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Silver-indium-sulfide quantum dots (AIS QDs) have potential applications in many areas, including biomedicine. Their lack of regulated heavy metals, unlike many commercialized QDs, stands out as an advantage, but the necessity for alloyed or core-shell structures and related costly and sophisticated processes for the production of stable and high quantum yield aqueous AIS QDs are the current challenges. The present study demonstrates the one-step aqueous synthesis of simple AgInS2 QD compositions utilizing for the first time either a polyethyleneimine/2-mercaptopropionic acid (AIS-PEI/2MPA) mixture or only 2-mercaptopropionic acid (AIS-2MPA) as the stabilizing molecules, providing a AgInS2 portfolio consisting of cationic and anionic AIS QDs, respectively, and tuneable emission. Small AIS QDs with long-term stability and high quantum yields (19-23%) were achieved at a molar ratio of Ag/In/S 1/10/10 in water without any dopant or a semiconductor shell. The theranostic potential of these cationic and anionic AIS QDs was also evaluated in vitro. Non-toxic doses were determined, and fluorescence imaging potential was demonstrated. More importantly, these QDs were electrostatically loaded with zwitterionic 5-aminolevulinic acid (ALA) as a prodrug to enhance the tumor availability of ALA and to improve ALA-induced porphyrin photodynamic therapy (PDT). This is the first study investigating the influence of nanoparticle charge on ALA binding, release, and therapeutic efficacy. Surface charge was found to be more critical in cellular internalization and dark toxicity rather than drug loading and release. Both QDs provided enhanced ALA release at acidic pH but protected the prodrug at physiological pH, which is critical for tumor delivery of ALA, which suffers from low bioavailability. The PDT efficacy of the ALA-loaded AIS QDs was tested in 2D monolayers and 3D constructs of HT29 and SW480 human colon adenocarcinoma cancer cell lines. The incorporation of ALA delivery by the AIS QDs, which on their own do not cause phototoxicity, elicited significant cell death due to enhanced light-induced ROS generation and apoptotic/necrotic cell death, reducing the IC50 for ALA dramatically to about 0.1 and 0.01 mM in anionic and cationic AIS QDs, respectively. Combined with simple synthetic methods, the strong intracellular photoluminescence of AIS QDs, good biocompatibility of especially the anionic AIS QDs, and the ability to act as drug carriers for effective PDT signify that the AIS QDs, in particular AIS-2MPA, are highly promising theranostic QDs., Newton-Katip Celebi Fund partnership; Research Councils UK; Scientific and Technological Research Council of Turkey (TÜBİTAK)

Tocopherols are natural bioactive compounds with several health benefits. This study evaluated the effect of different ratios of α- and δ- tocopherol homologs to protect sunflower oil (SO) and olive pomace oil (OPO) against oxidation. A synergistic effect was recorded when the two tocopherols were combined at a ratio of 7:1 (α-T/δ-T). The oil samples were exposed to accelerated oxidation conditions using a Rancimat (90 °C and airflow of 15 L/h for 24 h) and protection from tocopherols was compared with that from butylated hydroxytoluene (BHT). Assessment of oil stability was examined using well-known parameters such as peroxide value (PV), thiobarbituric acid reactive substances (TBARS), p-anisidine value (p-AV), conjugated dienes (CD) and trienes (CT), and total oxidation (Totox) value, which were all significantly reduced when tocopherols were added at a ratio of 7:1 α-T/δ-T. Primary oxidative compounds measured according to PV were only reduced in SO samples (6.11%). Off-flavor compounds measured via TBARS assay in SO samples were reduced by above 20%, while p-AV was also reduced. CDvalue was correlated with PV in SO samples, while the 7:1 mixture was more effective than BHT for CTvalue. Total oxidation values in SO samples and OPO samples were reduced by 6.02% and 12.62%, respectively. These values in SO samples also provided a remarkable correlation (R2 > 0.95) with incubation time. Moreover, the synergistic effect was not only effective in reducing the oxidation values of oil samples, but also in lowering the degradation rate of tocopherols. Protective effects from tocopherols were mainly observed in SO samples, as OPO samples were more resistant to oxidation processes. This effect was even observed in fatty acid analysis, where the 7:1 mixture provided better results than BHT-spiked samples. Thus, it is suggested that tocopherol mixtures might be used as a natural preservative in the food industry to restrain lipid oxidation processes.

Here in, ONS-donor atom containing Schiff base ligands (1, 2) was used to prepare 1a and 2a complexes. The Schiff base ligands were synthesized using 2?hydroxy-3-methoxysalicylaldehyde and 4-benzoxybenzaldehyde with methyl 2-amino-6-benzyl-4,5,6,7-tetrahydrothieno[2,3-c]pyridine-3-carboxylate as precursors in ethanol medium. Pd(II) complexes (1a, 2a) were prepared using the corresponding PdCl2(CH3CN)2 and Schiff base in a (1:1) molar proportion. The Schiff bases (1, 2) and their Pd(II) complexes (1a, 2a) were then identified via various analytical/spectroscopic methods (1H and 13C) NMR, UV- Vis spectra, FT-IR, mass, TGA and CHN to determine their molecular structures. Finally, the results obtained based on Suzuki-Miyaura and Mizoroki-Heck cross-coupling reactions show that electron-donating and electron-withdrawing substituents on the aryl halide might produce coupling products in excellent yield in the presence of 1a, 2a complexes (as catalysts) under optimum conditions. © 2022 Muş Alparslan Üniversitesi: BAP-20-TBMY-4902–03 This study was supported by Muş Alparslan University (Turkey) Research Fund (BAP-20-TBMY-4902–03). The authors thank the Institute of Science for their postgraduate studies and the Department of Chemistry of the Faculty of Arts and Sciences of Muş Alparslan University for the characterization of the compounds (FT-IR and UV-Vis Spectrophotometer analysis). This study was supported by Muş Alparslan University (Turkey) Research Fund (BAP-20-TBMY-4902–03). The authors thank the Institute of Science for their postgraduate studies and the Department of Chemistry of the Faculty of Arts and Sciences of Muş Alparslan University for the characterization of the compounds (FT-IR and UV-Vis Spectrophotometer analysis).

