Remarkable Acid Stability of Polypyrrole‐MoS4: A Highly Selective and Efficient Scavenger of Heavy Metals Over a Wide pH Range

The new material polypyrrole/MoS₄^2?(MoS₄‐Ppy), prepared by ion‐exchange of NO₃‐ of NO₃‐Ppy with MoS₄^2?, displays high acid stability and excellent uptake for heavy metal ions such as Hg²⁺, Ag⁺, Cu²⁺, and Pb²⁺. The different maximum adsorption capacities (q_m) for Cu²⁺, Pb²⁺, Hg²⁺, and Ag⁺ depend on the various binding modes arising from the different thiophilicity of these metal ions. The removals of Ag⁺ and Pb²⁺ reach >99.6% within 5 min, and for highly toxic Hg²⁺, >98% removal achieves at 1 min. At strong acid limit, the exceptional q_m(Ag⁺) of 725 mg g^?1 places the MoS₄‐Ppy at the top of materials for such removal. Uptake kinetics of Ag⁺, Hg²⁺, and Pb²⁺ is extremely fast: >99.9% removal rates at wide pH range (0.5–6) within 1–5 min. Also, at strongly acidic conditions (pH ≈ 1), for highly toxic Hg²⁺, <2 ppb concentration can be achieved, accepted as safe limit. The MoS₄‐Ppy demonstrates an outstanding ability to separate low‐concentrated Ag⁺ from high concentrated Cu²⁺ especially under strong acidic conditions (pH ≈ 1), showing a large separation factor SF_Ag/Cu (K_d^Ag/K_d^Cu) of 10⁵ (>100). MoS₄‐Ppy is a superior and novel sorbent material for water remediation applications as well as precious metals recovery.     

Tailoring Amino‐Functionalized Graphitic Carbon‐Encapsulated Gold Core/Shell Nanostructures for the Sensitive and Selective Detection of Copper Ions

The effective transfer of strong electromagnetic field from the gold core through the coating shell represents the most significant challenge for the applications of plasmonic nanoparticles. This study applies a one‐step arc discharge method to synthesize graphitic carbon‐encapsulated gold nanoparticles (Au@G NPs) functionalized with amino groups uniformly via adding NH₃ into He background gas. By tailoring the coating shell into few‐layered graphene, a strong localized surface plasmon resonance (LSPR) absorption band is achieved. The NH₃ introduces H radicals to strengthen the LSPR characteristic by etching the coating graphitic shell, as well as provides dissociated NH or NH₂ species to functionalize the surfaces with amino groups. With an LSPR‐based colorimetric method, it is demonstrated that trace Cu²⁺ ions can be detected rapidly with excellent sensitivity (as low as 10 × 10^‐9m linearly) and selectivity against other metal ions (Na⁺, K⁺, Mg²⁺, Ca²⁺, Co²⁺, Fe²⁺, Cd²⁺, Pb²⁺, and Hg²⁺ ions) by amino‐functionalized Au@G NPs in water samples.     

Optical Sensor Based on Nanomaterial for the Selective Detection of Toxic Metal Ions

