Acid Tetrasodium Salt Research Articles

An environmentally friendly depressant for magnesite and calcite flotation separation: Selective depression and adsorption mechanism

The similar crystal structures and chemical properties of magnesite and calcite make their effective separation through flotation challenging. This study explores the use of Glutamic acid diacetic acid tetrasodium salt (GLDA), a novel environmentally friendly chelating reagent, to enhance the flotation separation of magnesite and calcite. Flotation test results indicate that in a sodium oleate (NaOL) system, GLDA selectively inhibits the flotation of calcite. Under optimal conditions (slurry pH=9.20, GLDA 15 mg/L, and NaOL 140 mg/L), a flotation concentrate with an MgO grade of 46.21 %, CaO grade of 1.39 %, and an MgO recovery rate of 73.17 % was achieved. GLDA minimally affects the hydrophobicity of magnesite but significantly reduces the hydrophobicity of calcite. The selective inhibition mechanism of GLDA was investigated using zeta potential measurements, FTIR, and XPS analyses. Results show that GLDA selectively reacts with Ca sites on the calcite surface, adsorbing and covering it, thereby preventing NaOL from adsorbing on the calcite. Conversely, GLDA has a minor impact on the Mg sites on the magnesite surface, resulting in a negligible effect on NaOL adsorption by magnesite. Consequently, GLDA enhances the flotation separation efficiency of magnesite and calcite. The research results have potential for application in the purification of low-grade magnesite ore.

1, 3, 6, 8-pyrene sulfonic acid tetrasodium fluorescent pigment synthesis and security ink production

Colorants used in security inks are special pigments that radiate in the UV region or IR region. Obtained pigments can be from valuable rare earth elements or they can be organic based. Organic-based pigments are generally insoluble in water, which limits their use. For this purpose, an organic-based UV-radiating pigment was synthesized and made water-soluble by forming its salt. With the obtained salt-formed pigment, inkjet ink that can be used in counterfeiting was applied and its printability and resistance properties were determined. In this study, 1, 3, 6, 8-pyrene sulfonic acid tetrasodium salt was synthesized and water-based inkjet inks with hydroxy ethyl cellulose binder were produced. The prepared inks were printed on the paper surface. The color and gloss of the prints obtained were measured both in the visible region and in the UV region. Its optical properties were detected by UV spectroscopy. Strength properties such as light fastness, nitro resistance, alkali resistance, acid resistance, rub resistance, drying time, adhesion and dry film weight of the prints were determined. As a result; Inkjet ink with 1, 3, 6, 8-pyrene sulfonic acid tetrasodium salt was produced and it was concluded that it has good resistance properties.

Adsorption of spray droplets reduced adsorption of dicamba spray droplets on leaves as droplet size increases

Abstract Off-target movement of growth regulator herbicides can cause severe injury to susceptible plants. Apart from not spraying on windy days or at excessive boom heights, making herbicide applications using nozzles that produce large droplets is the preferred method for reducing herbicide drift. Although large droplets maintain a higher velocity and are more likely to reach the leaf surface in windy conditions, their ability to remain on the leaf surface is poorly understood. Upon impact with the leaf surface, droplets may shatter, bounce, roll-off, or be retained on a leaf surface. We examined how different nozzles, pressures, and adjuvants impact spray droplet adsorption on the leaf surface of common lambsquarters and soybean. Plants were grown in a greenhouse and sprayed in a spray chamber. Three nozzles (XR, AIXR, and TTI) were evaluated at 138, 259, and 379 kPa. Dicamba (0.14 kg ae ha⁻¹) was applied alone and with methylated seed oil (MSO), a non-ionic surfactant, silicone-based adjuvant, crop oil concentrate, or a drift reduction adjuvant. A 1, 3, 6, 8-pyrene tetra sulfonic acid tetra sodium salt was added as a tracer. Dicamba spray droplet adsorption when using the XR nozzle, which produced the smallest spray droplets, was 1.75 times greater than when applied with the TTI nozzle with the largest spray droplets. Applying dicamba with MSO increased adsorption on leaf surfaces nearly four times the amount achieved without an adjuvant. The lowest application pressure (138 kPa) increased dicamba spray volume adsorbed more than 10% compared to the higher pressures 259 and 379 kPa. By understanding the impacts of these application parameters on dicamba spray droplet adsorption, applicators can select application parameters, equipment, and adjuvants that will maximize the amount of dicamba spray volume retained on the target leaf surface while minimizing dicamba spray drift.

