Potassium Ferrocyanide Solution Research Articles

Modification Of a Screen-Printed Carbon Electrode with Nanoporous Gold by Electrodeposition and Dealloying of a Gold-Copper Alloy

In this study, a three-dimensional structure of nanoporous gold (NPG) was made by selectively corroding copper (Cu) from gold-copper (Au-Cu) alloys using a two-step electrochemical method. Given its large surface area and interconnected porous network, nanoporous gold is a suitable material for the advancement of electrochemical sensors. The screen-printed carbon electrode (SPCE) modified with nanoporous gold (NPG/SPCE) was fabricated by electrodepositing a gold-copper alloy from gold ion (Au3+) and copper ion (Cu2+) solution via cyclic voltammetry (CV) by scanning from -0.3 V to -0.8 V for 80 cycles. The copper is then removed via a dealloying process in 3M HNO3 using the cyclic voltammogram (CV) method by scanning potential from 0 V to +1.0 V for 100 cycles at 100 mV/s. The morphology, elemental composition, and electrochemical active surface area (ECSA) of NPG/SPCE electrodes were characterized using FESEM, EDX, and CV analysis, respectively. The electrochemical performance of the NPG/SPCE was compared with bare SPCE in a 10 mM potassium ferrocyanide (K4FeCN6) solution using cyclic voltammetry. The morphological study using FESEM revealed that the NPG/SPCE had an average pore diameter of 53 nm. The quantification of elements using EDX shows that 84 % of the copper in the electrodeposited gold-copper alloy electrode was successfully removed by the dealloying process. The higher number of cycles during the dealloying process led to producing NPG with higher ECSA electrodes. The ECSA of NPG/SPCE is 12 times greater than that of bare or unmodified SPCE in an equivalent geometrical area. NPG/SPCE has a much better electron transfer surface than bare SPCE due to its high surface area and gold surface properties, making it a potential sensing material for biosensing applications.

The Fast Quantification of Vitamin B12 in Milk Powder by High-Performance Liquid Chromatography-Inductively Coupled Plasma Mass Spectrometry.

This study presents a new technique for determining vitamin B12 in milk powder using high-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS). We used ultrasonics with potassium ferrocyanide and zinc acetate solutions to extract the samples. 59Co was employed as the analytical target for cyanocobalamin. It was separated using a Phenomenex Luna 5 μm C18 (250 × 4.6 mm) chromatographic column with a mobile phase consisting of 1.6 mmol/L EDTA and 0.4 mmol/L KH2PO4 in a 60% v/v methanol solution (pH = 4.0). The sample has an excellent separating degree for free cobalt and cyanocobalamin, and isocratic elution can be finished within 4.0 min. To eliminate the matrix interference due to the presence of milk powder, we applied collision mode (KED). The linear range of cyanocobalamine ranged from 1.0 μg/L to 20 μg/L, with correlation coefficients (r2) of 0.9994. The limit of detection (LOD) was 0.63 μg/kg, and the limit of quantitation (LOQ) was 2.11 μg/kg. The mean recoveries were in the range of 87.4-103.6%. The accuracy and precision of the developed method are well suited for the fast quantification of the trace vitamin B12 in milk powder.

Construction of a self–reporting molecularly–imprinted electrochemical sensor based on CuHCF modified by rGNR–rGO for the detection of zearalenone

A self–reporting molecularly–imprinted electrochemical sensor is prepared for the detection of Zearalenone (ZEA). Firstly, the reduced graphene nanoribbons and reduced graphene oxide (rGNR–rGO) were simultaneously modified onto a glassy carbon electrode (GCE) to improve the sensor's sensitivity. After electrodepositing copper nanoparticles onto the rGNR–rGO/GCE, cyclic voltammetry scanning was performed in potassium ferrocyanide solution, and copper hexacyanoferrate (CuHCF) was deposited onto rGNR–rGO/GCE to further improve the sensor's sensitivity while giving it self–reporting capability. Then, molecularly–imprinted polymer films were prepared on the CuHCF/rGNR–rGO/GCE to ensure the selectivity of the sensor. It is found that the linear range of ZEA detection by the constructed sensor is 0.25–500 ng·mL −1, with a detection limit of 0.09 ng·mL −1. This sensor shows the merits of good selectivity, high sensitivity and accurate detection, providing a great possibility for the precise detection of low concentration ZEA in food.

