Amount Of Cu Research Articles

Three-Level Nanoparticle Rocket Strategy for Colorectal Cancer Therapeutics in Photothermal Therapy, Inflammation Modulation, and Cuproptosis Induction.

Disturbances in intracellular copper (Cu) homeostasis can trigger cuproptosis, a new form of cell death, which, when combined with photothermal therapy (PTT), offers a promising solution to the persistent challenges in colorectal cancer (CRC) treatment. In this study, a "three-level nanoparticle rocket" strategy is developed by engineering Cu5.4O, a multifunctional Cu-based nanoenzyme that is photothermal and has electron transfer properties and antioxidant efficiency. Cu5.4O effectively remodels the inflammatory environment by scavenging reactive oxygen species, thereby overcoming the traditional limitations of PTT. Concurrently, Cu5.4O releases substantial amounts of Cu+ into malignant cells, disrupting Cu homeostasis, inducing cuproptosis, and ultimately inhibiting tumor progression. In vivo and in vitro experiments demonstrate that Cu5.4O operates through multiple successive and interlocking stages to significantly eradicate tumors, prevent relapse, and prolong survival. This study provides profound insights into the synergistic effects of PTT, inflammatory regulation, and cuproptosis within the complex tumor microenvironment, presenting innovative approaches for future CRC therapy.

Removal characteristics for nine species of per-and poly-fluoroalkyl substances(PFAS) using diffrerent types of anion exchange(AIX)

Objectives : This study aims to compare the removal characteristics of nine PFAS species using two commercial anion exchanges(AIXs) with different matrices and their Cu-modified derivatives.Methods : IRA900-Cu and A860-Cu were synthesized from two commercial AIXs(IRA900 and A860) using a 1% CuCl2·2H2O solution. SEM-EDS analysis and Cu2+ extraction experiments were conducted to evaluate surface characteristics under different matrices and their modification. Batch removal tests, pH effect tests ranging from 4 to 8.5, and isotherm tests(Langmuir and Freundlich) were performed.Results and Discussion : According to SEM-EDS analysis, the (O+N)/C ratio for A860(polyacrylic) was found to be 2.57 times higher than that of IRA900(polystyrene), indicating A860 is more hydrophilic than IRA900. In addition, no significant changes in surface properties, including Cu and Cl elements, were observed after modification. The total uptake of the nine PFAS species by IRA900 was 2.21 times higher than that of A860, due to the greater hydrophobicity of IRA900. The effect of Cu modification on both AIXs was not significant due to the low amount of Cu on the surface, except for the short-chain species(PFBA and PFPeA) in IRA900. While the total uptake was not influenced by pH in IRA900 and IRA900-Cu, it decreased rapidly in A860 at pH 7.0 and 8.5, likely due to its relatively low basicity and hydrophilic matrix. Based on Langmuir and Freundlich isotherm models, the total uptake and KF for IRA900 were 2.97 and 16.7 times higher than those of A860, respectively. Comparing the uptake for each species, higher capacity was generally observed for sulfonic functional groups(PFSA) than for carboxylic functional groups (PFCA) at the same chain length, and the capacity increased with increasing chain length.Conclusion : Higher hydrophobicity of IRA900 plays a key role in PFAS adsorption, regardless of the species, and is less sensitive to basic solution conditions.

Syngas Production Improvement from CO2RR Using Cu-Sn Electrodeposited Catalysts.

Electrochemical reduction of CO2 is an efficient and novel strategy to reduce the amount of this greenhouse-effect pollutant gas in the atmosphere while synthesizing value-added products, all of it with an easy synergy with intermittent renewable energies. This study investigates the influence of different ways of combining electrodeposited Cu and Sn as metallic elements in the electrocatalyst. From there, the use of Sn alone or with a small amount of Cu beneath is investigated, and finally, the best catalyst obtained, which has Sn over a slight Cu layer, is evaluated in consecutive cycles to make an initial exploration of the catalyst durability. As a result of this work, after optimization of the Sn and Cu-based catalysts, it is possible to obtain more than 60% of the organic products of interest, predominantly CO, the main component of syngas. Finally, this great amount of CO is obtained under low cell potential (below 3 V), which is a remarkable result in terms of the cost of the process.