Analysis of the optical and electronic characteristics of Al/NiPc complex/p-Si diode

The primary goal of this work is to explore how the introduction of the Nickel (II) phthalocyanine tetrasulfonic acid tetrasodium salt (NiTsPc) organic interlayer influences the performance of conventional metal/semiconductor diodes. Firstly, the optical features of the NiTsPc organic film formed onto glass substrate were investigated. For this, the UV–vis spectroscopic data were used to determine various optical parameters like absorption coefficient (α), extinction coefficient (k), and refractive index (n). Then, Al/NiTsPc/p-Si diode was produced by forming ohmic and rectifier contact. The current–voltage (I-V) measurements were analyzed taking into account thermionic emission (TE) approach at room temperature. Device parameters such as ideality factor (η), barrier height (Φb), and resistance were investigated with the help of I-V technique. The Al/p-Si structure containing NiTsPc film showed good rectifying properties. In this analysis, Φb and η values were determined as 0.83 eV and 1.41, respectively, at room temperature. The device represents photovoltaic features with open-circuit voltage (Voc) of 0.37 V and a short-circuit current (Isc) of 8.17 μA under illumination of 100 mWcm−2. The results represent that the produced junction can be utilized in different photoelectric applications.

Potential of electrolyte-gated transistors for anionic molecule detection: proof of concept using dye solution

The use of electrolyte-gated transistors (EGTs) as sensors can be an advantageous alternative for the detection of anionic molecules due to their capability to detect various ions in solution. In this study, we explore the potential of EGTs as analytical tools for detecting anionic molecules, utilizing a copper phthalocyanine-3,4′,4″,4‴-tetrasulfonic acid tetrasodium salt (CuTsPc) solution as a proof of concept. The results demonstrate the EGT’s capacity in detecting CuTsPc in an aqueous solution, which molecule dissociates into sodium ions (Na+) and CuPc(SO3 −)4 ions, leading to high ionic conductivity and the formation of electrical double layers (EDLs). Varying the concentration of the molecule induced alterations in the EDLs, exhibiting good linearity and sensitivity in the transconductance, and a detection limit of 6.0 × 10−8 mol l−1. Transistors employing the CuTsPc solution as electrolyte operated at low voltages and performed better than water-gated transistors (W-GTs). The transconductance (gm ) value for EGTs using CuTsPc solution reached 1.93 mS, while for W-GTs it was around 0.10 mS. Thus, the CuTsPc solution not only serves as a target-molecule in sensor measurements, but also demonstrates potential as an electrolyte in EGTs, thereby assuming a dual role within the device. The main advantage of the EGTs as an analytical tool is their use as a multiparameter device that enables the detection of the analytes using different phenomena that occur at the EDLs interface and which, consequently, changes the device’s performance.

Bacteria-imprinted impedimetric sensor based on doping-induced nanostructured polypyrrole for determination of Escherichia coli.