New Sorbents Based on Polyacrylonitrile Fiber and Transition Metal Ferrocyanides for 137Cs Recovery from Various Composition Solutions

For the first time, new sorbents based on polyacrylonitrile (PAN) fiber and transition metal ferrocyanides were obtained. The main difference between the obtained sorbents and the existing ones is the stage of preliminary preparation of the initial support by converting it into the forms PAN-Fe(OH)3 or PAN-MnO2, due to which additional ion exchange groups (carboxyl, carbonyl, etc.) are formed, which increases the amount of ferrocyanide fixed to the support. The best components and conditions for the synthesis of new sorbents were determined (concentration (0.1–0.2 mol/L), as well as pH (1 for sorbents based on PAN-Fe(OH)3, and 1–5—PAN-MnO2) of potassium ferrocyanide solution, concentration of transition metal salts (0.02 mol/L), temperature conditions). The influence of the studied solution composition (pH, concentration of Na+, K+, NH4+ ions) on the cesium distribution coefficients during its recovery by the obtained sorbents was assessed. The possibility of cesium recovery from solutions with pH 1–9 containing macro quantities of cations was demonstrated. The sorbents derived were characterized by modern structural methods such as infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy with EDS analysis. A study of the trace amount sorption of 137Cs was carried out in comparison with commercially available highly efficient sorbents (FNS-10 and Termoksid-35), and it was shown that the resulting sorbents are not inferior to industrial ferrocyanide sorbents and can be used for 137Cs selective sorption from technological solutions and natural waters.

Modification of graphene oxide with imidazolium-based ionic liquid for significant sorption of La(III) and Pr(III) from aqueous solutions

A straightforward ferrocyanide immobilization on the surface of graphene oxide (GO) was conducted for rapid and efficient adsorption capacity for lanthanum and praseodymium from an aqueous solution. The GO was mixed with 1-methyl imidazole in the presence of epichlorohydrin to form GO-imidazole-Cl and thereafter suspended in a potassium ferrocyanide solution to fabricate GO-imidazole-FeCN. The prepared materials were characterized with different advanced techniques confirming the preparation method. The adsorption ability of GO-imidazole-FeCN towards La(III) and Pr(III) ions was evaluated. Moreover, the adsorption isotherm showed that the sorption process was fitted with the Langmuir isotherm model with a considerable maximum adsorption capacity of 781.25 mg g−1 for La(III) and 862.07 mg g−1 for Pr(III). The thermodynamic studies showed that the adsorption of both metal ions was spontaneous and endothermic. In addition, the adsorbent showed excellent adsorption–desorption behavior over 5 times, suggesting that GO-imidazole-FeCN may be considered a potential candidate for La(III) and Pr(III) removal from different metal ions which present in fission products.

Synthesis, chracterization, and analytical application of silver dopamine magnetic nanomaterial

Silver nanocubes decorated dopamine-magnetic (AgNCs-Dop@ Fe3O4) based nanomaterial has been synthesized for analytical application. The formation of AgNCs-Dop@ Fe3O4 materials was confirmed by X-ray powder diffraction, scanning electron microscopy, energy dispersive x-ray analysis, fourier transform infrared spectroscopy, and atomic force microscopy. Electrochemical characteristics of AgNCs-Dop@Fe3O4 NPs were investigated for histamine using chronoamperometry, linear sweep voltammetry, cyclic voltammetry, and electrochemical impedance spectroscopy. The AgNCs-Dop@Fe3O4 NPs (2 μL) drop casted electrode showed higher catalytic activity for histamine in potassium ferrocyanide and PBS solution. The AgNCs-Dop@Fe3O4 NPs modified electrode showed 1.2 μA/ μM sensitivity, linear range from 0.1 to 0.7 μM (R2 = 0.990), and LOD of 0.0025 μM for histamine. The proposed material showed good stability, selectivity, and sensitivity for histamine in interferences with good recoveries (>96%). The silver nanocubes decorated dopamine-magnetic nanomaterials can be used successfully as a screening tool for sensing histamine in various analytical samples.

