaneous detection of l-amino acids is vital for the recognition of life-threatening diseases in their early stage. Here, we report the synthesis and characterization of 2,6-di(pyrazin-2-yl)pyridine (dppy) based ligand L (L = 2,2′-(4-(3,4-diethoxyphenyl)pyridine-2,6-diyl)dipyrazine) and its copper (II) complex, [Cu(NO3)2L]. The in-situ prepared [Cu(H2O)2L](NO3)2 receptor in aqueous acetonitrile (4:1 v/v, 10 mM HEPES buffer, pH 7.4) medium displayed instantaneous responses towards biologically important bio-thiol l-Cysteine (Cys) and essential amino acid l-Histidine (His) over other l-amino acids through UV–Visible absorption spectral studies. Additionally, the competitive experiments confirmed that in-situ prepared [Cu(H2O)2L](NO3)2 receptor selectively detects Cys (1 equivalent) in the presence of other l-amino acids. The detection limits of Cys and His were calculated to be 8.23 × 10−7 M and 2.55 × 10−6 M, respectively. The density functional theory (DFT) calculation shows that selectivity of [Cu(H2O)2L](NO3)2 towards Cys is due to the reduction of Cu(II) to Cu(I) in the presence of Cys, while Cys is oxidized to cystine (Cys-Cys). For His, selectivity observed due to the formation of [Cu(His)2] moiety between Cu(II) ion with one His via N,O coordination mode and another His via N,N,O-coordination mode.

In situ fabrication of Cu2O array electrode for efficient detection of acetaminophen

In this paper, Cu(OH)2 nanosheet arrays were directly grown in an upright manner on the surface of copper foam (CF) through a simple solvent reaction, followed by the successful reduction of Cu(OH)2 into Cu2O using hydrazine hydrate vapor, resulting in a binder-free Cu2O@CF array electrode. The in situ growth technique guarantees robust bonding between Cu2O and the conductive substrate, thereby enhancing electron transfer among various electrode components. Additionally, the vertically aligned array structures facilitate rapid penetration and transfer of the analyte, while also allowing for thorough exposure of the electroactive surfaces to the electrolyte. When utilized as an adhesive-free biosensor, the obtained Cu2O@CF array electrode exhibited sensitive catalytic oxidation activity toward acetaminophen (AP), providing a wide linear range of 2–200 [Formula: see text]M and a low detection limit of 0.6 [Formula: see text]M for AP detection. Furthermore, the developed Cu2O@CF array electrode was successfully utilized to detect AP in medicine samples. With its simple fabrication method, broad linear range, low detection limit, and excellent stability, this electrode holds significant promise for the detection of AP in pharmaceuticals.

Copper-based nanoparticles supported on functionalized kaolinite for catalytic reduction of nitroaromatic compounds

A catalyst was synthesized by in situ reduction of Cu(II) ions on kaolinite particles. The clay mineral was modified by grafting propane sultone, to promote the stability of the catalyst and the good distribution of metal particles. Physicochemical characterizations revealed that the abundant synthesized metallic particles (mainly copper(I) oxide (Cu2O) although metallic copper particles were also present)) were of nanometric sizes. The catalyst was successfully applied for the catalytic reduction of three nitroaromatic compounds (4-nitrphenol, 4-chloronitroaniline, and 4-nitrocatechol). The variation of some experimental parameters was performed and marked effects on reaction rates were observed (increase with the catalyst concentration and decrease with the concentration of nitroaromatic compounds). An attempt to elucidate the mechanism of the catalytic reaction revealed that the adsorption of dihydrogen on the metal particles controlled the reaction rate while the adsorption of the nitroaromatic compounds controlled the induction time preceding the reduction reaction.

A CuSO4/Bicinchoninic acid/Reducing sugar based stable and non-ROS catalyst system for the CuAAC reaction in bioanalysis

The limitations of commonly used sodium ascorbate-based catalyst system for copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction include excess production of reactive oxygen species and rapid catalyst deactivation. In this study instead of using a highly active reducing agent, such as, sodium ascorbate, we chose reducing sugar as a mild reducing agent to build up the catalyst system for CuAAC reaction. Interestingly, the bicinchoninic acid (BCA) assay system containing reducing sugar satisfies the essential elements of the catalyst system for CuAAC reaction. We found that CuSO4/BCA/Reducing sugar system can catalyze the CuAAC reaction but with low yield. Rational analyses of various parameters in CuSO4/BCA/Glucose catalyst system suggested storage at room temperature might enhance the catalytic activity, which was proven to be the case. Importantly, the system remains stable at room temperature and minimal H2O2 was detected. Notably, our study showed that the coordination between the slow reduction of Cu(I) by reducing sugar and the selective chelation of Cu(I) by BCA is key to developing this system. The CuSO4/BCA/Reducing sugar catalyst system was successfully applied to various CuAAC reaction based bioanalyses, and it is suitable for the CuAAC reaction based bioanalyses that are sensitive to ROS or request long reaction time.