Asimple and label-free bacteria-imprinted impedimetric (BIP) sensor for the sensitive measurement of Escherichia colihas been developed. The BIP sensor is fabricated by one-step electropolymerization of pyrrole (functional monomer), copper phthalocyanine-3, 4', 4'', 4'''-tetrasulfonic acid tetrasodium salt (CuPcTs, dopant), and target bacteria (E. coli O157:H7) on aglassy carbon electrode. After the removal of the bacterial template, the established imprinted sites on the CuPcTs-doped polypyrrole film (PPy/CuPcTs) enable the highly selective rebinding of target bacteria and the resulting impedance change of the sensing interface is used to detect the target bacteria. We found that during the electropolymerization process, CuPcTs induced pyrrole to form granular-like nanostructured PPy/CuPcTs with excellent conductivity compared with the PPy film, substantially improving the sensitivity of the proposed sensor. The sensor presented a wide detection range (102 ~ 107CFU⋅mL-1, RSD 1.1% ~ 3.5%) with a limit of detection of21CFU⋅mL-1. Furthermore, the proposed sensor effectively distinguished E. coli O157:H7 from other non-target bacteria and exhibited good practicality with recoveries from 91 to 103% in spiked real samples, indicating the potential utility of the sensor in food safety and environmental monitoring.

Construction of Amphiphilic Indocyanine–Green–Based Langmuir Film and Drop–Casting Film with Photoelectric Conversion Properties

Molecular self–assembly is the automatic formation of functional assemblies of different structural components through weak, reversible, non–covalent interactions on the basis of molecular recognition. Amphiphilic molecules have a natural advantage in self–assembly at the gas/liquid interface. In this work, two amphiphilic molecules with a special molecular structure, indocyanine green (ICG) and a derivative of indocyanine green (CCS), were combined with two dye molecules (tetraphenylporphyrin tetrasulfonic acid hydrate (TPPS) and nickel (II) phthalocyanine–tetrasulfonic acid tetrasodium salt (TsNiPc) for self–assembly through the Langmuir–Blodgett (LB) technique. The nanostructure and assembly behavior in ordered self–assembled films are effectively regulated by inducing dye molecules to form different types of aggregates (H– and J–aggregates). In addition, we prepared composite films containing the same functional components using the conventional drop–casting technique and performed a series of comparative experiments with LB films. The degree of hydrophilicity was found to be related to roughness, with LB composite films being flatter and denser, with the lowest roughness and the best hydrophobicity compared to drop–casting films. Notably, the LB films showed better optoelectronic properties under the same conditions, providing new clues for the application of optoelectronic functional ultrathin film devices.

Chelating Co-reduction Strategy for the Synthesis of High-Entropy Alloy Aerogels.

Aerogels, as three-dimensional porous materials, have attracted much attention in almost every field owing to their unique structural properties. Designing high-entropy alloy aerogels (HEAAs) to quinary and above remains an enormous challenge due to the different reduction potentials and nucleation/growth kinetics of different constituent metals. Herein, a novel and universal chelating co-reduction strategy to prepare HEAAs at room temperature in the water phase is proposed. The addition of chelators (ethylenediaminetetraacetic acid tetrasodium salt, sodium citrate, salicylic acid, and 4,4'-bipyridine) with a certain strong coordination capacity can adjust the reduction potential of different metal components, which is the key to synthesize single-phase solid solution alloys successfully. The optimized AgRuPdAuPt HEAA can be an excellent electrocatalyst for hydrogen evolution reaction (HER) with an ultrasmall overpotential of 22 mV at 10 mA cm-2 and excellent stability for 24 h in an alkaline solution. In situ Raman spectroscopy unveils the enhanced hydrogen evolution reaction mechanism of HEAAs. Overall, this work provides a novel chelating co-reduction strategy for the facile and versatile synthesis and design of advanced HEAAs and broadens the development and utilization of multi-elemental alloy electrocatalysts.

Selective flotation of brucite from calcite using HEDP-4Na as an inhibitor in a SDS system