A heterogeneous “naked‐eye” colorimetric and spectrophotometric cation sensor, SNT‐ 1 , was prepared by immobilization of the azo‐coupled macrocyclic receptor 1 on a silica nanotube (SNT) via sol–gel reaction. The optical sensing ability of SNT‐ 1 was studied by addition of metal ions such as Ag⁺, Co²⁺, Cd²⁺, Pb²⁺, Zn²⁺, Fe³⁺, Cu²⁺, and Hg²⁺ (all as nitrates) in water. Upon the addition of Hg²⁺ in suspension SNT‐ 1 resulted in a color change from yellow to violet. This is novel rare example for chromogenic sensing of a specific metal ion by inorganic nanotubes. On the other hand, no significant changes in color were observed in the parallel experiments with Co²⁺, Cd²⁺, Pb²⁺, Zn²⁺, Fe³⁺, Cu²⁺, and Ag⁺. These findings confirm that SNT‐ 1 can be useful as chemosensors for selective detection of Hg²⁺ over a range of metal ions. More interestingly, after addition of NO₃^– and ClO₄^– SNT‐ 1 was observed to change color from yellow to violet and pink, respectively. However, no color changes were observed upon addition of Cl^–, Br^–, I^–, SCN^–, or SO₄^2–. Furthermore, the extraction ability of SNT‐ 1 was also estimated by measuring the amount of Hg²⁺ adsorbed by ion chromatography, showing that 95 % of the Hg²⁺ ion is extracted by SNT‐ 1 . This suggests that SNT‐ 1 is potentially useful as a stationary phase for the separation of Hg²⁺ in liquid chromatography. In order to extend the above performance to a portable chemosensor kit, SNT‐ 1 was coated as a thin film of 50 μm thickness onto a glass substrate. The supported SNT‐ 1 also changed from yellow to violet when dipped into Hg²⁺ solution. On the other hand, no significant change in color was observed in other metal‐ion solutions. The results imply that the supported SNT‐ 1 is applicable as a portable colorimetric sensor for detection of Hg²⁺ in the field.     

H2xMnxSn3‐xS6 (x = 0.11–0.25): A Novel Reusable Sorbent for Highly Specific Mercury Capture Under Extreme pH Conditions

The H_2xMn_xSn_3‐xS₆ (x = 0.11–0.25) is a new solid acid with a layered hydrogen metal sulfide (LHMS). It derives from K_2xMn_xSn_3–xS₆ (x = 0.5–0.95) (KMS‐1) upon treating it with highly acidic solutions. We demonstrate that LHMS‐1 has enormous affinity for the very soft metal ions such as Hg²⁺ and Ag⁺ which occurs via a rapid ion exchange process. The tremendous affinity of LHMS‐1 for Hg²⁺ is reflected in very high distribution coefficient K_d^Hg values (>10⁶ mL g^?1). The large affinity and selectivity of LHMS‐1 for Hg²⁺ persists in a very wide pH range (from less than zero to nine) and even in the presence of highly concentrated HCl and HNO₃ acids. LHMS‐1 is significantly more selective for Hg²⁺ and Ag⁺ than for the less soft cations Pb²⁺ and Cd²⁺. The Hg²⁺ ions are immobilized in octahedral sites between the sulfide layers of the materials via Hg–S bonds as suggested by pair distribution function (PDF) analysis. LHMS‐1 could decrease trace concentrations of Hg²⁺ (e.g. <100 ppb) to well below the acceptable limits for the drinking water in less than two min. Hg‐laden LHMS‐1 shows a remarkable hydrothermal stability and resistance in 6 M HCl solutions. LHMS‐1 could be regenerated by treating Hg‐loaded samples with 12 M HCl and re‐used without loss of its initial exchange capacity.     

An Alternative Copolymer of Carbazole and Thieno[3,4b]‐Pyrazine: Synthesis and Mercury Detection

A donor‐π‐acceptor (D‐π‐A) alternative copolymer of carbazole and thieno[3,4b]‐pyrazine [P(CZ‐TPZ)] is synthesized through a Wittig–Horner reaction. In dilute THF solution, the absorption spectrum of P(CZ‐TPZ) shows two absorption peaks at 306 and 452 nm, respectively, and the PL spectrum of the polymer solution displays a PL peak maximum at 543 nm. The polymer possesses relatively high sensitivity and selectivity for Hg²⁺ detection. Upon addition of Hg²⁺ into its THF solution (containing 0.3% CH₃CN), P(CZ‐TPZ) exhibits a new absorption peak at 560～600 nm and its emission was quenched dramatically. The Hg²⁺ detection shows high selectivity in comparison with the other cations of Na⁺, K⁺, Mg²⁺, Ba²⁺, Al³⁺, Cu²⁺, Cd²⁺, Pb²⁺, Ni²⁺, Mn²⁺, and Co²⁺. The Hg²⁺ detection limit of the polymer solution by emission quenching is found to be 1 × 10^?7 mol L^?1. P(CZ‐TPZ) also shows a selective chromogenic behavior toward Hg²⁺ with color change of the solution from yellow to blue dark which can be detected with the naked eye, the detection limit reaches 1 × 10^?6 mol L^?1 with a 1 × 10^?4 mol L^?1 polymer solution. The absorption and PL spectral change can be resumed after adding thiourea, therefore the sensing ability of the polymer is re‐usable with the treatment of thiourea. The results indicate that P(CZ‐TPZ) is a promising chemosensor for the Hg²⁺ detection.     