Surface Oxygen Vacancies on Copper-Doped Titanium Dioxide for Photocatalytic Nitrate-to-Ammonia Reduction.

Photocatalytic transformation of nitrate (NO3-) in wastewater into ammonia (NH3) is a challenge in the detoxification and recycling of limited nitrogen resources. In particular, previously reported photocatalysts cannot promote the reaction using water as an electron donor. Herein, we report that copper-doped titanium dioxide (Cu-TiO2) powders, prepared via the sol-gel method and subsequent calcination, promote NO3--to-NH3 reduction in water. The Cu2+ doping into TiO2 creates a large number of surface oxygen vacancies (OVsurf), which are stable even under aerated conditions. The Ti3+ and Cu2+ atoms adjacent to OVsurf behave as active sites for the NO3--to-NH3 reduction. Doping with an appropriate amount of Cu2+ and calcination at an appropriate temperature produce the catalysts with a large number of OVsurf, while maintaining a high conductivity, and exhibit a high photocatalytic activity.

Incorporation and Compensatory Doping Processes of Cu into ZnO Nanowires Investigated at the Local Scale

The Cu compensatory doping of ZnO nanowires is of great interest to face the challenge arising from the detrimental screening of the piezoelectric potential generated under mechanical solicitations. However, the incorporation processes of Cu into ZnO nanowires are largely unknown. Here, they are investigated locally by combining mass spectrometry and optical spectroscopy with X‐Ray linear dichroism using synchrotron radiation. By varying the Cu(NO3)2/Zn(NO3)2 concentration ratio from 0 to 10% in a chemical bath kept at high pH, it is shown that the amount of Cu incorporated into ZnO nanowires varies from around 4.5 × 1016 to 3.6 × 1018 at cm−3. However, only 15% of the incorporated Cu forms CuZn‐related defects, while the remaining Cu lies on the surfaces of ZnO nanowires. Importantly, thermal annealing under O2 atmosphere is found to electrically activate the incorporated Cu, resulting in the formation of CuZn‐related defect complexes involving nearby VZn, the structured green emission band with a strong phonon coupling, and the increase in the electrical resistivity. These findings shed light on the local environment of Cu incorporated into ZnO nanowires and the required conditions for electrically activating the compensatory doping, as an important outcome for enhanced piezoelectric nanogenerators and stress/strain sensors.

Construction of Mo2TiC2Tx MXene as a Superior Carrier to Support Ru-CuO Heterojunctions for Improving Alkaline Hydrogen Oxidation.

The sluggish anodic hydrogen oxidation reaction (HOR) of the hydroxide exchange membrane fuel cell (HEMFC) is a significant barrier for practical implementation. Herein, we designed a catalyst of Mo2TiC2Tx MXene-supported Ru-CuO heterojunctions (named as Ru-CuO/MXene). The XPS spectra and the d-band center data of the different amounts of Cu of the Ru-CuO/MXene suggested that there existed a strongly electronic metal-support interaction between the active species and the substrate with MXene as the excellent carrier. Furthermore, the in situ electrochemical experimental results (operando electrochemical impedance spectroscopy and in situ electrochemical Raman spectroscopy) and density functional theory (DFT) calculations showed that Ru and CuO were the optimal adsorption sites for surface species *H and *OH, respectively, endowing Ru-CuO/MXene with the ability to weaken the hydrogen binding energy (HBE) and strengthen the hydroxide binding energy (OHBE). Remarkably, the optimized catalyst modified an impressive HOR activity in the 0.1 M KOH electrolyte with a kinetic and an exchange current density of 7.63 and 1.37 mA cm-2 at 50 mV overpotential (vs. RHE), respectively, which were 1.98- and 1.2-fold higher than those of commercial Pt/C (20 wt %). Finally, the as-prepared catalyst also exhibited superior durability and exceptional CO antipoisoning ability in 1000 ppm of the CO/H2-saturated 0.1 M KOH electrolyte. This work provides an inspiring strategy to design high-activity HOR electrocatalyst-based metallic Ru in alkaline environments.

Regioselective Reversal in One-Pot and Two-Step Reaction of 1-(2-Hydroxyphenyl)-Propargyl Alcohols with Aryl/Alkyl Mercaptan: Construction of 3-(Alkylthio)benzofurans and 2-(Alkylthiomethyl)benzofurans Starting from Identical Materials.