In this study, the selective adsorption of (1-hydroxyethylidene) bis-phosphonic acid tetrasodium salt (HEDP-4Na) on a calcite surface and its impact on the separation of brucite were examined using a microflotation test, contact angle measurement, zeta potential measurement, X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). The microflotation test revealed that HEDP-4Na selectively inhibited calcite from brucite at pH 10.5 in the sodium dodecyl sulfonate (SDS) system. Under the dosage condition of 180-mg/L HEDP-4Na, a single-mineral floating difference of 73.79% was achieved between brucite and calcite. The contact angle measurement revealed that HEDP-4Na considerably reduced the contact angle of calcite in the SDS system but only weakly affected the contact angle of brucite. Zeta potential analysis and Fourier transform infrared spectroscopy demonstrated that the HEDP-4Na adsorption interfered with the SDS adsorption on the surface of calcite; however, the HEDP-4Na adsorption had little effect on the SDS adsorption on the surface of brucite. XPS and AFM analyses demonstrated that the selectivity and effect of HEDP-4Na on calcite were considerably stronger than those on brucite and the HEDP-4Na adsorption on the calcite surface was significant and strong.

Adsorption of heavy metal ions by sodium chelating PAN fabrics

This study developed a method of filtering heavy metals in water by using dimethylacetamide to dissolve polyacrylonitrile(PAN) fibers and prepare an electrospinning solution. The diameter, surface morphology, and quantitative absorption rate of the electrospun fibers were then explored to determine their efficiency in filtering lead ions (Pb2+) in water. The results revealed that when powdered ethylenediaminetetraacetic acid tetrasodium salt (EDTA-4Na) was mixed with the electrospinning solution, the diameter of the resulting fibers (0.47 μm) was slightly greater than that of the fibers created without adding EDTA-4Na (0.44 μm); this was attributable to the adsorption of the added EDTA-4Na powder on the PAN fiber surface. Quantitative results from ultraviolet–visible spectroscopy revealed that after 180 min, the PAN fabric created using the electrospinning solution chelated with EDTA-4Na exhibited a greater Pb2+ absorption rate (34.47%) than did that created using the solution without EDTA-4Na (9.77%).

An ultra-high power density supercapacitor: Cu(II) phthalocyanine tetrasulfonic acid tetrasodium salt doped polyaniline

In this study, an excellent electrode and supercapacitor performance with aqueous electrolyte exhibiting high operating voltage was obtained. Cu(II) phthalocyanine tetrasulfonic acid tetrasodium salt (CuPcTs) was used as a dopant in the polymerization of aniline on carbon felt electrode (CFt) by one-step hydrothermal method. Scanning electron microscopy (SEM) was used to analyze the morphological structure of PANI and CuPcTs doped PANI electrodes. Chemical analysis of the electrodes was performed using X-Ray diffractometry (XRD) and Fourier transform infrared spectroscopy (FT-IR); thermal properties of the electrodes were investigated using thermogravimetric analysis (TG/DTA). The surface area and pore volume of the electrodes were investigated using Brunauer-Emmett-Teller (BET) analysis. The electrochemical properties of the electrodes were investigated using cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS) methods. With the addition of CuPcTs and the use of graphite plate (GP) as the counter electrode, an asymmetrical supercapacitor was created for pseudocapacitive supercapacitors, in which the properties of redox materials were improved. CuPcTs doped PANI electrode showed a high specific capacitance of 982.2 F g −1 at 5 mV s −1 and showed excellent rate capability at different current densities of charge-discharge tests. Furthermore, wide operating-voltage of 3.2 V exhibited an ultra-high energy density value of 12800 W kg −1 and had an energy density of 764.4 Wh kg −1 . The electrode and supercapacitor displayed retention of capacitance performances of 91.4% and 79.7% after 1000 and 5000 cycles in aqueous electrolyte, respectively. • CuPcTs doped PANI carbon felt electrode was developed for supercapacitor applications. • 3.2 V wide operating voltage supercapacitor with 3.0 M KCI electrolyte. • A high specific capacitance of 982.2 F g −1 at 5 mV s −1 and excellent rate capability at charge-discharge tests. • A -maximum energy density of 764.4 Wh kg −1 and ultra-high power density of 12800 W kg −1 can be obtained for device.