Development of a novel microfluidic biosensing platform integrating micropillar array electrode and acoustic microstreaming techniques

Quantifying biomarkers at the early stage of the disease is challenging due to the low abundance of biomarkers in the sample and the lack of sensitive techniques. This article reports the development of a novel microfluidic electrochemical biosensing platform to address this challenge. The electrochemical sensing is achieved by utilizing a micropillar array electrode (μAE) coated with 3D bimetallic Pt–Pd nanotrees to enhance the sensitivity. A bubble-based acoustic microstreaming technique is integrated with the device to increase the contact of analyte molecules with the surface of electrodes to further enhance the electrochemical performance. The current density of Pt–Pd NTs/μAE with acoustic microstreaming is nearly 22 times that of the bare planar electrode in potassium ferrocyanide solution. The developed biosensor has demonstrated excellent sensing performance. For hydrogen peroxide detection, both the Pt–Pd NTs/μAE and acoustic microstreaming contribute to the sensitivity enhancement. The current density of the Pt–Pd NTs/μAE is approximatively 28 times that of the bare μAE. With acoustic microstreaming, this enhancement is further increased by nearly 1.6 times. The platform has a linear detection range of 5–1000 μM with a LOD of 1.8 μM toward hydrogen peroxide detection, while for sarcosine detection, the linear range is between 5 and 100 μM and LOD is 2.2 μM, respectively. Furthermore, the sarcosine biosensing shows a high sensitivity of 667 μA mM−1∙cm−2. Such a sensing platform has the potential as a portable device for high sensitivity detection of biomarkers.

The Redox‐Mediated Nickel–Metal Hydride Flow Battery

AbstractEach battery technology possesses intrinsic advantages and disadvantages, e.g., nickel–metal hydride (MH) batteries offer relatively high specific energy and power as well as safety, making them the power of choice for hybrid electric vehicles, whereas aqueous organic flow batteries (AORFBs) offer sustainability, simple replacement of their active materials and independent scalability of energy and power, making them very attractive for stationary energy storage. Herein, a new battery technology that merges the above mentioned battery technologies through the use of redox‐mediated reactions is proposed that intrinsically possesses the main features of each separate technology, e.g., high energy density of the solid active materials, easy recyclability, and independent scalability of energy and power. To achieve this, Ni(OH)2 and MHs are confined in the positive and negative reservoirs of an AORFB that employs alkaline solutions of potassium ferrocyanide and a mixture of 2,6‐dihydroxyanthraquinone and 7,8‐dihydroxyphenazine‐2‐sulfonic acid as catholyte and anolyte, respectively. An energy density of 128 Wh L–1 is achieved based on the capacity of the reservoirs leaving ample room for improvement up to the theoretical limit of 378 Wh L–1. This new battery technology opens up new market opportunities never before envisaged, for redox flow batteries, e.g., domestic energy storage and heavy‐duty vehicle transportation.

Novel sinuous band microelectrode array for electrochemical amperometric sensing

Pursuing a higher response signal is the core challenge in improving the detection performance of a microelectrode-based amperometric electrochemical sensor. Band microelectrode arrays (bMEAs) are attractive due to their high response current and economical fabrication process. However, further amplifying the response current by arranging the array more compactly or increasing its size is generally hindered by the shielding effect or the restricted construction region. A novel array of sinuous band microelectrodes (sbMEA) is proposed, produced by deforming a bMEA by tilting and bending. Its response and diffusion characteristics are simulated and analyzed. The effects of structural parameters on its performance are revealed, and their optimal value is deduced. The simulation demonstrates that a sbMEA can generate a larger current than a MEA of traditional shape. Production of such a sbMEA does not involve any additional fabrication costs compared with a bMEA. Cyclic voltammetry (CV) tests with potassium ferrocyanide solution verify the theoretical performance of the sbMEA, and a 10% higher current was obtained compared to the corresponding bMEA.

Determination of Diosmin in Pharmaceutical Products with Chemically Modified Voltammetric Sensors.

In this paper, the electrochemical behavior of two types of sensors based on modified screen-printed electrodes (one screen-printed electrode based on carbon (SPCE) and another screen-printed electrode modified with Prussian Blue (PB/SPCE)) was studied with the aim of sensitive detection of diosmin, an active pharmaceutical compound from the class of flavonoids. The scan electron microscopy technique was used for the morphological characterization of PB/SPCE. The preliminary analysis assessed the electrochemical behavior of SPCE and PB/SPCE in KCl solution and in a double solution of potassium ferrocyanide–potassium chloride. It was shown that the active area of PB/SPCE is superior to the one of SPCE, the greater sensitivity being related with the presence of the electroactive modifier. Similarly, in the case of diosmin detection, the PB/SPCE sensor detect more sensitivity the diosmin due to the electrocatalytic effect of PB. From the study of the influence of reaction rate on the sensor’s electrochemical response, it was shown that the detection process is controlled by the adsorption process, the degree of surface coverage with electroactive molecules being higher in the case of PB/SPCE. From the PB/SPCE calibration curve, it wasdetermined that it has high sensitivity and low detection and quantification limit values (limit of detection 5.22 × 10−8 M). The applicability of the PB/SPCE sensor was confirmed by sensitive analysis of diosmin in pharmaceutical products. The voltammetric method is suitable for the detection and quantification of diosmin in pharmaceutical products. The method is simple, accurate, and quick and can be used in routine analysis in the examination of the quality of pharmaceutical products and other types of samples.