The Cu(MeCN)4PF6-catalyzed reaction of 1-(2-hydroxyphenyl)-propargyl alcohols with aryl/alkyl mercaptan and subsequent treatment with K2CO3 only offered 3-(alkylthio)benzofurans, whereas the stoichiometric-exceeding CuI-mediated reaction and subsequent treatment with DIPEA furnished 2-(alkylthiomethyl)benzofurans with high selectivity. The amount of Cu(I) salts plays a key role in selective formation. This unique protocol for the selective construction of the two series of benzofurans containing alkylthio group proved to be suitable for broad substrates 1 and 2 except for aliphatic alkynyl alcohols.

Lattice plainification and band engineering lead to high thermoelectric cooling and power generation in n-type Bi2Te3 with mass production.

Thermoelectrics can mutually convert between thermal and electrical energy, ensuring its utilization in both power generation and solid-state cooling. Bi2Te3 exhibits promising room-temperature performance, making it the sole commercially available thermoelectrics to date. Guided by the lattice plainification strategy, we introduce trace amounts of Cu into n-type Bi2(Te, Se)3 (BTS) to occupy Bi vacancies, thereby simultaneously weakening defect scattering and modulating the electronic bands. Meanwhile, the interstitial Cu can bond with the BTS matrix to form extra electron transport pathways. The multiple occupations of Cu substantially boost carrier mobility and electrical performance. Consequently, the BTS+0.2%Cu achieves a room-temperature ZT of ∼1.3 with an average ZT ave of ∼1.2 at 300-523K. Moreover, the kilogram-scale ingot designed for mass production also exhibits high uniformity. Finally, we fabricate a full-scale device that achieves an excellent conversion efficiency of ∼6.4% and a high cooling ΔT max of ∼70.1K, both of which outperform commercial devices.

Electrodeposition of Extremely Cu-Rich CuPd Bimetallic Nanoparticles from an Amide-Type Hydrophobic Protic Ionic Liquid

Cupric oxide (CuO) and palladium(II) acetate (Pd(Ac)2) were dissolved into the amide-type hydrophobic protic ionic liquid (IL), protonated-betaine bis((trifluoromethyl)sulfonyl)amide ([Hbet][TFSA]), to produce the Cu(II) and Pd(II) species for the electrodeposition of metallic Cu, Pd, and CuPd nanoparticles (NPs). Unlike the electrodeposition conducted in common aqueous electrolytes containing the equivalent amounts of Cu and Pd ions, Cu-rich rather than Pd-rich CuPd co-deposits were obtained from the IL [Hbet][TFSA]; which might result from the retardation of Pd deposition on preferentially electrodeposited Cu surface or the formation of a new metal species when both metal ions co-existed in the IL, leading to an uncommon large overpotential needed to reduce the species into Pd metal. The surface morphologies of CuPd NPs significantly relied on their elemental compositions that could be controlled by the concentration of Pd(II) and/or the applied electrodeposition potential. CuPd NPs with different Pd contents showed very different responses in the reaction current of nitrate reduction. Nevertheless, the CuPd NPs regardless of the Pd contents showed advantages over the Cu nanoparticles in the electrochemical reduction of nitrate, which might be due to the synergistic effects between the Cu and Pd atoms.

Cu-induced interface engineering of NiCu/Ni3N heterostructures for enhanced alkaline hydrogen oxidation reaction

Constructing well-defined interfaces in catalysts is a highly effective method to accelerate reactions with multiple intermediates. In this study, we developed a heterostructure catalyst combining fcc NiCu and hcp Ni3N, aiming at achieving superior performance in alkaline hydrogen electrocatalysis. The NiCu/Ni3N not only overcomes the inadequate hydroxyl binding energy performance of NiCu alloys but also solves the problems of insufficient active sites found in most Ni/Ni3N. Experimental results and density functional theoretical calculations reveal that the formation of heterostructure significantly depends on the amount of Cu. This approach effectively prevents the side effects of increased catalyst particle size, typically resulting from the high temperatures and prolonged reaction times required for conventional synthesis of Ni/Ni3N. The interface of this heterostructure induces a distinctive overlapping effect that enhances the adsorption of water and lowers the energy barrier for the rate-determining step. The NiCu/Ni3N catalyst shows an impressive activity of 71.8 mA mg−1 at an overpotential of 50 mV, a 14.7 times efficiency enhancement compared to pure Ni and comparable to that of low-loaded commercial Pt/C. This research highlights the potential of NiCu/Ni3N in advancing catalyst development.

