catena-Poly[[(2,2′-bipyidine-2κ2 N,N′)-μ-cyanido-1:2κ2 N:C-dicopper(I)]-μ-bromido-[(2,2′-bipyidine-2κ2 N,N′)-μ-cyanido-1:2κ2 N:C-dicopper(I)]-μ-cyanido-κ2 N:C]

In the title complex, [Cu4Br(CN)3(C10H8N2)2]n, the four independent CuI atoms are all in distorted trigonal-planar geometries. One is formed by one N atom and one C atom from two cyanide groups and one Br atom, one is formed by two N atoms from two cyanide groups and one Br atom, and the other two are formed by two N atoms from a chelating 2,2′-bipyridine (bpy) ligand and one C atom from a cyanide group. The structure exhibits a zigzag chain backbone along [101] constructed by bromide and cyanide anions bridging the CuI atoms, with the [Cu(bpy)(CN)] units pointing laterally

Thermal Stability, Combustion Behavior, and Mechanical Property in a Flame-Retardant Polypropylene System

In order to comprehensively improve the strength, toughness, flame retardancy, smoke suppression, and thermal stability of polypropylene (PP), layered double hydroxide (LDH) Ni0.2Mg2.8Al–LDH was synthesized by a coprecipitation method coupled with the microwave-hydrothermal treatment. The X-ray diffraction (XRD), morphology, mechanical, thermal, and fire properties for PP composites containing 1 wt %–20 wt % Ni0.2Mg2.8Al–LDH were investigated. The cone calorimeter tests confirm that the peak heat release rate (pk–HRR) of PP–20%LDH was decreased to 500 kW/m2 from the 1057 kW/m2 of PP. The pk–HRR, average mass loss rate (AMLR) and effective heat of combustion (EHC) analysis indicates that the condensed phase fire retardant mechanism of Ni0.2Mg2.8Al–LDH in the composites. The production rate and mean release yield of CO for composites gradually decrease as Ni0.2Mg2.8Al–LDH increases in the PP matrix. Thermal analysis indicates that the decomposition temperature for PP–5%LDH and PP–10%LDH is 34 °C higher than that of the pure PP. The mechanical tests reveal that the tensile strength of PP–1%LDH is 7.9 MPa higher than that of the pure PP. Furthermore, the elongation at break of PP–10%LDH is 361% higher than PP. In this work, the synthetic LDH Ni0.2Mg2.8Al–LDH can be used as a flame retardant, smoke suppressant, thermal stabilizer, reinforcing, and toughening agent of PP products

A multifunctional organic-inorganic multilayer film based on tris(1,10-phenanthroline)ruthenium and polyoxometalate

Abstract The novel multifunctional thin films composed of transition metal complex tris(1,10-phenanthroline)ruthenium(II) Ru(phen) 3 Cl 2 (abbr Ru(phen) 3 , phen = 1,10-phenanthroline), and Dawson-type polyoxometalate [P 2 Mo 18 O 62 ] 6− (abbr P 2 Mo 18 ) were fabricated on quartz, silicon and ITO substrates by layer-by-layer (LBL) method. The LBL films deposition were found to be linearly related to the number of bilayers as monitored by UV-vis spectroscopy. And the compositions of the films were measured by X-ray photoelectron spectra (XPS). The result of atomic force microscopy (AFM) revealed a relatively uniform surface morphology of the multilayer films. In particular, the films exhibited the photo-luminescence arising from * -t 2g ligand-to-metal transition of Ru(phen) 3 and catalytic activity to the reduction of NO 2 − attributing to molybdenum-centered redox processes of P 2 Mo 18

Study on controlling factors and developing a quantitative assessment model for spontaneous combustion hazard of coal gangue

Developing a quantitative hazard assessment model for spontaneous coal gangue combustion is imperative to ensuring the safety of coal mining operations. In this study, eight types of coal gangue from different coalfields were used to determine the controlling factors for spontaneous combustion. A variety of physical and chemical characterization methods were employed to investigate the physical and chemical characteristics of the samples. Based on the experimental results, six key parameters were identified, namely the aliphatic C–H components, pyrite sulfur content, physical oxygen absorption capacity, ash content, ignition point temperature, and activation energy for thermal decomposition. The results show that the spontaneous combustion hazard of coal gangue is positively correlated with the first three of these and is negatively correlated with the rest. Using the entropy-weight method combined with the analytic hierarchy process, appropriate weighting factors for each parameter were obtained and used to establish a quantitative assessment model for the spontaneous combustion hazard of coal gangue. This model is expected to enhance the current industrial best practices for the prevention and control of spontaneous coal gangue combustion

Nanomaterial with Core–Shell Structure Composed of {P₂W₁₈O₆₂} and Cobalt Homobenzotrizoate for Supercapacitors and H₂O₂-Sensing Applications

Designing and preparing dual-functional Dawson-type polyoxometalate-based metal–organic framework (POMOF) energy storage materials is challenging. Here, the Dawson-type POMOF nanomaterial with the molecular formula CoK4[P2W18O62]@Co3(btc)2 (abbreviated as {P2W18}@Co-BTC, H3btc = 1,3,5-benzylcarboxylic acid) was prepared using a solid-phase grinding method. XRD, SEM, TEM et al. analyses prove that this nanomaterial has a core–shell structure of Co-BTC wrapping around the {P2W18}. In the three-electrode system, it was found that {P2W18}@Co-BTC has the best supercapacitance performance, with a specific capacitance of 490.7 F g−1 (1 A g−1) and good stability, compared to nanomaterials synthesized with different feedstock ratios and two precursors. In the symmetrical double-electrode system, both the power density (800.00 W kg−1) and the energy density (11.36 Wh kg−1) are greater. In addition, as the electrode material for the H2O2 sensor, {P2W18}@Co-BTC also exhibits a better H2O2-sensing performance, such as a wide linear range (1.9 μM–1.67 mM), low detection limit (0.633 μM), high selectivity, stability (92.4%) and high recovery for the detection of H2O2 in human serum samples. This study provides a new strategy for the development of Dawson-type POMOF nanomaterial compounds