Double Stimuli‐Responsive Isoporous Membranes via Post‐Modification of pH‐Sensitive Self‐Assembled Diblock Copolymer Membranes

Double stimuli‐responsive membranes are prepared by modification of pH‐sensitive integral asymmetric polystyrene‐b‐poly(4‐vinylpyridine) (PS‐b‐P4VP) diblock copolymer membranes with temperature‐responsive poly(N‐isopropylacrylamide) (pNIPAM) by a surface linking reaction. PS‐b‐P4VP membranes are first functionalized with a mild mussel‐inspired polydopamine coating and then reacted via Michael addition with an amine‐terminated pNIPAM‐NH₂ under slightly basic conditions. The membranes are thoroughly characterized by nuclear magnetic resonance (¹H‐NMR), Fourier transform infrared spectroscopy and X‐ray‐induced photoelectron spectroscopy. Additionally dynamic contact angle measurements are performed comparing the sinking rate of water droplets at different temperatures. The pH‐ and thermo‐double sensitivities of the modified membranes are proven by determining the water flux under different temperature and pH conditions.     

Functionalized Cubic Mesoporous Silica as a Non‐Chemodosimetric Fluorescence Probe and Adsorbent for Selective Detection and Removal of Bisulfite Anions along with Toxic Metal Ions

Dual signaling and remediation systems for detection and adsorption of toxic analytes have gained more attention over sensory probes only. However, most of the sensors for bisulfites are chemodosimetric probes, which are irreversible and having drawbacks of absolute selectivity, recyclability, and solubility in a pure aqueous system. To address above drawbacks a new non‐chemodosimetric probe material with a strong hydrogen bonding pocket for bisulfites is developed. Synthesis of cubic mesoporous silica by a modified Stober process followed by functionalization with 2,2′‐(((((3‐(triethoxysilyl)propyl)azanediyl)bis(methylene))bis(2,1‐phenylene))bis(oxy))bis(N‐(4‐((E)‐phenyldiazenyl)phenyl)acetamide) (AZOL) has given a fluorogenic silica probe material SiO₂@AZOL. This material shows selectivity toward bisulfite anion (limit of detection (LOD): 64 ppb) and Hg²⁺, Cd²⁺, Cu²⁺, and Zn²⁺ cations (LOD: 126, 95, 14, and 27 ppb, respectively) among various analytes. The adsorption studies for these toxic analytes (HSO₃ ^?, Hg²⁺, Cd²⁺, Cu²⁺, and Zn²⁺) show an extraction efficiency of around 99% and adsorption capacities of 873, 630, 633, 260, and 412 mg g^?1, respectively. Spectroscopic studies along with adsorption, striping, and regeneration studies reveal that this material is a recyclable sensory cum adsorbent material for these toxic analytes. Moreover, this material can be used as a sensitive probe material for determination of HSO₃ ^? levels in various sugar samples.     