Evaluation of Performance and Longevity of Ti-Cu Dry Electrodes: Degradation Analysis Using Anodic Stripping Voltammetry.

This study aimed to investigate the degradation of dry biopotential electrodes using the anodic stripping voltammetry (ASV) technique. The electrodes were based on Ti-Cu thin films deposited on different polymeric substrates (polyurethane, polylactic acid, and cellulose) by Direct Current (DC) magnetron sputtering. TiCu0.34 thin films (chemical composition of 25.4 at.% Cu and 74.6 at.% Ti) were prepared by sputtering a composite Ti target. For comparison purposes, a Cu-pure thin film was prepared under the same conditions and used as a reference. Both films exhibited dense microstructures with differences in surface topography and crystalline structure. The degradation process involved immersing TiCu0.34 and Cu-pure thin films in artificial sweat (prepared following the ISO standard 3160-2) for different durations (1 h, 4 h, 24 h, 168 h, and 240 h). ASV was the technique selected to quantify the amount of Cu(II) released by the electrodes immersed in the sweat solution. The optimal analysis conditions were set for 120 s and -1.0 V for time deposition and potential deposition, respectively, with a quantification limit of 0.050 ppm and a detection limit of 0.016 ppm. The results showed that TiCu0.34 electrodes on polyurethane substrates were significantly more reliable over time compared to Cu-pure electrodes. After 240 h of immersion, the TiCu0.34 electrodes released a maximum of 0.06 ppm Cu, while Cu-pure electrodes released 16 ppm. The results showed the significant impact of the substrate on the electrode's longevity, with cellulose bases performing poorly. TiCu0.34 thin films on cellulose released 1.15 µg/cm2 of copper after 240 h, compared to 1.12 mg/cm2 from Cu-pure films deposited on the same substrate. Optical microscopy revealed that electrodes based on polylactic acid substrates were more prone to corrosion over time, whereas TiCu thin-film metallic glass-like structures on PU substrates showed extended lifespan. This study underscored the importance of assessing the degradation of dry biopotential electrodes for e-health applications, contributing to developing more durable and reliable sensing devices. While the study simulated real-world conditions using artificial sweat, it did not involve in vivo measurements.

Temperature-Robust Short-Term Memory Stored at Electrode/Ionic Liquid Interface and Its Applications for Energy-Efficient Information Processing