Recovery of Gold from Ore with Potassium Ferrocyanide Solution under UV Light

In this study, potassium ferrocyanide, a nontoxic cyanide precursor in dark and diffuse reflection environment, was applied as reagent for the leaching of gold. The free cyanide ions could gradually release from potassium ferrocyanide solution under the ultraviolet light. Orthogonal leaching experiments were performed in gold ore to analyze the effect of solution pH, potassium ferrocyanide dosage, and temperature in a potassium ferrocyanide solution system under UV light. Response surface methodology (RSM) was applied to explore the role of potassium ferrocyanide in gold leaching; optimized results showed that the gold recovery reached 67.74% in a high-alkaline environment at a 12.6 pH, 3.8 kg/t potassium ferrocyanide dosage, 62 °C, and irradiance of 10 mW·cm−2. The gold leaching kinetics were monitored by quartz crystal microbalance with dissipation (QCM-D) of potassium ferrocyanide solution. The results indicate that the gold extraction process could be divided into two stages: adsorption and leaching, and a rigid adsorption layer formed on the reaction surface. Furthermore, X-ray photoelectron spectroscopy (XPS) analysis of the gold sensor surface after leaching reaction showed that –C≡N appears on the gold sensor surface, and the gold is oxidized to form AuCN complexes.

Amperometric detection of triclosan with screen-printed carbon nanotube electrodes modified with Guinea Grass (Panicum maximum) peroxidase

Triclosan is a compound with antimicrobial activity broadly used in consumer products. Because of its well documented toxicity, the amount of triclosan present in different products needs to be tightly controlled. This paper outlines a new amperometric sensor for triclosan detection consisting of a screen-printed carbon nanotube electrode (SPCNE) modified w ith Guinea grass peroxidase (GGP). The GGP-modified S PCNE was a ble t o d etect an enhanced electrochemical response of triclosan, unlike the bare SPCNE. The cyclic voltammograms of the GGP-modified SPCNE in a solution of potassium ferrocyanide showed an increase in the current values and linearity between scan rates and oxidation peak currents, suggesting a surface controlled process. The GGP-modified SPCNEs howed an excellent electrocatalytic activity to triclosan oxidation, at a redox potential of 370 mV, in the presence of hydrogen peroxide, exhibiting a linear response between 20 mM to 80 mM and a detection limit of 3 µM. This new amperometry system, based on carbon nanotubes integrated with GGP, becomes a potential tool for environmental analysis and food quality control.

Wall to Bed Mass Transfer in the Presence of Double Cone Promoter in a Three Phase Fluidized Bed with Conical Entry of Electrolyte

Abstract Investigations have been carried out experimentally to study the effect on wall-to-bed mass transfer coefficient in presence of double cone promoter in a three-phase fluidized bed with a conical entry of electrolyte. The system chosen was an electrolyte as liquid phase, glass spheres of different diameters as solid phase and inert nitrogen as gas phase. The electrolyte was an equimolar solution of potassium ferricyanide and potassium ferrocyanide each of 0.01 N with 0.5 N sodium hydroxide as indifferent electrolyte. The reaction considered was the reduction of ferricyanide ion. The experiment had been carried out at temperature range of 36 to 38 o C at which the physical property values of the electrolyte were known from literature. The mass transfer coefficient was computed from the measured limiting current. It was found that the mass transfer coefficient was relatively independent of liquid velocity within the range covered in the present experiment. The k L increased marginally with increasing gas velocity. The k L was not influenced significantly by particle size and diameter of promoter within the present study range. The entire experimental data have been correlated in terms of Coulburn j D -factor and particle Reynolds number. Keywords: Mass transfer coefficient based on liquid side, k L, Coulburn j D -factor, particle Reynolds number, Rep , Froude number based on gas velocity, Fr g , Schmidt number, Sc