Solar Cells with Enhanced Photocurrent Efficiencies Using Oligoaniline‐Crosslinked Au/CdS Nanoparticles Arrays on Electrodes

Different configurations of CdS nanoparticles (NPs) are linked to Au electrodes by electropolymerization of thioaniline‐functionalized CdS NPs onto thioaniline‐functionalized Au‐electrodes. In one configuration, thioaniline‐functionalized CdS NPs are electropolymerized in the presence of thioanline‐modified Au NPs to yield an oligoaniline‐crosslinked CdS/Au NPs array. The NP‐functionalized electrode generates a photocurrent with a quantum yield that corresponds to ca. 9%. The photocurrent intensities are controlled by the potential applied on the electrode, and the redox‐state of the oligoaniline bridge. In the oxidized quinoide state of the oligoaniline units, the bridges act as electron acceptors that trap the conduction‐band electrons that are transported to the electrode and lead to high quantum yield photocurrents. The reduced π‐donor oligoaniline bridges act as π‐donor sites that associate N,N′‐dimethyl‐4,4′‐bipyridinium, MV²⁺, by donor/acceptor interactions, K_a = 5270 M^?1. The associated MV²⁺ acts as an effective trap of the conduction‐band electrons, and in the presence of triethanolamine (TEOA) as an electron donor, high photocurrent values are measured (ca. 12% quantum yield). The electropolymerization of thioaniline‐functionalized Au NPs and thioaniline‐modified CdS NPs in the presence of MV²⁺ yields a MV²⁺‐imprinted NP array. The imprinted array exhibits enhanced affinities toward the association of MV²⁺ to the oligoaniline π‐donor sites, K_a = 2.29 × 10⁴ M^?1. This results in the effective trapping of the conduction‐band electrons and an enhanced quantum yield of the photocurrent, ca. 34%. The sacrificial electron donor, TEOA, was substituted with the reversible donor I₃^?. A solar cell consisting of the imprinted CdS/Au NPs array, with MV²⁺ and I₃^?, was constructed. The cell generated a photocurrent with a quantum yield of 4.7%.     

Selective Zinc(II)‐Ion Fluorescence Sensing by a Functionalized Mesoporous Material Covalently Grafted with a Fluorescent Chromophore and Consequent Biological Applications

A highly ordered 2D‐hexagonal mesoporous silica material is functionalized with 3‐aminopropyltriethoxysilane. This organically modified mesoporous material is grafted with a dialdehyde fluorescent chromophore, 4‐methyl‐2,6‐diformyl phenol. Powder X‐ray diffraction, transmission electron microscopy, N₂ sorption, Fourier transform infrared spectroscopy, and UV‐visible absorption and emission have been employed to characterize the material. This material shows excellent selective Zn²⁺ sensing, which is due to the fluorophore moiety present at its surface. Fluorescence measurements reveal that the emission intensity of the Zn²⁺‐bound mesoporous material increases significantly upon addition of various concentrations of Zn²⁺, while the introduction of other biologically relevant (Ca²⁺, Mg²⁺, Na⁺, and K⁺) and environmentally hazardous transition‐metal ions results in either unchanged or weakened intensity. The enhancement of fluorescence is attributed to the strong covalent binding of Zn²⁺, evident from the large binding constant value (0.87 × 10⁴ M ^?1). Thus, this functionalized mesoporous material grafted with the fluorescent chromophore could monitor or recognize Zn²⁺ from a mixture of ions that contains Zn²⁺ even in trace amounts and can be considered as a selective fluorescent probe. We have examined the application of this mesoporous zinc(II) sensor to cultured living cells (A375 human melanoma and human cervical cancer cell, HeLa) by fluorescence microscopy.     

Anisotropic Ag2S–Au Triangular Nanoprisms with Desired Configuration for Plasmonic Photocatalytic Hydrogen Generation in Visible/Near‐Infrared Region

Anisotropic Ag₂S‐edged Au‐triangular nanoprisms (TNPs) are constructed by controlling preferential overgrowth of Ag₂S as plasmonic photocatalysts for hydrogen generation. Under visible and near‐infrared light irradiation, Ag₂S‐edged Au‐TNPs exhibit almost fourfold higher efficiency (796 µmol h⁻¹ g⁻¹) than those of Ag₂S‐covered Au‐TNPs (216 µmol h⁻¹ g⁻¹) and pure Au‐TNPs in hydrogen generation. A single‐particle photoluminescence study demonstrates that the plasmon‐induced hot electrons transfer from Au‐TNPs to Ag₂S for hydrogen generation. Finite‐difference‐time‐domain simulations verify that the corners/edges of Au‐TNPs are high‐curvature sites with maximum electric field distributions facilitating hot electron generation and transfer. Therefore, Ag₂S‐edged Au‐TNPs are efficient plasmonic photocatalyst with the desired configurations for charge separation boosting hydrogen generation.     