Herein we systematically investigated the coordination assembly behavior of Zr4L6 cages with Eu3+ ions at room temperature. Through adjustment of the concentration of Eu salt and changes of the type and molar ratio of the solvent, a series of Zr4L6-Eu structures with different structure dimensionalities have been synthesized and structurally characterized. In addition, we also studied the optical properties of these materials in detail, including the fluorescent and third-order nonlinear-optical properties. Most notably, a 2D layer structure with a strong aromatic π···π-stacking force exhibits a good optical-limiting effect.

A new series of azo chromene dyes were synthesized via a facile cyclocondensation reaction of (E)-1,2-diphenyl-1-diazene and 4-aminocoumarin with 1:2 molar ratio catalyzed by the polyaniline-Fe3O4@ZnO nanocomposite (PANI-Fe3O4@ZnO). The salient features of this protocol lie in simple experimental procedure, moderate reaction conditions, and uses PANI-Fe3O4@ZnO nanocomposite as a magnetically separable heterogeneous catalyst. Two well-known methods were employed for assessing the antioxidant abilities of the target compounds, including free radical trapping of 2,2-diphenyl-1-picrylhydrazyl (DPPH), as well as ferric reducing antioxidant power assay. Also, several synthesized compounds were screened for their in vitro antimicrobial activities by employing the disk diffusion test on Gram-negative as well as Gram-positive bacteria.

A binuclear complex of palladium (Et3NH)2[Pd2(ca)2(μ-Cl)2]·2CH3CN is synthesized by ligand-exchange reaction between [PdCl2(PhCN)2] and (Et3NH)2ca (ca2– = chloranilate) taken in a 1:1 molar ratio. Its crystal structure is determined. Chloranilate ca2– dianion is coordinated to Pd(II) as C-donor bidentate ligand. Using cyclic voltammetry (CV) of the complex in CH3CN, non-reversible oxidation at Ea = 1.58 V and quasi-reversible reduction with Eb = –0.80 V and Ea = –0.54 V (relative to Ag/AgCl) is found. The electron structure of the complex is examined.

Compounds with the general formula $${{{\text{K}}}_{x}}{\text{V}}_{x}^{{{\text{4}} + }}{\text{V}}_{{{\text{2}} - x}}^{{{\text{5}} + }}{{{\text{O}}}_{{\text{5}}}}{\kern 1pt} \cdot {\kern 1pt} n{{{\text{H}}}_{{\text{2}}}}{\text{O}}$$ (0.1 ≤ х ≤ 0.33, 0.2 ≤ n ≤ 0.5) have been synthesized via hydrolytic precipitation using VOSO4·3H2O and HCl. In the presence of hydrated vanadyl sulfate at a KVO3/VOSO4·3H2O molar ratio between 0.1 and 1.0, the process yields $${{{\text{K}}}_{{{\text{0}}{\text{.33}}}}}{\text{V}}_{{{\text{0}}{\text{.33}}}}^{{{\text{4}} + }}{\text{V}}_{{{\text{1}}{\text{.67}}}}^{{{\text{5}} + }}{{{\text{O}}}_{{\text{5}}}}{\kern 1pt} \cdot {\kern 1pt} {\text{0}}.2{{{\text{H}}}_{{\text{2}}}}{\text{O}}{\text{,}}$$ having the highest tetravalent vanadium content. The synthesized compounds have been proposed as electrode materials of all-solid-state ion-selective electrodes. The best performance is offered by an electrode with a $${{{\text{K}}}_{{{\text{0}}{\text{.33}}}}}{\text{V}}_{{{\text{0}}{\text{.33}}}}^{{{\text{4}} + }}{\text{V}}_{{{\text{1}}{\text{.67}}}}^{{{\text{5}} + }}{{{\text{O}}}_{{\text{5}}}}{\kern 1pt} \cdot {\kern 1pt} {\text{0}}.2{{{\text{H}}}_{{\text{2}}}}{\text{O}}$$ based membrane sensitive to potassium cations in the range 1 ≤ $${\text{p}}{{C}_{{{{{\text{K}}}^{ + }}}}}$$ ≤ 4 with a calibration curve slope of 56 mV/ $${\text{p}}{{C}_{{{{{\text{K}}}^{ + }}}}}$$ at 3.6 ≤ рН ≤ 7.0. We have determined the selectivity coefficients of the electrodes for singly, doubly, and triply charged cations.

Cr cation doping in the support of the Ru/CeO2 catalyst with a Cr/Ce molar ratio of 1:9 dramatically improved the CO2 methanation activity at low temperatures, with the turnover frequency value on ...

In this study, calcined layered double hydroxides (ZnAl-cLDH) with Zn/Al molar ratio of 2:1 was prepared via coprecipitation method at constant pH of 9 and calcination at 500 °C. The resultant calc...