Electrochemical reactions (ERs) accompanied by electrodeposition at electrode/ionic liquid (IL) interface have been adopted to various application such as batteries [1] and metal plating for interconnects [2]. Herein, we demonstrate that the electrode/IL interface can be used for the physical device implementation of the advanced machine learning (ML) model called reservoir computing (RC), which is an edge AI computing-friendly ML model. In this application, the electrode/IL interface extracts the feature from the input data by converting the signal waveform via ER at the interface [3-5]. Our device having the functional electrode/IL interface is called “ionic liquid-based physical reservoir device (IL-PRD)”.Fig. 1(a) is an optical microscope image of the IL-PRD having Pt electrodes, where ERs occur. The external area of the white dotted line in Fig. 1(a) is covered by SiO2. Fig. 1(b) explains the data processing flow. We performed a benchmark task for ML called a short-term-memory (STM) task. The input signal u(TS) at the time step TS is a random time-series of the binary data (0 or 1), where the signals “0” and “1” are input to the IL-PRD as the triangular voltage pulses (TVPs) with the pulse height/width of -3.0 V/500 ms and +3.0 V/500 ms, respectively. By using the output current signal from the IL-PRD, the efficient ML in a simple neural network (NN) can be conducted. In the STM task, the target data of the ML is u(TS-TS delay), where TS delay was a delay time. The ML performance is evaluated by a memory capacity (MC), which was calculated by adding the square of the correlation coefficient between the target data and model output. A linear regression (LR) model was used after increasing the input variable (x i) for LR by a virtual node method [6]. The weight value w i (fitting parameters of LR) was optimized to minimize the least-square error. In the present study, we investigated the temperature dependence of MC using two different ILs, which were 1-Butyl-3-methylimidazolium Bis(trifluoromethanesulfonyl)imide ([C4mim][Tf2N]) containing Cu cations with the concentration C Cu of 0.1 mol/L and 0.4 mol/L. The ML at the moderately elevated temperature is indispensable when considering the high-temperature application such as the life-time prediction of batteries operated at high temperature [1] as well as the signal processing in the highly integrated circuits [7], which is quite thermogenetic.Fig. 2 is an example of the current-voltage (I-V) curves plotted using the randomly input TVPs and corresponding current obtained at 26 ºC using the IL-PRD with C Cu = 0.1 mol/L. The color-coding of the I-V curves in Fig. 2 was conducted according to the input signal history over three time steps. For instance, the figure legend of “001” shown in Fig. 2 indicates that the corresponding current data was obtained when “1” was input after “0” was input two times. As shown in Fig. 2, the shapes of the I-V curve differ depending on the input signal history, indicating that the output signal from the IL-PRD successfully extracted the feature of the input signal history, in other words, the memory about the time series input signal. The values of MC for IL-PRD with C Cu = 0.1 mol/L and 0.4 mol/L are plotted in Fig. 3 as a function of temperature. Compared with the case of C Cu = 0.4 mol/L, the IL-PRD with C Cu = 0.1 mol/L exhibited the better robustness against the temperature change. In our previous study [4], Cu and some Cu compounds are formed by the electrodeposition during the device operation, and Cu is especially soluble in the present IL even if no external voltage is applied. Such Cu dissolution is reasonably considered to be accelerated by the temperature rise. In the IL-PRD with C Cu = 0.1 mol/L, less amount of Cu is intrinsically involved in ERs at the Pt/IL interface compared to that with C Cu = 0.4 mol/L. Consequently, the electrical properties of the IL-PRD with C Cu = 0.1 mol/L and the consequent ML performance became more stable against the temperature change, which is preferred for the RC under temperature change.

Microwave-Assisted synthesis of CuxFe100-x/Carbon aerogel (x = 0, 30, 50, 70) with enhanced Electrocatalytic activity towards oxygen evolution reaction

A simple and efficient microwave-assisted synthesis route was adopted for carbon aerogel (CA)-supported Cu and Fe catalysts for OER in alkaline media. Catalysts were characterized physically by ICP-MS, XRD, TEM, XPS, SEM, and EDX and electrochemically by CV, chronoamperometry, and EIS. The catalyst having the composition of Cu30Fe70/CA showed excellent activity towards OER with low overpotential (345 mV) and Tafel slope (92.5 mV dec−1). Diffusion coefficient (D° = 2.1 × 10−8 cm2 s−1), mass transport coefficient (mT = 2.8 × 10−4 cm s−1), heterogeneous rate constant (k° = 5.7 × 10−4 cm s−1), and electrochemically active surface area (0.0167 cm2) were obtained for Cu30Fe70/CA modified glassy carbon electrode. CV response in the non-faradic region showed that Cdl and electrochemical surface area (ECSA) of Cu30Fe70/CA increased ∼ 34 times compared to Fe/CA. This work suggests that adding up an optimum amount of Cu to the Fe/CA nanocomposite offers a cost-effective and efficient electrocatalyst for OER.

Mushroom production on digestate: Mineral composition of cultivation compost, mushrooms, spent mushroom compost and spent casing