Ultrasensitive Detection of a Variety of Analytical Targets Based on a Functionalized Low‐Resistance AuNPs/β‐Ni(OH)2 Nanosheets/Ni Foam Sensing Platform

Simple, low‐cost and yet accurate, sensitive, and quantitative detection of a broad range of analytical targets by means of small footprint sensing devices has the potential to revolutionize medical diagnostics, food safety, and environmental monitoring. This work demonstrates a functional nucleic acids (FNAs) tethered AuNPs/β‐Ni(OH)₂ nanosheets (NS)/Ni foam nanocomposite as a miniaturized electrode. Through the rational design of a low‐barrier ohmic contact of AuNPs to β‐Ni(OH)₂ NS and a target mediated nanochannel electron transfer effect, a variety of analytical targets, ranging from a disease marker (thrombin, 16.3 × 10^?12 m detection limit) to an important biological cofactor (adenosine, 3.2 × 10^?12 m detection limit), and to a toxic metal ion (Hg²⁺, 3.1 × 10^?12 m detection limit), are detected with ultrasensitivity. The presence of target triggers the conformational change of FNAs, introducing strong steric hindrance and electrostatic repulsion to the diffusion of electron indicators toward the electrode surface, ultimately leading to the changes in impedance. A novel equivalent circuit considering the capacitive reactance is proposed to describe the 2D NS‐based impedance DNA bioelectrode. This sensing platform is easily applicable to the detection of many other targets in diverse sample matrices through the use of other suitable FNAs materials.     

High‐Security Nanocluster for Switching Photodynamic Combining Photothermal and Acid‐Induced Drug Compliance Therapy Guided by Multimodal Active‐Targeting Imaging

High‐security nanoplatform with enhanced therapy compliance is extremely promising for tumor. Herein, using a simple and high‐efficient self‐assembly method, a novel active‐targeting nanocluster probe, namely, Ag₂S/chlorin e6 (Ce6)/DOX@DSPE‐mPEG₂₀₀₀‐folate (ACD‐FA) is synthesized. Experiments indicate that ACD‐FA is capable of specifically labeling tumor and guiding targeting ablation of the tumor via precise positioning from fluorescence and photoacoustic imaging. Importantly, the probe is endowed with a photodynamic “on‐off” effect, that is, Ag₂S could effectively quench the fluorescence of chlorin e6 (89.5%) and inhibit release of ¹O₂ (92.7%), which is conducive to avoid unwanted phototoxicity during transhipment in the body, and only after nanocluster endocytosed by tumor cells could release Ce6 to produce ¹O₂. Moreover, ACD‐FA also achieves excellent acid‐responsive drug release, and exhibits eminent chemo‐photothermal and photodynamic effects upon laser irradiation. Compared with single or two treatment combining modalities, ACD‐FA could provide the best cancer therapeutic effect with a relatively low dose, because it made the most of combined effect from chemo‐photothermal and controlled photodynamic therapy, and significantly improves the drug compliance. Besides, the active‐targeting nanocluster notably reduces nonspecific toxicity of both doxorubicin and chlorin e6. Together, this study demonstrates the potency of a newly designed nanocluster for nonradioactive concomitant therapy with precise tumor‐targeting capability.     