Reformation of the surface of powdered activated carbon (PAC) using covalent organic polymers (COPs) and synthesis of a Prussian blue impregnated adsorbent for the decontamination of radioactive cesium

Prussian blue (PB) is known to selectively adsorb cesium (Cs), with a high adsorption efficiency. However, it is difficult to collect it after adsorption, which increases the risk of secondary environmental pollution. In this study, covalent organic polymers (COPs) were used to reform the surface of powdered activated carbon (PAC) particles in order to stably immobilize PB, with the aim of developing an adsorbent impregnated with PB (COP-PAC-PB). PAC particles reformed with COPs (COP-PAC) were analyzed using TEM (EDS) and FT-IR techniques, and it was found that COPs were successfully synthesized on the surface of COP-PAC particles. COP-PAC-PB particles were synthesized by reacting PAC particles with iron(III) chloride and potassium ferrocyanide solutions in order, to synthesize PB within the pores of COPs (in situ). COP-PAC-PB particles were analyzed using XRD and FT-IR techniques, and peaks showing the general characteristics of PB were observed, which indicated that PB existed on the surface of COP-PAC-PB particles. PB was synthesized on the surface of the non-reformed groups (PAC and Ox-PAC) using the same method. In addition, UV–vis analysis was performed to compare the characteristics of PB desorbed from the non-reformed and reformed groups immediately after synthesizing and washing them. In the non-reformed groups (PAC-PB and Ox-PAC-PB), a large amount of PB was desorbed while they were washed 6 times. For COP-PAC-PB, however, a small amount of PB was desorbed during the first washing, but no desorbed PB was observed thereafter. The maximum Cs adsorption capacity of COP-PAC-PB particles was 19 mg/g, and its removal efficiency of radioactivity cesium (Cs-137, 60 Bq/kg) was 97.3%. In this study, the surface of PAC particles was effectively reformed using COPs, and an adsorbent to which PB was stably immobilized was developed.

Design and Finite Element Model of a Microfluidic Platform with Removable Electrodes for Electrochemical Analysis

A microfluidic platform for hydrodynamic electrochemical analysis was developed, consisting of a poly(methyl methacrylate) chip and three removable electrodes, each housed in 1/16” OD polyether ether ketone tube which can be removed independently for polishing or replacement. The working electrode was a 100-μm diameter Pt microdisk, located flush with the upper face of a 150 μm × 20 μm × 3 cm microchannel, smaller than previously reported for these types of removable electrodes. A commercial leak-less reference electrode was utilized, and a coiled platinum wire was the counter electrode. The platform was evaluated electrochemically by oxidizing a potassium ferrocyanide solution at the working electrode, and a typical limiting current behavior was observed after running linear sweep voltammetry and chronoamperometry, with flow rates 1−6 μL/min. While microdisk channel electrodes have been simulated before using a finite difference method in an ideal 3D geometry, here we predict the limiting current using finite elements in COMSOL Multiphysics 5.3a, which allowed us to easily explore variations in the microchannel geometry that have not previously been considered in the literature. Experimental and simulated currents showed the same trend but differed by 41% in simulations of the ideal geometry, which improved when channel and electrode imperfections were included.

Study on electrochemical biosensor based on screen-printed electrode

It is known that redox reaction can take place among the solutions of potassium ferrocyanide (K4[Fe(CN)6]), glucose (C6H[Formula: see text]O6) and glucose oxidase (Glucose Oxidase, GOD). In this work, the method of electrochemical biosensor detection based on screen printed electrode was used to observe the redox reaction among these solutions. The relationship between redox reaction and parameters was studied by examining the effects of concentration and scanning speed of three solutions.

The light triggered dissolution of gold wires using potassium ferrocyanide solutions enables cumulative illumination sensing

Electronic systems with on-demand dissolution or destruction capabilities offer unusual opportunities in hardware-oriented security devices, advanced military spying and controlled biological treatment. Here, the dissolution chemistry of gold, generally known as inert metal, in potassium ferricyanide and potassium ferrocyanide solutions has been investigated upon light exposure. While a pure aqueous solution of potassium ferricyanide–K3[Fe(CN)6] does not dissolve gold, an aqueous solution of potassium ferrocyanide–K4[Fe(CN)6] irradiated with ambient light is able to completely dissolve a gold electrode within several minutes. Photo activation and dissolution kinetics were assessed at different initial pH values, light irradiation intensities and ferrocyanide concentrations. Addition of small amounts of the heavy metal thallium (260 ppb) also provides tunability of the dissolution kinetics. An investigation of the involved chemical and physical processes of photochemistry, cyanide diffusion and surface reaction results in an understanding of the rate limiting steps and yields an overall transformation of irradiated light energy to dissolved gold of 2.6%. A potential application of this novel gold dissolution method as a cumulative light sensor is demonstrated and discussed.