The new material [RuGa]@NU-1000 incorporates Ru and Ga in 1.2 and 1.8 wt% respectively (molar ratio 1 : 2). It stems from the grafting of the heterobimetallic ruthenium gallate complex, [MeRu(η6-C6H6)(PPh3)2][GaMe2Cl2] into the MOF material NU-1000. [RuGa]@NU-1000 shows enhanced adsorption of SO2, specially at low pressures (10−3 bar) even when compared with other materials employing more expensive precious metals. Additionally, [RuGa]@NU-1000 samples need not be exposed to such harsh conditions for reactivation as they retain their adsorption properties after several cycles and preserve their porosity and structure. Thus, [RuGa]@NU-1000 is an excellent, selective material suitable for detection and precise quantification of SO2, with a lower cost compared to other MOFs incorporating precious metals.

Researchers have been working on the development of new low temperature catalysts with high NOx conversion, N2 selectivity and resistance to SO2 and H2O in selective catalytic reduction of NOx with NH3 at 120–300 °C. Here, a series of novel FeOx–CeO2–V2O5/TiO2 (FeCeVTi) and MnOx–CeO2–V2O5/TiO2 (MnCeVTi) catalysts were synthesized via a modified solvent-free sol–gel method and their catalytic performances at low temperature were enhanced by doping different contents of Fe or Mn. Among them, the 7%FeCeVTi catalyst (7.0% Ce/Ti and 1.0% V/Ti molar ratio) showed the optimal integrated catalytic performance, whose NOx conversion remained above 92% between 210 and 360 °C and above 86.1% when introducing SO2 for 24 h at 250 °C with nearly 100% N2 selectivity. The interaction among Fe, Ce and V species in FeCeVTi catalysts contributed to their higher Ce3+/Ce4+ and surface V5+ ratio, appropriate redox ability, and more acid sites, which may result in the improvement of their SCR activity and resistance to SO2. The addition of MnOx into the CeVTi system increased the catalytic activity below 235 °C, but largely decreased the N2 selectivity and did not enhance the resistance to SO2 and H2O, which may be due to the too high redox ability of the MnCeVTi catalyst. The NH3-SCR reaction on the CeVTi sample followed the E–R mechanism, and the coexistence of E–R and L–H mechanisms was observed on the FeCeVTi catalyst.

This study investigated the impact of low temperature sulfur exposure prior to hydrothermal aging on the catalytic structure and performance of Cu-SSZ-13 catalyst toward NH3-SCR reaction. The sulfur exposure temperature, duration and the sequence of sulfur exposure vs. hydrothermal aging are investigated. All samples hydrothermally aged in presence of SOx (SO3/SOx = 0.7) have showed decreased activity compared to the sample aged hydrothermally only, but the extent of deactivation varies with different sulfur exposure conditions. The sulfur exposure at 200 °C for 100 hours prior to HTA has the most pronounced impact on the population of active site (Cu) and the SCR performance at low temperatures. And the sample of equivalent thermal and sulfur exposure but with the HTA prior to the sulfur exposure, has less decreases in the active Cu sites and less sulfur stored. In contrast, sulfur exposure at high temperature, e.g. 650 °C, has the least impact on the Cu-SSZ-13 catalyst. The molar ratio of stored sulfur to the decrease amount of active Cu sites is close to 1:1 ratio, which implies the deactivation of sulfur exposed catalyst is mainly due to the decrease of active Cu population. Furthermore, DRIFTs demonstrated that both Z2Cu and ZCuOH sites decrease in most cases and ZCuOH is more impacted compared to Z2Cu. With these findings, we concluded that low temperature sulfur exposure prior to HTA treatment leads to accelerated aging. Further characterization reveals that the aging is mainly due to the decrease in the population of active Cu sites. The finding suggests that a hydrothermal pretreatment before sulfur exposure of Cu-SCR catalyst can retard the deactivation of catalyst to a limited extent in the real-world application.

Photocatalytic CO2 reduction is a highly vital process for converting CO2 into valuable chemicals. However, the reaction always proceeds less efficaciously at low temperature. A combination of optical and thermal conditions is one of the feasible approaches to achieve the reaction with high efficiency and has gained much attention recently. In the present work, we prepared several Co–Cu–Mn trimetallic catalysts via a simple co-precipitation method, which were used in catalyzing photothermal CO2 reduction to hydrocarbons. The metal composition and reduction temperature of the catalysts had important effects on their structural and photoelectrical characteristics and adsorption behaviors, further resulting in diverse catalytic performances. Among the prepared trimetallic catalysts, Co7Cu1Mn1Ox(200), with a Co/Cu/Mn molar ratio of 7/1/1 and reduced at 200 °C in H2 for 2 h, could produce CH4 with an activity of 14.5 mmol gcat−1 h−1 in 10% CO2/30% H2/60% N2, and CH4 and C2+ hydrocarbons with the activities of 15.9 and 7.5 mmol gcat−1 h−1 in 25% CO2/75% H2, respectively. The present strategy for constructing trimetallic oxide catalysts for the photothermal reaction not only provides a highly active catalyst for CO2 utilization, but also offers a potential possibility for reducing the high temperature of conventional thermal reactions.

The incorporation of iron into pristine transition metal oxides has been considered as an effective strategy to enhance the electrocatalytic activity toward oxygen evolution reaction (OER). However...