Multifunctional Poly‐N‐Isopropylacrylamide/DNAzyme Microgels as Highly Efficient and Recyclable Catalysts for Biosensing

The development of highly efficient, recyclable, and multifunctional biocatalysts is of great importance for various applications, especially in biosensing. In this study, highly catalytic and recyclable DNAzyme functionalized poly‐N‐isopropylacrylamide (pNIPAM) microgels are prepared via one‐step precipitation polymerization. The pNIPAM/DNAzyme microgels exhibit highly catalytic activities in aqueous solution at room temperature, and become hydrophobic and separable from the reaction mixture at temperature higher than the lower critical solution temperature of pNIPAM, which facilitate the recyclable utilization of these catalysts. Different kinds of DNAzyme functionalized catalytic microgels can be facilely prepared via the one‐step synthesis procedure. Two typical catalytic DNA structures, the Mg²⁺‐dependent DNAzyme and the hemin‐G‐quadruplex horseradish peroxidase (HRP)‐mimicking DNAzyme, are chosen as model systems to validate the feasibility. These pNIPAM/DNAzyme microgel catalysts maintain 80% to 91% initial catalytic activity after eight times of catalysis recycling. Furthermore, the pNIPAM microgels by themselves provide additional interfaces to capturing an enzyme, glucose oxidase, which can cascade with the linked HRP mimicking DNAzymes, to form recyclable bi‐enzyme cascading system for the sensing of glucose.     

Selective Ion Transport and Complexation in Layer‐by‐Layer Assemblies of p‐Sulfonato‐ calix[n]arenes and Cationic Polyelectrolytes

The first study of ion transport across self‐assembled multilayered films of p‐sulfonato‐calix[n]arenes and poly(vinyl amine) (PVA) is presented. The films are prepared by the alternate electrostatic layer‐by‐layer assembly of the anionic calixarenes and cationic PVA on porous polyacrylonitrile (PAN) supports. We use tetra‐p‐sulfonato‐calix[4]arene (calix4), hexa‐p‐sulfonato‐calix[6]arene (calix6), and octa‐p‐sulfonato‐calix[8]arene (calix8) as the calixarenes. Ultraviolet (UV) studies indicate that dipping solutions of pH 6.8, without a supporting electrolyte, are most suited for film preparation. Calix8 is adsorbed in higher concentrations per layer than calix6 or calix4, probably because desorption is less pronounced. The permeation rates, P_Rs, of monovalent alkali‐metal chlorides (Li, Na, K, Cs), magnesium chloride, divalent transition‐metal chlorides (Ni, Cu, Zn), trivalent lanthanide chlorides (La, Ce, Pr, Sm), and sodium sulfate across the calix4/PVA, calix6/PVA, and calix8/PVA membranes are studied and compared with the corresponding P_R values across a poly(styrene sulfonate) (PSS)/PVA multilayer membrane prepared under the same conditions. The P_R values of the alkali‐metal salts are between 4 and 17 × 10^–6 cm s^–1, those of magnesium chloride and the transition‐metal salts are 0.2–1.3 × 10^–6 cm s^–1, and those of the lanthanide salts are about 0.1 × 10^–6 cm s^–1. Possible origins for the large differences are discussed. Ion transport is first of all controlled by electrostatic effects such as Donnan rejection of di‐ and trivalent ions in the membrane, but metal‐ion complexation with the calixarene derivatives also plays a role. Complexation occurs especially between Li⁺ or Na⁺ and calix4, Mg²⁺, or Cu²⁺ and calix6, Cu²⁺, Zn²⁺, or the lanthanide ions and calix8. Divalent sulfate ions are found to replace the calixarene polyanions in the membrane. UV studies of the permeate solutions indicate that calix4 especially is displaced during sulfate permeation.     