Remediation of Heavy Metal Contaminated Farmland Soil by Biodegradable Chelating Agent GLDA

Chemical leaching is one of the effective methods to remove heavy metals from soil. The effects of biodegradable chelating GLDA (N, N-bis(carboxymethyl)-l-glutamic acid tetrasodium salt) on contaminated farmland soil in four different places (collected from Shangba Village, Shaoguan city (SB); Huaqiao Village, Zhuzhou (HQ); Shaoguan Tielong (TL); and Liantang Village, Lechang (LT), respectively) were studied by the method of leaching. To explore the synergistic effect between GLDA and citric acid, the leaching conditions were also explored. The results showed that the leaching efficiency of heavy metal Pb in soil was improved by adjusting the GLDA solution to reach acidity by adding citric acid. The leaching efficiency of Pb after mixing GLDA and citric acid was higher than the sum of their respective leaching abilities. After leaching with 10 mmol/L of the GLDA solution with a pH of 10.86 for 120 min, the total Pb and the Pb available in the soil decreased significantly. It is known that citric acid has a significant effect on improving the leaching rate of GLDA on soil, and this method can also be applied to other heavy metals, such as Cd. This study provides a low-ecological-risk method for the remediation of heavy metal-contaminated soils.

Fabrication of a novel solar cell using copper phthalocyanine tetrasulfonic acid tetrasodium salt / graphene oxide

Fabrication of a novel solar cell using copper phthalocyanine tetrasulfonic acid tetrasodium salt / graphene oxide

Over 16% efficiency organic/nanostructured Si heterojunction solar cells with a p-doped organic small molecule layer

Organic/nanostructured Si hybrid solar cells have achieved high power conversion efficiency (PCE) and short-circuit current density ( J SC ), due to the excellent light harvesting ability of nanostructured Si. However, the separation of carriers is mainly affected by the low work function of PH1000-type PEDOT:PSS, resulting in poor open circuit voltage ( V OC ). In this work, an efficient and stable MoO 3 -doped copper phthalocyanine-3,4′,4″,4‴-tetra-sulfonated acid tetra sodium salt (TS-CuPc) organic small molecule film was introduced between the heterojunction interfaces. The photogenerated carrier separation is promoted by the enhanced built-in potential ( V bi ) owing to the high work function of TS-CuPc:MoO 3 , which also suppresses the carrier recombination at the surface of nanostructured Si. As a result, for PEDOT:PSS/nanostructured Si photovoltaic devices, the PCE was greatly improved from 14.15% to 16.09%. The excellent charge separation properties and interface passivation effect enable efficient devices to demonstrate the vast potential of this new type of interlayer in photovoltaic applications. • The p-type doping increases the work function of TS-CuPc films. • The interlayer substantially improves charge separation at the Si/organic interface. • The device efficiency is as high as 16.09%, and V OC and FF are improved overall.

Evaluation of GLDA-acid on sludge treatment effect and seed germination analysis

Mixtures of N, N-bis(carboxymethyl)-L-glutamic acid tetrasodium salt (GLDA) with citric acid (CA), glutamic acid (GLU), and aspartic acid (ASP) at the optimal proportion of 1:1, 1:2, and 2:1, respectively. They were employed for heavy metal removal from the sludge. The removal rate of common heavy metals (Cu, Pb, Zn, Ni, Cr, and Cd) and the retention degree of nutrients (total nitrogen, total phosphorus, available-N, Olsen-P, and organic matter) in the treated sludge were analyzed. Fuzzy comprehensive evaluation of the sludge was performed using MATLAB to determine the agricultural grade of the sludge. The sludge after GLDA-acid treatment was mixed with soil at different proportions, and Chinese cabbage, cucumber, and wheat were cultured. SPSS was used for survival analysis to analyze the feasibility of the sludge agriculture. The results showed that the optimal ratio of GLDA-CA and GLDA-GLU was 1:2 and that of GLDA-ASP was 1:1. After GLDA-acid treatment, the sludge was classified as Grade A agricultural sludge based on MATLAB fuzzy comprehensive evaluation and analysis. When the amount of sludge added was 20%, the growth of Chinese cabbage, cucumber, and wheat was promoted. Survival analysis further proved that the amount of sludge only affected the median germination time. Without considering the economic benefits, GLDA-acid can be preferred for sludge treatment, which can not only effectively remove heavy metals in sludge, but also have a small impact on agricultural use.