A new method for controllable supramolecular polymerization based on ABBA type monomer and cucurbit[8]uril monomer through host–guest interaction and photochemistry is reported. The molecular weight and polydispersity of supramolecular polymers can be well controlled by tuning the molar ratio of these host and guest monomers or by tuning the isomer ratio of azobenzene groups in the guest monomers upon the competitive irradiation of lights. This research provides a general methodology for the control of supramolecular polymerization and the structure of supramolecular polymers.

The purpose of this work is to explore the effects of the introduction methods of Ce4+ and Zr4+ on the physicochemical properties, activity, and K tolerance of V2O5-WO3/TiO2 catalyst for the selective catalytic reduction of NOx by NH3. Four different methods, namely pre-impregnation, post-impregnation, co-impregnation, and co-precipitation, were used to synthesize a series of V2O5-WO3-TiO2-CeO2-ZrO2 catalysts. The catalysts were characterized by XRD, BET, NH3-TPD, XPS, and H2-TPR techniques. Moreover, the activity and anti-K poisoning performance were tested by an NH3-SCR model reaction. The results show that the introduction of Ce4+ and Zr4+ can improve the catalytic performance of V2O5-WO3/TiO2 catalyst, but the impregnation method cannot enhance the anti-K poisoning performance. Ce4+ and Zr4+ introduced by co-precipitation method can effectively improve the tolerance of K, which is mainly due to the incorporation of Ce4+ and Zr4+ into TiO2 lattice to form a uniform TiO2-CeO2-ZrO2 solid solution, resulting in the optimal surface acidity and redox performance, and reducing the decreases caused by K-poisoning. Furthermore, based on the best introduction method, we further optimized the molar ratio of Ce4+/Zr4+. It is found that the catalyst exhibits the best anti-K poisoning performance when the molar ratio of Ce4+/Zr4+ is 2:1.

A facile electrochemical method was used for the first-time recovery of an In–Ga–Zn alloy from a spent indium–gallium–zinc oxide (IGZO). In this work, the molar ratio of In, Ga, and Zn in the alloy...

A binary ionic liquid of K[FSA]-[C3C1pyrr][FSA] (2:8 in molar ratio) in which N-methyl-N-propylpyrrolidinium and bis(fluorosulfonyl)amide are abbreviated as [C3C1pyrr] and [FSA], respectively, is a...

A new material, MOF-type [Ir]@NU-1000, was accessed from the incorporation of the iridium organometallic fragment [Ir{κ3(P,Si,Si)PhP(o-C6H4CH2SiiPr2)2}] into NU-1000. The new material incorporates less than 1 wt % of Ir(III) (molar ratio Ir to NU-1000, 1:11), but the heat of adsorption for SO2 is significantly enhanced with respect to that of NU-1000. Being a highly promising adsorbent for SO2 capture, [Ir]@NU-1000 combines exceptional SO2 uptake at room temperature and outstanding cyclability. Additionally, it is stable and can be regenerated after SO2 desorption at low temperature.

Au nanoparticles (NPs) prepared under different molar ratio (concentration) of polyoxometalate Na10SiW9O34 ⋅ 18H2O (SiW9) at definite concentrations of AuIII (0.15 mM), NaOH (1.5 mM), and ascorbic acid (0.225 mM) have been investigated systematically and quantitatively. The size of Au NPs decreases from 81.5 nm to 30.0 nm when the molar ratio of SiW9 increases from 1 to 22, which is related to the activity of Auric precursor in reaction solution. It has been identified that the introduction of SiW9 generates a new complex (expressed as AuIII−SiW9) which is more active than the precursor of Auric hydroxide. Therefore, there is a competing equilibrium between Auric hydroxide and AuIII–SiW9 complex in the reaction system. The increasing AuIII–SiW9 complex results in increasing reaction rate and decreasing Au nanoparticle size, while the increasing Auric hydroxide provides a contrary result. This work represents an approach to tune the size of Au NPs by changing the molar ratio of polyoxometalate SiW9 at a stationary AuIII concentration (0.15 mM) in the ascorbic acid reduction method. The resulting NPs capped by SiW9 are expected a functionalized prospect due to not only the synergism of POM and Au NPs but also the strong coordination ability of POM which makes it continue to be modified.

Long-term high temperature in conventional vanadium extraction process would cause particles to be sintered and wrapped, thus reducing extraction efficiency of vanadium. Based on the purpose of directional conversion and process intensification, this work proposed a combination of low temperature sodium roasting and high efficiency selective oxidation leaching in vanadium extraction. The investigation of the reaction mechanism suggested that the structure of vanadium slag was changed by roasting, which also caused the fracture of spinel. The addition of MnO2 promoted the directional oxidation of low-valent vanadium into high valence. It also found that Na2S2O8 could oxidize low-valent vanadium effectively in leaching. The leaching efficiency of vanadium reached 87.74% under the optimum conditions, including a roasting temperature of 650 °C, a roasting time of 2.0 h, a molar ratio of sodium-to-vanadium of 0.6, a MnO2 (roasting additive) dosage of 5 wt% and a Na2S2O8 (leaching oxidant) dosage of 5 wt%. This percentage is 7.18% higher than that of direct roasting-and-leaching under the same conditions.