Development of Adsorbent Prussian Blue (PB) Impregnated through the Grafting of Covalent Organic Polymers (COPs) for the Removal of Radioactivity Cesium (Cs-137)

This study aims to utilize Prussian Blue (PB) to develop a high performance adsorbent for removing radioactive cesium from radioactive accidents. Prussian blue (PB) can adsorb selectively to cesium (Cs), which is high in adsorption efficiency, but has a disadvantage that it is difficult to recover after adsorption, so there is a high concern about secondary environmental pollution. Therefore, this study modified the surface of powder activated carbon (PAC) particles by using covalent organic polymer (COP) for stable immobilization of PB, and developed a PB-impregnated adsorbent (COP-PAC-PB). Synthesis of COP-PAC-PB was performed by sequentially reacting with iron (III) chloride and potassium ferrocyanide solution to synthesize PB in COP pore (In-situ). The maximum adsorption of COP-PAC-PB on cesium was 19 mg / g and the removal efficiency for radioactivity cesium (Cs-137, 60 Bq / kg) was 97.3%. In addition, PB was synthesized by the same method as that of COP-PAC-PB, which is a modification product of the unmodified group (PAC, Ox-PAC), and UV-vis analysis was performed to compare PB desorption characteristics after washing Respectively. In the unmodified group (PAC-PB, Ox-PAC-PB), a large amount of PB was desorbed when washed once to 6 times. In the case of COP-PAC-PB, it was not. As a result, the surface of the PAC particles was effectively modified using COP, and the adsorbent with Prussian blue stably immobilized was developed.

Wall-to-bed mass transfer in a three-phase fluidized bed with coaxially placed string of spheres internal

Turbulent promoters are generally used to realize enhancement in heat and mass transfer rates. With a view to exploit this advantage for the favor of obtaining magnitudes of improvements in mass transfer rates in electrochemical processes, in the present study experiments were conducted in three phase fluidized bed electrochemical cells in the presence of coaxially placed string of spheres. Diffusion controlled electrode reactions were employed to obtain limiting current densities, and hence, mass transfer coefficients. An equimolar potassium ferrocyanide and potassium ferricyanide solution in the presence of sodium hydroxide supporting electrolyte was used as the liquid phase. Glass spheres of different sizes were employed as fluidizing solids and nitrogen was used as the inert gas phase. In three phase fluidized bed, mass transfer coefficient increased with increasing sphere diameter and particle diameter. The parametric effect of gas and liquid velocities on mass transfer coefficient was found to be marginal. The mass transfer coefficient was found to decrease with increase in pitch. A correlation to predict mass transfer coefficient has been developed by using least squares regression analysis.

In-situ preparation of iron(III) hexacyanoferrate nano-layer on polyacrylonitrile membranes for cesium adsorption from aqueous solutions

Ion-exchange adsorption is an effective method for separating cesium and rubidium from other alkaline metal ions in aqueous solutions. Herein, we developed a novel and facile method for in-situ preparation of Prussian blue (PB) nano-layer on porous polyacrylonitrile (PAN) membranes by heterogeneous nucleation in potassium ferrocyanide solution and then growth in FeCl3 solution, or potassium ferrocyanide solution as single precursor. The effects of reactant concentrations and reaction time on the PB layer, the static adsorption, dynamic adsorption, desorption and reuse of PB membranes were investigated. The results showed that the maximum adsorption capacity of PB nano-layer for cesium attains 0.714mmolg−1 (25°C), and the ideal selectivity factor of Cs+ vs. Li+, K+, and Na+ is found to be 41.76, 35.50, and 23.67 respectively. Compared with the PB powder, the immobilized PB on membrane surface does not deteriorate in the adsorption performance. NH4Cl aqueous solution exhibits excellent eluting effect, and the membrane can be reused for 5 times without apparent deterioration, indicating practical perspective in adsorption of cesium and rubidium from aqueous solutions.