Facile membrane preparation from colloidally stable metal-organic framework-polymer nanoparticles

UiO-MOFs are based on zirconium cluster and carboxylic acid linkers. They have excellent chemical and thermal stability, tolerance to linkers of different length and functionalities, making them good candidates for a broad range of applications. However, difficulties of processing the polycrystalline powder of MOFs limit their application. Here, we report for the first time the synthesis of the UiO-66 in the presence of a well-defined poly (methacrylic acid)-b-poly (methyl methacrylate) (PMAA-b-PMMA) nanoparticles (NPs) prepared via Reversible Addition−Fragmentation Chain-transfer Polymerization controlled Polymerization Induced Self-Assembly (RAFT-PISA). The PMAA-b-PMMA NPs with multi carboxylic acid groups on their surface, well defined in shape and size, act as multivalent connecting agent for the synthesis of the UiO-66. The resulting colloidally stable UiO-polymer NPs are crystalline, porous, and with an improved processability as was demonstrated by the preparation of a thin film nanocomposite (TFN) membrane. This membrane was applied in the filtration of Nickel (II) phthalocyanine-tetrasulfonic acid tetrasodium salt aqueous solution obtaining a water permeability circa 20 L m−2 h−1 bar−1 with a rejection of more than 90%. This unprecedented facile synthesis approach could be universally applied to other MOFs, expanding their application in different fields due to their enhanced processability.

Defect-dominated carbon deposited Pd nanoparticles enhanced catalytic performance of formic acid dehydrogenation

The defect-rich characteristic nanostructure carbon favors the changing polarity and electron distribution in carbon matrix, thus facilitating an efficient adsorption of ions. Herein, a B,N,F-tridoped carbon material is successfully prepared on defect-rich sites by directly calcining two sodium salts, namely ethylenediaminetetraacetic acid tetrasodium salt (Na4EDTA) and ammonium tetrafluoroborate (NH4BF4). B refers to electron-donating atoms while F and N are electron-accepting atoms. The co-existence of electron-donating and electron-accepting atoms causes an asymmetrical spin and charge density, favoring palladium nanoparticles (Pd NPs) well dispersed on the carbon matrix. The heteroatoms efficiently control over the growth of Pd NPs and regulate the internal electron density. The catalytic performance is significantly enhanced with the obtained Pd/BNF-C catalyst for formic acid dehydrogenation, which has a lower activation barrier (36.4 kJ/mol) and a better reusability than those of free-heteroatom catalysts. The efficiency might be attributed to the strong interaction between Pd NPs and heteroatoms, and the electrons transfer from carbon material to Pd NPs, with benefits including the significant coupling effect of B,N,F-tridoping down to the atomic scale, abundant surface active defects, in-plane nanopore defects and more adjacent metal active sites.

Selective removal of Cr (VI) from hydrometallurgical effluent using modified cellulose nanocrystals (CNCs) with succinic anhydride and ethylenediaminetetraacetic acid: Isotherm, kinetics, and thermodynamic studies