Formation conditions were studied for compounds of hydrated vanadium oxide $${{\left( {{\text{N}}{{{\text{H}}}_{{\text{4}}}}} \right)}_{x}}{\text{V}}_{y}^{{{\text{4}} + }}{\text{V}}_{{{\text{2}} - y}}^{{{\text{5}} + }}{{{\text{O}}}_{{\text{5}}}} \cdot n{{{\text{H}}}_{{\text{2}}}}{\text{O}}$$ (0.24 ≤ х ≤ 0.36, 0.24 ≤ y ≤ 0.36) prepared by hydrolytic deposition with vanadyl sulfate used as the acidifier. The compound $${{{\text{(N}}{{{\text{H}}}_{{\text{4}}}}{\text{)}}}_{{{\text{0}}{\text{.36}}}}}{\text{V}}_{{{\text{0}}{\text{.36}}}}^{{{\text{4}} + }}{\text{V}}_{{{\text{1}}{\text{.64}}}}^{{{\text{5}} + }}{{{\text{O}}}_{{\text{5}}}} \cdot {\text{0}}.7{{{\text{H}}}_{{\text{2}}}}{\text{O}}$$ with the highest content of tetravalent vanadium was prepared when the molar ratio is 0.1 ≤ NH4VO3/VOSO4 · 3H2O ≤ 1.0. $${{{\text{(N}}{{{\text{H}}}_{{\text{4}}}}{\text{)}}}_{{{\text{0}}{\text{.1}}}}}{\text{V}}_{{{\text{0}}{\text{.1}}}}^{{{\text{4}} + }}{\text{V}}_{{{\text{1}}{\text{.9}}}}^{{{\text{5}} + }}{{{\text{O}}}_{{\text{5}}}} \cdot {\text{1}}.4{{{\text{H}}}_{{\text{2}}}}{\text{O,}}$$ which has the least content of tetravalent vanadium, was prepared by a sol–gel process combined with ion exchange. The prepared ammoniated compounds based on hydrated vanadium oxide show a potential for use as an active material in solid-phase ion-selective electrodes. The electrodes based on $${{{\text{(N}}{{{\text{H}}}_{{\text{4}}}}{\text{)}}}_{{{\text{0}}{\text{.36}}}}}{\text{V}}_{{{\text{0}}{\text{.36}}}}^{{{\text{4}} + }}{\text{V}}_{{{\text{1}}{\text{.64}}}}^{{{\text{5}} + }}{{{\text{O}}}_{{\text{5}}}} \cdot {\text{0}}.7{{{\text{H}}}_{{\text{2}}}}{\text{O}}$$ and $${{{\text{(N}}{{{\text{H}}}_{{\text{4}}}}{\text{)}}}_{{{\text{0}}{\text{.1}}}}}{\text{V}}_{{{\text{0}}{\text{.1}}}}^{{{\text{4}} + }}{\text{V}}_{{{\text{1}}{\text{.9}}}}^{{{\text{5}} + }}{{{\text{O}}}_{{\text{5}}}} \cdot {\text{1}}.4{{{\text{H}}}_{{\text{2}}}}{\text{O}}$$ are selective toward ammonium cations in the range of concentrations 1 ≤ $${\text{p}}{{C}_{{{\text{NH}}_{{\text{4}}}^{ + }}}}$$ ≤ 4 for working solution acidities of 4 ≤ рH ≤ 7 and 5 ≤ рH ≤ 6 with the slope 55 and 50 $${\text{mV/p}}{{C}_{{{\text{NH}}_{{\text{4}}}^{ + }}}},$$ respectively. Selectivity coefficients in the series of singly, doubly, and triply charged cations were determined for (NH4)xV2O5 · nH2O electrodes.

Lithiation of an imidazole-based monothiolate, 2, by excess n-butyllithium gives a white powder containing both a lithiated product and an nBuLi contaminant (in a ca. 1:1 molar ratio). This white p...

Starting generally with a 4:6:3 molar ratio of Pt, Sn, and R (where R = La–Sm), with or without the application of a NaCl flux, seven ternary compounds were obtained as single crystals. The platinides Pt4Sn6R3 (R = La–Nd) crystallize with the Pt4Ge6Pr3 type of structure (oP52, Pnma, a = 27.6–27.8 Å, b = 4.59–4.64 Å, c = 9.33–9.40 Å). With R = Pr, Pt4Sn6Pr3–x (oP52, Pnma, a = 7.2863(3) Å, b = 4.4909(2) Å, c = 35.114(1) Å) is also obtained, which might be considered a high-temperature polymorph with disorder on the Sn- and Pr-sites. For R = Nd and Sm, a structurally related isostructural series with a slightly different composition Pt3Sn5R2–x (oP52, Cmc21, a = 4.50–4.51 Å, b = 26.14–26.30 Å, c ≈ 7.29 Å) has been observed, together with Pt7Sn9Sm5 (oS42, Amm2, a = 4.3289(5) Å, b = 28.798(4) Å, c = 7.2534(9) Å) under the same conditions. The latter exhibits the rare Zr5Pd9P7-type structure, linking polar intermetallics to metal phosphides, in accord with P7Pd9Zr5≡Pt7Sn9Sm5. All structures may be described in terms of either negative Pt/Sn networks encapsulating positive R atoms, or {PtSnx} clusters (x = 5, 6, or rarely 7) sharing vertices and edges with R in the second coordination sphere and with considerable heterometallic Pt–R bonding contributions., A family of ternary intermetallic compounds has been observed for the light lanthanides from Ce to Eu, with Nd being a transition point. All compounds contain ∼30 at. % Pt but show high variability of the Pt@Snx bonding motifs with the lanthanide size, causing minor compositional and soft structural changes along the series.