Supramolecular‐Assembled Nanoporous Film with Switchable Metal Salts for a Triboelectric Nanogenerator

A triboelectric nanogenerators (TENG) are of great interest as emerging power harvesters because of their simple device architecture with unprecedented high efficiency. Despite the substantial development of new constituent materials and device architectures, a TENG with a switchable surface on a single device, which allows for facile control of the triboelectric output performance, remains a challenge. Here, a supramolecular route for fabricating a novel TENG based on an alkali‐metal‐bound porous film, where the alkali metal ions are readily switched among one another is demonstrated. The soft nanoporous TENG contains numerous SO₃^? groups on the surface of nanopores prepared from the supramolecular assembly of sulfonic‐acid‐terminated polystyrene and poly(2‐vinylpyridine) (P2VP), followed by soft etching of P2VP. Selective binding of alkali metal ions, including Li⁺, Na⁺, K⁺, and Cs⁺, with SO₃^? groups enables the development of mechanically robust alkali‐metal‐ion‐decorated TENGs. The triboelectric output performance of the devices strongly depends on the alkali metal ion species, and the output power ranges from 11.5 to 256.5 µW. This wide‐range triboelectric tuning can be achieved simply by a conventional ion exchange process in a reversible manner, thereby allowing reversible control of the output performance in a single device platform.     

Reusable Polyacrylonitrile-Sulfur Extractor of Heavy Metal Ions from Wastewater

Mercury, lead, and cadmium are among the most toxic and carcinogenic heavy metal ions (HMIs), posing serious threats to the sustainability of aquatic ecosystems and public health. There is an urgent need to remove these ions from water by a cheap but green process. Traditional methods have insufficient removal efficiency and reusability. Structurally robust, large surface-area adsorbents functionalized with high-selectivity affinity to HMIs are attractive filter materials. Here, an adsorbent prepared by vulcanization of polyacrylonitrile (PAN), a nitrogen-rich polymer, is reported, giving rise to PAN-S nanoparticles with cyclic π-conjugated backbone and electronic conductivity. PAN-S can be coated on ultra-robust melamine (ML) foam by simple dipping and drying. In agreement with hard/soft acid/base theory, N- and S-containing soft Lewis bases have strong binding to Hg²⁺, Pb²⁺, Cu²⁺, and Cd²⁺, with extraordinary capture efficiency and performance stability. Furthermore, the used filters, when collected and electrochemically biased in a recycling bath, can release the HMIs into the bath and electrodeposit on the counter-electrode as metallic Hg⁰, Pb⁰, Cu⁰, and Cd⁰, and the PAN-S@ML filter can then be reused at least 6 times as new. The electronically conductive PAN-S@ML filter can be fabricated cheaply and holds promise for scale-up applications.     

Intelligent Molecular Searcher from Logic Computing Network Based on Eu(III) Functionalized UMOFs for Environmental Monitoring

By taking advantage of facile preparation and sensitive recognition capacity, the first example of a fluorescence system based on Eu(III) functionalized UiO(bpdc) (UMOFs) has been constructed for effective combination of ions recognition and logic computing. All the ions, including Hg²⁺, Ag⁺, and S^2? in the system are water harmful, which can be recognized through affecting energy transfer or framework structure. By the self‐assembling, competing and connecting with each other, Eu(III)@UMOFs and the ions have achieved the implementation of Boolean logic network system connecting the elementary logic operations (NOR, INH, and IMP) and integrative logic operation (OR + INH), also obtaining computing keypad‐lock security system by sequential logic operation. To deal with uncertain information in the analog region of nonlinear response (fluorescence and concentration), soft computation through the formulation of fuzzy logic operation has been constructed. On the basis of Boolean logic and fuzzy logic, one intelligent molecular searcher can be realized by taking chemical events (Hg²⁺, Ag⁺, and S^2?) as programmable words and chemical interactions as syntax. Considering the particularity of all the input ions, the approach is helpful in developing the advanced logic program based on Eu(III)@UMOFs for application in environmental monitoring.     