AbstractBiological sources are renewable basic resources that may be used for several purposes, including the development of green materials for the removal of heavy metal ions. Cellulose nanocrystals (CNCs) extracted from waste papers via acid hydrolysis were modified and utilized as adsorbents to remove Cr (VI) ions from metallurgical effluent in this work. X‐ray diffraction, scanning electron microscopy, Fourier‐transform infrared spectroscopy, thermogravimetric analysis, and zeta potentiometer were used to characterize the CNCs. The CNCs treated with succinic anhydride and ethylenediaminetetraacetic acid tetrasodium salt have thin particle sizes and are porous. The carboxylate functional group is primarily engaged in the coordination and selective removal of metal ions (–COO2−) and thermal degradation of 85%, observed at temperatures between 250–380°C. On the surface of the modified CNCs, the zeta potential data showed a decrease in negative value. The results revealed that the modified CNCs had a maximum adsorption capacity of 387.25 ± 0.88 mg L−1 at pH 5, at CNCs doses of 25 and 400 mg L−1 as starting concentrations. The adsorption equilibrium period was 300 min and the temperature was 313 K. The equilibrium results fit the Langmuir isotherm model with an R2 of 0.993 and a qmax of 340 ± 0.97. The Chi‐square (X2) and Marquardt's percent standard deviation tests confirmed that the adsorption process was pseudo‐second‐order with an R2 of 0.998, and the Elovich model revealed that Cr (VI) complexed with the adsorbent's functional groups. The reaction was endothermic due to positive ΔH and spontaneous due to negative ΔG. The positive ΔS indicates that the adsorption process enhances the unpredictability of the solid/liquid interface, according to thermodynamic analysis. After acid treatment, the CNCs may be effectively reused for six cycles with an adsorption capacity of 220 ± 0.78 mg g−1.

Monitoring the Cd2+ release from Cd-containing quantum dots in simulated body fluids by size exclusion chromatography coupled with ICP-MS.

Quantification of Cd2+ release from Cd-containing quantum dots (QDs) is of fundamental importance to elucidate its toxicity to organisms, but remains a great challenge due to the lack of appropriate analytical method. Herein, a facile method based on size exclusion chromatography (SEC) combined with inductively coupled plasma mass spectrometry (ICP-MS) was developed for separating and quantifying the QDs and counterpart ions. By using the mixture of sodium dodecyl sulfate (SDS) and ethylenediaminetetraacetic acid tetrasodium salt (EDTA) as the mobile phase, the defect of QD and ion adsorption onto the SEC column was overcome, thus realizing the accurate quantification of ionic species. Besides, the concentration of QDs was achieved through subtracting the ion concentration from the total concentration. Selecting CdSe@ZnS as the typical QDs, the Cd2+ release process in four typical simulated body fluids, namely, simulated gastric fluid, simulated sweat, Gamble's solution, and artificial lysosomal fluid, was monitored using the developed SEC-ICP-MS method. The media pH is identified as the decisive factor which controls the dissolution of ZnS shells and also the Cd2+ release kinetics and final concentration. Our results suggest that the oral pathway for QD uptake poses the biggest risk to human health.

Sulfonated Phthalocyanine Redox Flow Cell for Electrochemical Water Desalination

A reliable clean water supply is now one important and challenging issue for the human society. With the facts that only 0.4% of the water on earth is readily drinkable and 98% of the water is saltwater, water desalination for clean water production has become a key strategic solution to satisfy the increasing global water demand. Over the years, different saltwater desalination technologies were researched and developed, including reverse osmosis membrane desalination (RO), electrodialysis (ED), capacitive desalination (CDI) and multi-effect distillation (MED). However, some inherent technical issues, like high operation cost, large capital cost and/or low desalination capacity, associate with these existing technologies that lead to a high clean water production cost and limit their applications. Thus, there is a need of new water desalination technology that can purify saltwater with low cost and high efficiency.In this work we report a new water-soluble nickel phthalocyanine tetrasulfonic acid tetrasodium salt (NiPcTATS)-based redox flow desalination battery (RFDB) for safe, effective and efficient water-salt separation. The fabricated RFDB cell exhibited a high desalination rate at 3.4 gNaCl/(molNiPcTATS∙hr) even with a low 0.5 V cell voltage and required as low as 11.5 kJ/mol salt in energy consumption. The cell showed excellent reversibility and durability for long-term operation, benefiting from the fast-redox kinetics and chemical stability of the redox couple. With no consumption of the redox couple and energy recovery during the salination process, this new method provides a continuous desalination capability with unlimited salt removal capacity. We also demonstrated the use of simple solar panel for effectively driving the RFDB cell, proving it a promising and practical technology for clean water production in remote places like islands and ships.