To understand the role of alkaline sites played for CO2 methanation and develop better catalysts, the promoted Ni/M0.1Ce0.9Ox catalysts, in which the CeO2 are modified by different alkaline earth metal oxides with a M/Ce (M = Mg, Ca, Sr, Ba) molar ratio of 1/9, have been prepared. With the sol − gel method, different alkaline earth metal oxides present varied distribution states in the modified CeO2 support. MgO and CaO are predominantly dissolved into the CeO2 support lattice to form a pure solid solution structure, while SrO and BaO are dispersed as the carbonates on the CeO2 support surface. The modification of all the alkaline earth metal oxides on CeO2 can improve the intrinsic activity of the obtained supported Ni catalysts, whose activity follows the order of Ni/Ca0.1Ce0.9Ox > Ni/Sr0.1Ce0.9Ox > Ni/Mg0.1Ce0.9Ox > Ni/Ba0.1Ce0.9Ox > Ni/CeO2. H2-TPR, H2 adsorption–desorption and XPS results have revealed that the modification of alkaline earth metal oxides can improve Ni dispersion, induce more surface oxygen vacancies and increase both the amount and the strength of the moderate alkaline sites, which are the major factors determining the activity of the Ni/M0.1Ce0.9Ox catalysts for CO2 methanation. Ni/Ca0.1Ce0.9Ox, possessing the best Ni dispersion and the largest amount of the moderate alkaline sites, displays the highest activity among all the catalysts.

The reaction of divanadium pentoxide and N,N-dimethylformamide under hydrothermal conditions at 180–250°C has been studied. Depending on the temperature and duration (1–7 days) of hydrothermal synthesis, the reaction of V2O5 and (CH3)2N–CHO has been shown to lead to single-phase powders of [(CH3)2NH2]V3O7, VO2(D), and V2O3 in a yield up to 50–85%. Variation of initial pH value of reaction mixtures within 0.5–3.7 and molar ratio V2O5 : (CH3)2N–CHO in the range 1 : 5–1 : 50 provides no considerable effect on the phase composition of synthesis products.

The co-oxidation of As(III) and Fe(II) in acidic solutions by pressured oxygen was studied under an oxygen pressure between 0.5 and 2.0 MPa at a temperature of 150°C. It was confirmed that without Fe(II) ions, As(III) ions in the solutions are virtually non-oxidizable by pressured oxygen even at a temperature as high as 200°C and an oxygen pressure up to 2.0 MPa. Fe(II) ions in the solutions did have a catalysis effect on the oxidation of As(III), possibly attributable to the production of such strong oxidants as hydroxyl free radicals (OH·) and Fe(IV) in the oxidation process of Fe(II). The effects of such factors as the initial molar ratio of Fe(II)/As(III), initial pH value of the solution, oxygen pressure, and the addition of radical scavengers on the oxidation efficiencies of As(III) and Fe(II) were studied. It was found that the oxidation of As(III) was limited in the co-oxidation process due to the accumulation of the As(III) oxidation product, As(V), in the solutions.

CeO2/Co3O4 hybrid nanospheres have been successfully prepared via the thermal decomposition of CeCo-glycolate precursors. The sizes of CeCo-glycolate precursors and also their derived CeO2/Co3O4 nanospheres could be easily tuned by varying the feeding molar ratio of Ce/Co ions. The following heat treatment strongly determines the inner fine structures of CeO2/Co3O4 nanospheres, including the solid and yolk–shell ones. The as-prepared yolk–shell structured CeO2/Co3O4 sample has shown greatly enhanced activity towards catalytic CO oxidation compared to the other catalysts. Moreover, systematic characterization studies have been conducted to disclose the possible reaction pathway that is beneficial for boosting the performance of CeO2/Co3O4 catalysts.

Simultaneous removal of NOx and SO2 by MgO combined with O3 oxidation was studied. The effects of the O3/NO molar ratio, oxidation temperature, and oxidation residence time on N2O5 decomposition and O3 consumption distributions were systematically illustrated, which is of great significance for improving NOx removal efficiency and reducing O3 consumption in practical application. When the O3/NO molar ratio was greater than 1.0, the highest N2O5 yield was achieved at 90 °C. The NOx removal efficiency reached 96.5% at an O3/NO molar ratio of 1.8. The oxidation temperature increased from 90 to 130 °C, resulting in the decrease of N2O5 yield, the improvement of O3-ICC (O3 invalid cycle consumption) caused by N2O5 decomposition, and the decrease of NOx removal efficiency from 96.5 to 76%. Besides, the effects of pH, SO2 concentration, and MgSO3 addition on NOx removal efficiency were also investigated. The results showed that the removal efficiency of NOx decreased with the increase of SO2 concentration, while...

Controlling the growth of metal-organic frameworks (MOFs) at the micro-/nanoscopic scale will result in new physical properties and novel functions into the materials without changing the chemical identities and the characteristic features of the MOFs themselves. Herein, we report a facile approach to synthesize a series of MOFs [Co-MOF, CoxNiy-MOFs (x and y represent the molar ratio of Co2+ and Ni2+ and x/y = 1:1, 1:5, 1:10, 1:15, and 1:20), and Ni-MOF] with a one-dimensional micro-/nanoscaled rod-like architecture. From Co-MOF to CoxNiy-MOFs to Ni-MOF, the diameters of the rods turn to be spindly with the increase of Ni2+ content which will facilitate the supercapacitor performances. Interestingly, Co1Ni20-MOF exhibits a highest specific capacity of 597 F g-1 at 0.5 A g-1 and excellent cycle performance (retained 93.59% after 4000 cycles) among these MOF materials owing to its micro-/nanorod structure with a smaller diameter and the synergy effect between the optimum molar ratio of Co2+ and Ni2+.