Hydrothermally Stable Thioether‐Bridged Mesoporous Materials with Void Defects in the Pore Walls

Hydrothermally stable thioether‐bridged mesoporous materials have been synthesized by one‐step co‐condensation of 1,4‐bis(triethoxysily)propane tetrasulfide (TESPTS) with tetramethoxysilane (TMOS) using cetyltrimethylammonimum bromide (CTAB) as the surfactant in basic conditions. The ordered mesoporous materials can be formed with a wide range of thioether concentrations in the mesoporous framework, as is seen by X‐ray diffraction (XRD) characterization. The results of N₂ sorption and transmission electron microscopy (TEM) reveal that the materials synthesized with TESPTS/TMOS molar ratios in the range 1:8–1:3 have extensive structural defect holes in the nanochannels. All materials exhibit enhanced hydrothermal stability, which is in proportion to the concentration of thioether bridging in the mesoporous framework. The thioether‐functionalized mesoporous materials are efficient adsorbents for removing Hg²⁺ and phenol from waste water. The Hg²⁺‐adsorption capacity of the material can be as high as 1500 mg g^–1.     

Hybrid CuTCNQ/AgTCNQ Metal‐Organic Charge Transfer Complexes via Galvanic Replacement vs Corrosion‐Recrystallization

This study reports a hybrid of two metal‐organic semiconductors that are based on organic charge transfer complexes of 7,7,8,8‐tetracyanoquinodimethane (TCNQ). It is shown that the spontaneous reaction between semiconducting microrods of CuTCNQ with Ag⁺ ions leads to the formation of a CuTCNQ/AgTCNQ hybrid, both in aqueous solution and acetonitrile, albeit with completely different reaction mechanisms. In an aqueous environment, the reaction proceeds by a complex galvanic replacement (GR) mechanism, wherein in addition to AgTCNQ nanowires, Ag⁰ nanoparticles and Cu(OH)₂ crystals decorate the surface of CuTCNQ microrods. Conversely, in acetonitrile, a GR mechanism is found to be thermodynamically unfavorable and instead a corrosion‐recrystallization mechanism leads to the decoration of CuTCNQ microrods with AgTCNQ nanoplates, resulting in a pure CuTCNQ/AgTCNQ hybrid metal‐organic charge transfer complex. While hybrids of two different inorganic semiconductors are regularly reported, this report pioneers the formation of a hybrid involving two metal‐organic semiconductors that will expand the scope of TCNQ‐based charge transfer complexes for improved catalysis, sensing, electronics, and biological applications.     

Manipulating Charge‐Transfer Character with Electron‐Withdrawing Main‐Group Moieties for the Color Tuning of Iridium Electrophosphors

A new and synthetically versatile strategy has been developed for the phosphorescence color tuning of cyclometalated iridium phosphors by simple tailoring of the phenyl ring of ppy (Hppy = 2‐phenylpyridine) with various main‐group moieties in [Ir(ppy‐X)₂(acac)] (X = B(Mes)₂, SiPh₃, GePh₃, NPh₂, POPh₂, OPh, SPh, SO₂Ph). This can be achieved by shifting the charge‐transfer character from the pyridyl groups in some traditional iridium ppy‐type complexes to the electron‐withdrawing main‐group moieties and these assignments were supported by theoretical calculations. This new color tuning strategy in Ir^III‐based triplet emitters using electron‐withdrawing main‐group moieties provides access to Ir^III phosphors with improved electron injection/electron transporting features essential for highly efficient, color‐switchable organic light‐emitting diodes (OLEDs). The present work furnished OLED colors spanning from bluish‐green to red (505–609 nm) with high electroluminescence efficiencies which have great potential for application in multicolor displays. The maximum external quantum efficiency of 9.4%, luminance efficiency of 10.3 cd A⁻¹ and power efficiency of 5.0 lm W⁻¹ for the red OLED (X = B(Mes)₂), 11.1%, 35.0 cd A⁻¹, and 26.8 lm W⁻¹ for the bluish‐green device (X = OPh), 10.3%, 36.9 cd A⁻¹, and 28.6 lm W⁻¹ for the bright green device (X = NPh₂) as well as 10.7%, 35.1 cd A⁻¹, and 23.1 lm W⁻¹ for the yellow‐emitting device (X = SO₂Ph) can be obtained.