Produced in the process of anaerobic digestion, the effluent called digestate is rich in nutrients and can be used as a growing media for mushrooms. However, it can also be rich in non-essential and trace elements, heavy metals, various organic pollutants, pharmaceuticals, and other unwanted compounds with potential negative effects. Therefore, two button mushroom species, Agaricus bisporus (brown cultivar) and Agaricus subrufescens, were cultivated on digestate based substrate. The mineral composition of the experimental mushroom compost (EMC), mushrooms (M), spent mushroom compost (SMC) and spent casing (SC) was evaluated by means of ICP OES. Mineral distribution and quantity were substrate dependent, digestate origin was determined for most of investigated elements, excluding Ca, Mo, Pb, Ce and Nd, where the source was straw. However, content of elements with high mobility such as Cd, Cu, Pb and Zn for EMC was low. Short composting method for mushroom compost preparation used in this study could be suitable method for reducing available Cd, Cr, Ni, Pb, Zn and total As. For the casing material, bark was richer in major essential elements (MEE's) and essential trace elements (ETE's), besides Ca, where peat indicated higher content (1490 mg kg-1). From the trace elements with detrimental health effects (TEWDHE) group, bark was richer in Ba and Pb, but peat contained significant content of As (3.92 mg kg-1). The results clearly indicated both the studied mushrooms are valuable source of K, Na and Se, while A. subrufescens provided higher amounts of Cu and Zn. No threat for human consumption for Ni, Pb, As, and Cd, their content is under the limits and decreases with each subsequent mushroom yield. SMC and SC were nutrient rich especially for Fe, Mg, Mn, Si and Zn, giving them added value as biobased product for boosting vegetable crop yield. However, Cr and Ni, ETS's for plants in lower amounts, were elevated in SMC/SC, therefore the mineral composition should be monitored. Low concentration of hazardous elements in the spent substrates allows for subsequent use.

Endogenous Cu(II) Labeling for Distance Measurements on Proteins by EPR.

In-cell measurements of the relationship between structure and dynamics to protein function is at the forefront of biophysics. Recently, developments in EPR methodology have demonstrated the sensitivity and power of this method to measure structural constraints in-cell. However, the need to spin label proteins ex-situ or use noncanonical amino acids to achieve endogenous labeling remains a bottleneck. In this work we expand the methodology to endogenously spin label proteins with Cu(II) spin labels and describe how to assess in-cell spin labeling. We quantify the amount of Cu(II)-NTA in cells, assess spin labeling, and account for orientational effects during distance measurements. We compare the efficacy of using heat-shock and hypotonic swelling to deliver spin label, showing that hypotonic swelling is a facile and reproducible method to efficiently deliver Cu(II)-NTA into E. coli. Notably, over six repeats we accomplish a bulk average of 57 μM spin labeled sites, surpassing existing endogenous labeling methods. The results of this work open the door for endogenous spin labeling that is easily accessible to the broader biophysical community.

The disorder-order transition of FeCuPt nanoparticles with various Cu content

The effect of adding a third-element on disorder-order transition of FePt has been demonstrated using FeCuPt alloy as a model. The introduction of Cu leads to an increase in the ordering degree, and a moderate amount of Cu enhancing the most. Density Functional Theory calculations indicate that the disorder-order transition in FePt is influenced by the ordering temperature and vacancy formation energy. FePtCu alloy with a moderate Cu content exhibits the lowest vacancy formation energy in the L10-phase, which promotes the atom diffusion during annealing and resulting in a higher ordering degree. This study summarizes the annealing temperature, time, and thermodynamic or kinetic conditions required to achieve L10-FePtX alloy with superior ordering degrees. The findings offer valuable insights for selecting suitable third-elements and annealing parameters to produce L10-FePtX alloy with enhanced ordering degrees.

Highly enhanced photocatalytic performance for CO2 reduction on NH2-MIL-125(Ti): The impact of (Cu, Mn) co-incorporation

Photocatalytic CO2 reduction has been considered as an efficient way for the carbon nuetrality. In this work, a series of (Cu, Mn) co-incorporated metal-orgnaic frameworks (MOFs) (NH2-MIL-125(Ti) (NML)) with different Cu2+/Ti4+ and Mn2+/Ti4+ molar ratios are systematically investigated to improve the efficiency for photocatalytic CO2 reduction. The optimized sample (1 M−5C−−NML) shows a highest yield of HCOOH (116.74 μmol.g−1.h−1) (3.71 times higher than that of NML), and a superior apparent quantum efficiency (AQE) (6.74 % at 405 nm). The improved performance is attributed to the formed oxygen vacancy and intermediate energy level as introduced by the co-incorporation, which facilitate the charge separation and enhance the visible-light-harvesting of NML. It shows that the density of oxygen vacancies increases with the increasing amount of Cu, resulting in enhanced charge separation. However, the increasing amount of Mn leads to the short-range Mn-Mn interaction, the concentration quenching effect as well as the inhibited photocatalytic performance. This work shows that the co-incorporated MOFs can be used as an advanced photocatalyst.