A series of imidazolium-based synthetic routes to imidazolium cyclopentadienides are reported. The 2:1 reaction of imidazolium (1) with [Cp2TiIIICl]2 gives [NHCDippH]+[Cp2TiIIICl2]− (NHCDipp = 2,6-diisopropylphenyl-substituted N-heterocyclic carbene) (2). The “inverse sandwich” imidazolium cyclopentadienide (3) is obtained as a crystalline solid via reaction of 1 with both [Cp2TiIIICl]2 and cyclopentadienyllithium (CpLi) (in a molar ratio of 2:1:1) in THF/toluene at elevated temperature. Notably, the 1:1 reaction of 1 with CpLi leads to the isolation of “multidecker” 4 in the solid state, while the corresponding 1:2 reaction of 1 with CpLi gives the crystals of CpLi-bound cyclopentadienyl-imidazolium complex 5. While compounds 3, 4, and 5 have been structurally characterized using single-crystal X-ray diffraction, in solution these complexes dissociate due to the conversion of [NHCDippH]+[Cp]− to both cyclopentadiene and NHCDipp through intramolecular proton transfer. The equilibrium of the acid–base conv...

Metal halide compounds with photovoltaic properties prepared from solution have received increased attention for utilization in solar cells. In this work, low-toxicity cesium bismuth iodides are sy ...

NO removal from flue gas was conducted on a self-made bubbling reactor with ClO2. Results indicated that ClO2 has excellent oxidizing power to NO, and its actual reaction molar ratio is close to the theoretical molar ratio. At the temperature of 80 °C and ClO2/NO = 0.6, the NO removal efficiency can reach 96.7%. The electron spin resonance and inhibitor (sodium formate and isopropanol) addition experiments indicated that the ClO2 and ·OH radical in the solution played an important role in NO oxidation. The mechanism of NO removal by ClO2 was proposed through the analysis of oxidation products and relative references.

The reaction of Sovol (technical mixture of polychlorinated biphenyls) with sodium methoxide in dimethyl sulfoxide and methanol has been studied using the thermodynamic modeling method. The optimal process conditions have been elaborated: 1 atm, 115°C, 0.25 mol of dimethyl sulfoxide, 0.085 mol of methanol, the polychlorinated biphenyls: sodium methoxide molar ratio = 1: 4. Experimental data on the interaction of the polychlorinated biphenyls with sodium methoxide under the theoretically determined conditions have revealed a range of positive effects: savings of the reactants, complete conversion, and the formation of potentially less toxic compounds. The studied interaction can serve as a stage for the pretreatment of toxic polychlorinated biphenyls for the pyrolytic destruction.

The CuO–CeO2/γ-Al2O3 systems have good prospects as catalysts for partial oxidation of dimethyl ether (DME) with air to give hydrogen-rich gas for fuel cell feeding. At atmospheric pressure, temperature of ~350°C, and reaction mixture flow rate of 7 L/(gcat h) and the DME : O2 : N2 molar ratio of 1 : 1 : 4 (DME : air = 1 : 5), the catalysts provide complete DME conversion to hydrogen-rich gas with a low content of CH4 (≤0.8 mol %) and H2 production rate of ~3.1 L/(gcat h).

The reaction of (NHC)ZnEt2 (1) with 2,6-dimethylphenol in the molar ratio 1:2 at room temperature resulted in a monomeric zinc dimethylphenoxide [(NHC)Zn(OC6H3-2,6-Me2)2] (NHC = 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene) (2). Whereas, the reaction of 1 with 2,6-dimethylphenol in the presence of water in the molar ratios 1:2:0.5 or 1:2:1 afforded [(NHC)2Zn2(μ-OH)(μ-OC6H3-2,6-Me2)(OC6H3-2,6-Me2)2] (3) and [(NHC)Zn(μ-OH)(OC6H3-2,6-Me2)]2 (4) respectively. Moreover, reaction of 1 with 2,6-diisopropylphenol in the presence of a base led to the isolation of [(NHC)Zn(μ-OH)(OC6H3-2,6-iPr2)]2 (5). Compounds 2–5 have been fully characterized by spectroscopic and single crystal X-ray diffraction studies. In this paper, we have discussed the synthesis, structural characterizations of 2–5 and the mechanism for the formation of compounds 3–5 from 2.

The influence of the alkali treatment of ZSM-5 zeolites with a silica ratio of 30 within the NaOH : SiO2 molar ratio of 0 : 230, as well as the modification of a ZSM-5 zeolite with phosphorus in the range of 0–8 wt %, on the physicochemical properties and activity in hydrogen transfer reactions in the case of conversion of aliphatic alcohols has been studied. The alkali treatment of the zeolite leads to a decrease in the zeolite silica ratio and a growth in the hydrogen transfer coefficient in the case of transformation of aliphatic alcohols. The modification of the zeolite with phosphorus is equivalent to an increase in the zeolite silica ratio, which leads to a decrease in the hydrogen transfer coefficient.