Efficient synthesis of 1,6-Hexanediol via the hydrogenation of dimethyl adipate on CuZn nanoparticles with balanced Cu+-Cu0 sites

In this paper, Cu-based catalyst was prepared by co-precipitation method with DMA hydrogenation as a probe reaction. Compared to the binary Cu-ZnO catalyst, the Cu-ZnO-MxOy (M=Ce, Ti, Zr and Al) catalyst modified with the addition of a third component showed a significant increase in 1,6-Hexanediol (HDO) selectivity. Especially, the dimethyl adipate (DMA) conversion, HDO selectivity and yield of the CZZ catalyst were up to 75.7 %, 53.6 % and 40.6 %, respectively, higher than others. Combining the results of XPS and N2O titration, HDO selectivity was adjusted by varying the Cu+/(Cu0+Cu+) ratio via the third component. The addition of ZrO2 prevented further reduction of Cu+ due to the formation of Cu/ZrO2 or Cu/ZnO species, thus maintaining a constant Cu+/(Cu0+Cu+) ratio and realizing the efficient selectivity of HDO. Furthermore, higher alkaline site density on the CZZ catalyst facilitated CO bond activation further favored the formation of 1,6-hexanediol. In addition, CZZ catalyst had better hydrogen dissociation capacity and smaller catalyst particle size, which will further promote the hydrogen dissociation and thus the hydrogenation process of DMA.

Mikania micrantha Kunth and its derived biochar impacts on heavy metal bioavailability and siderophore-related genes during chicken manure composting

Biochar can potentially reduce heavy metals (HMs) mobility and bioavailability during composting. However, siderophores secreted by functional microbes might lead to the re-mobilization of metals like Cu and Zn. Therefore, this study intended to explore the impacts of Mikania micrantha Kunth (MM) and MM-derived biochar (MMB) in the reduction of Cu and Zn bioavailability, and siderophore-related gene abundances during composting. Compared with MM and corn straw (CS) composts, a significant decline was noticed in the extractable and reducible Cu [(2.3 mg kg−1 + 12.1 mg kg−1), and (3.3 mg kg−1 + 14.6 mg kg−1)], and Zn [(103.1 mg kg−1 + 110.1 mg kg−1), and (109.6 mg kg−1 + 117.2 mg kg−1)] in MMB and corn straw biochar (CSB) composts, respectively. Besides, the lowest relative abundance of HMs-resistant bacteria particularly Corynebacterium (0.40%), Pseudomonas (0.46%), and Enterobacter (0.47%), was noted in MMB compost. Also, a significant increase in sesquiterpenoid and triterpenoid biosynthesis abundance (5.77%) accompanied by a reduction in the abundance of clusters related to siderophore transport, and siderophore transmembrane transporter activity was detected in MMB compost. Multivariate analysis labeled temperature, moisture content, total organic carbon, Corynebacterium, and Bacillus as the primary factors significantly correlated with the Cu and Zn bioavailability (− 0.90 ≤ r ≤ 0.90, P < 0.05). The structural equation model revealed that physicochemical parameters, microbial abundance, and siderophores exert a substantial influence on Cu and Zn bioavailability. Accordingly, MM and its derived biochar are recommended as an effective approach for accelerating Cu and Zn bioavailability reduction and managing the growth and distribution of invasive plants.Graphical

Click chemistry beyond metal-catalyzed cycloaddition as a remarkable tool for green chemical synthesis of antifungal medications.

Click chemistry is widely used for the efficient synthesis of 1,4-disubstituted-1,2,3-triazole, a well-known scaffold with widespread biological activity in the pharmaceutical sciences. In recent years, this magic ring has attracted the attention of scientists for its potential in designing and synthesizing new antifungal agents. Despite scientific and medical advances, fungal infections still account for more than 1.5 million deaths globally per year, especially in people with compromised immune function. This increasing trend is definitely related to a raise in the incidence of fungal infections and prevalence of antifungal drug resistance. In this condition, an urgent need for new alternative antifungals is undeniable. By focusing on the main aspects of reaction conditions in click chemistry, this review was conducted to classify antifungal 1,4-disubstituted-1,2,3-triazole hybrids based on their chemical structures and introduce the most effective triazole antifungal derivatives. It was notable that in all reactions studied, Cu(I) catalysts generated insitu by the reduction in Cu(II) salts or used copper(I) salts directly, as well as mixed solvents of t-BuOH/H2O and DMF/H2O had most application in the synthesis of triazole ring. The most effective antifungal activity was also observed in fluconazole analogs containing 1,2,3-triazole moiety and benzo-fused five/six-membered heterocyclic conjugates with a 1,2,3-triazole ring, even with better activity than fluconazole. The findings of structure-activity relationship and molecular docking of antifungal derivatives synthesized with copper-catalyzed azide-alkyne cycloaddition (CuAAC) could offer medicinal chemistry scientists valuable data on designing and synthesizing novel triazole antifungals with more potent biological activities in their future research.