The effects of calcination temperature and dispersants on the catalytic performance of Co0.8Cu0.2/CNC for the hydrolysis of ammonia borane to hydrogen

Ammonia borane (NH3BH3, AB) is considered as an ideal hydrogen storage material for portable hydrogen production. In this paper, a bimetallic carbon cube (Co0.8Cu0.2/CNC) catalyst was prepared by high-temperature calcination of the Co0.8Cu0.2-ZIF precursor, which was obtained by stirring the reactants at room temperature. In addition, the microstructure and composition of the catalyst were investigated using various characterization methods. The change regularity of the catalyst was explored through the single-variable method. The results showed that the addition of a small amount of Cu had a stabilizing effect on the cubic morphology of the Co0.8Cu0.2/CNC catalyst. When the dispersant was CTAB and the calcination temperature was 873 K, the activation energy (Ea) for catalyzing the hydrolysis of AB to hydrogen was 50.79 kJ/mol with the transition frequency (TOF) value as high as 23.37 min–1. Moreover, the catalyst could still catalyze the complete hydrolysis of AB to hydrogen after 25 cycles, which indicated that the catalyst had good stability performance.

Enhanced Cu-EDTA degradation with trace Cu(II) in limestone via activating PMS

Effective removal of heavy metal complexes from contaminated water remains a challenging task. In this work, a limestone/PMS system was constructed for the efficient degradation of Cu-EDTA. Under the conditions of 3.0 g/L limestone and 1.0 mM PMS, the degradation efficiency of 10.0 mg/L Cu-EDTA reached 99.0 % in 60 min, and the removal efficiency of Cu ions approached 50.0 %. The main active specie revealed by quenching and EPR experiments was the singlet oxygen (1O2). Interestingly, Trace amounts of Cu(II) in limestone react with PMS enhancing the degradation of Cu-EDTA. The results of the HPLC-MS analysis showed that the reactive species attacked the Cu–O and Cu–N bonds, as well as triggered a decarboxylation process, resulting in the decomposition of Cu-EDTA into six intermediates. Meanwhile, SEM and XPS analyses revealed that Cu ions released during the degradation of Cu-EDTA are deposited on the limestone surface as Cu(OH)2 and Cu2(OH)2CO3. In addition, the initial pH and co-existing ions have a weak effect on the system. Finally, a one-month continuous flow experiment showed that the degradation efficiency of Cu-EDTA was about 95.0 % and the removal efficiency of Cu ions was 40.0 %. In conclusion, this study provides a new approach for the destruction of metal complexes and the removal of heavy metals.

Effects of Soil Properties on the Accumulation and Bioavailability of Copper in the Orange Growing Soil in Cao Phong, Hoa Binh

This study focuses on investigating the crucial influence of some soil properties on the adsorption capacity and fractions of Cu in the citrus-growing soil in Cao Phong district, Hoa Binh province. Batch experiments were conducted by adding 0, 100, 500, and 1000 mgCu/L to soil samples with different characteristics. In the 100 mgCu/L added experiment, we found the highest Cu adsorption rate (> 93.76%) in soil samples with loamy texture, high pHKCl, %OC, and low nutrients. Conversely, the lowest Cu adsorption rates (78.32-79.23%) were observed in soil samples with lower pH, and higher %OC and nutrient availability. Noting that the total adsorbed Cu has a negative correlation with the amount of Cu added to the soil, gradually decreasing from (78.32-95.67%) to (26.67-34.19%) and the lowest (22.48-28.56%) in soil samples with the added levels of 100, 500, and 1000 mgCu/L, respectively. In soil samples with total Cu > 200 mg/kg, pHKCl 4.79-5.32, and OC 1.34-2.06%, the bioavailable Cu ranged from 2.29-4.29 mg/kg, which is safe for the soil environment and ecosystem, and sufficient as a micronutrient for citrus plants. It is necessary to find the best solutions for managing Cu-polluted soils.