The effect of ferric ions on cell performance of proton exchange membrane water electrolyzer (PEM WE)was studied by injecting Fe2(SO4)3 solution into DI water to prepare different Fe3+ concentrations contamination (1, 10, 100 parts per million (ppm, molar ratio)). Results showed that there was clear cell performance decay with increasing Fe3+ concentrations, and the cell stopped running at 100 ppm Fe3+ concentration in feed water. With increasing temperature, the cell performance increased for a short period. With low Fe3+ concentrations, cell performance decreased with increasing current density, but with 10 ppm Fe3+ concentration and higher current density of 2A/cm2 , cell performance was enhanced. Therefore, both temperature and current density can make positive contributions to improve cell performance under the condition of contaminated feed water.

In this article, a complex oxidant (CO) composed of NaClO and NaClO2 was employed to remove arsenic from flue gas. Experiments were conducted to evaluate the effects of several influencing parameters on arsenic removal efficiency in a bench-scale reactor, such as molar ratio of NaClO to NaClO2, solution pH, solution temperature and various flue gas components including O2, SO2, NO, CO2. The results indicated that the arsenic removal efficiency could reach 100%, under the optimum experimental conditions, in which molar ratio of NaClO to NaClO2 was 1.0, solution pH was 5.5–6.0, solution temperature was 50 ℃. Besides, it was also observed that O2 and CO2 did not affect the removal of arsenic while both SO2 and NO concentrations in flue gas could significantly inhibit the removal of arsenic. Furthermore, the final reaction products in the solution were analyzed by high-performance liquid chromatography coupled with a hydride-generation atomic fluorescence spectrometer (HPLC-HG-AFS), the reaction mechanism and pathways of arsenic removal using complex absorbent were proposed.

BiOI microparticles with different I/Bi molar ratios were synthesized via a facile coprecipitation method in the absence and presence of EDTA-2Na and were characterized by various techniques. Their activity were evaluated using toxic elemental mercury as model pollutant under fluorescent lamp irradiation. The presence of EDTA-2Na would lead to the production of Bi, facilitating an effective separation of electron and hole pairs due to the transfer of electrons from BiOI surface to Bi. The lower the I/Bi molar ratio, the higher the Hg0 removal efficiency. The superoxide radicals and holes were the main reactive species for enhanced Hg0 removal.

One of the strategic goals in crystal engineering is to synthesize the crystals with predictable structures and valuable properties. Metal Organic Frameworks (MOFs), a new class of crystalline porous materials, is a recent upsurge of interest in materials research. The challenges in the area encompass the deliberate control of structure, and therefore the properties and function, as many synthetic factors play a subtle role in the crystallization of MOFs. Among many influencing factors, nature of solvents, pH, molar ratio of reactants and temperature are four crucial parameters that determine the overall architectures of MOFs. This review presents the effect of these major parameters on the synthesis of several MOFs to clearly understand their influence on the nature of binding and formation of different MOF structures. Keywords: Metal organic frameworks, Influential factors, Solvents, pH, Molar ratio, Temperature

Reactions of the phosphanyl-gold(I) precursor [(AuCl)2(bdppmapy)] (1; bdppmapy = N,N-bis(diphenylphosphanylmethyl)-2-aminopyridine) with Na2S in a 1:1 or 1:2 molar ratio gave rise to one tetradecanuclear and one octanuclear Au(I) sulfido cluster, [Au14S6(bdppmapy)5]Cl2 (2) and [Au18S8(bdppmapy)6]Cl2 (3), respectively. The former displays a new structural framework in gold cluster chemistry. Compounds 2 and 3 showed strong green luminescence and were employed as excellent imaging probes to selectively light up the lysosomes of living cells. Their long-term tracking of lysosomes can be achieved for up to 36 h, while tracking with commercial Lyso-Tracker Red under the same conditions was limited to 3 h. Our work demonstrated the possibility of constructing novel gold(I) sulfido clusters supported by special P-N hybrid ligands and the potential application of these clusters as long-term selective trackers of lysosomes in bioimaging.

The growth mechanism of Ti(C,N) coatings produced by chemical vapor deposition was investigated as a function of the TiCl4/CH3CN molar ratio in excess of H-2. The depositions were carried out at a ...

Although metal–organic frameworks (MOFs) can be extensively used as sacrificial templates to prepare their inorganic counterparts and vice versa, selective generation of these two types of materials in the same synthetic media is seldom involved due to the tremendous difference in composites and their thermodynamic stability. Herein, cobalt layered double hydroxides (Co-LDHs) were successfully prepared at room temperature from a typical synthetic system of zeolitic imidazolate framework-67 (ZIF-67), a methanolic solution of Co2+ and 2-methyimidazole (Hmim). The final products from ZIF-67 to ZIF-67/Co-LDH hybrids to Co-LDHs were easily regulated while gradually increasing the concentration of Co2+ and Hmim or the molar ratio of Co2+/Hmim. There was a similar variation trend in the methanol solvent used as well. The synthetic strategy even can be expanded to the selective synthesis of hetero-bimetallic CoZn-/CoNi-ZIFs and CoZn-/CoNi-LDHs.

Extended contiguous multiple π-coordination (CMπC) bonds play key roles at the molecular interface between extended π-conjugated sp2-carbon frameworks and metal clusters. However, their bond-rearrangement behavior including metal-translocation on an extended sp2-carbon framework has not been well understood. We found that a Pd2 moiety in a bis-tetraene sandwich complex shows metal-translocation either under thermal- or under photo-irradiation conditions, where the molar ratio of the isomers derived from metal-translocation is switchable through interconversion between the thermal equilibrium state and the photo-stationary state. Furthermore, an extended Pd7 chain sandwich complex having extended μ7-CMπC bonds undergoes metal-translocation on a carotene ligand under photo-irradiation conditions.