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Promoting the efficient utilization of both pores and heteroatoms remains a highly challenging endeavor, yet is of crucial significance to enhance the specific capacitance and energy density of carbon-based supercapacitors (SCs). Herein, a series of N,P-co-doped polypyrrole-derived carbon nanotubes (Px-ppyNTs) featuring a customized porous structure and doping level and intrinsically endowed with hollow cavities with tunable diameters were designed and synthesized via a strategic engineering approach. Benefiting from their regularly evolved physiochemical architecture, Px-ppyNTs served as a suitable platform to investigate the structure–property relationship between carbon-based materials and electrochemical capacitive behavior. Remarkably, the electrochemical surface area (ECSA) was proven to be critical to the reaction kinetics and resulted in the maximized utilization of both the porous structure and heteroatoms. The optimized ppyNT material with highest utilization of both the SSA (1853 m2 g−1) and inherent heteroatom doping (nitrogen: 7.2 at% and phosphorous: 2.5 at%) exhibited an extremely high specific capacitance of 438 F g−1 in 1.0 M H2SO4 and energy density of 25.3 W h kg−1 in 1.0 M Na2SO4. Furthermore, the calculated electric double layer capacitance (EDLC) contribution was maintained at as high as 203 F g−1 even across a wide scan rate in the range of 5 to 500 mV s−1. This work affords a promising electrode material for SCs and provides new insights into the critical role of ECSA in high-performance carbon-based SCs.

FeSiAl/Al2O3 composites were fabricated by hot-pressed sintering to evaluate the mechanical, dielectric and microwave absorption properties. The results show that the flexural strength of the composites increases with the increase of FeSiAl content, while the density and micro-hardness exhibit a downward tendency. The complex permittivity increases with increasing FeSiAl content in the X-band, which is resulted from the enhanced interfacial polarization, relaxation loss and conductance loss. Meanwhile, a rapid enhancement of complex permittivity for the composite with 10 wt.% FeSiAl is achieved due to the formation of conductive clusters and enhanced conductance loss. By calculating the reflection loss, the composite with 5 wt.% FeSiAl possesses the effective absorption bandwidth (

Two new Cd(II) coordination compounds, namely [Cd(Htci)(biimpy)]n (1) and [Cd3(tci)2(biimpy)2(H2O)2]n (2) (H3tci = tri(2-carboxyethyl)isocyanuric acid, biimpy = 2,6-bis(1-imdazoly)pyridine) were synthesized under solvothermal conditions via tuning the pH of reaction mixture. Single crystal X-ray diffraction analyses revealed that compound 1 features a 2D layer structure that further extended into a 3D supramolecular framework directed by hydrogen bonds, and compound 2 features a 3D pillar-layered framework. In these two compounds, the organic carboxylate ligands adopt two distinct conformations: cis-cis-trans for 1 and cis-cis-cis for 2. The luminescent properties investigations indicated that both 1 and 2 emit intense luminescence at room temperature.

A new Pb(II) coordination polymer, namely [Pb2(bptc)(DMA)]n (1, H4bptc = biphenyl-3,3′,5,5′-tetracarboxylic acid, DMA = N, N′- dimethylacetamide), has been synthesized by the combination of H4bptc with Pb(NO3)2 under solvothermal conditions. Single crystal X-ray diffraction analysis revealed that compound 1 features a 3D framework based on tetranuclear [Pb4(COO)6] subunits, and topological analysis revealed that compound represents a binodal (4, 8)-connected scu-type topological network with the point symbol of {416,612}{44,62}2. Luminescence studies indicated that 1 and 1’ (1′ represents the desolvated samples) showed intense yellow emissions. Significantly, 1′ exhibited sensitive luminescence sensing for CS2 solvent molecules at a low concentration.

Presented here is a new Zn(II) compound, namely [Zn4(btec)2(DMA)3]n (1 represents this compound, H4btec = 1,2,4,5-benzenetetracarboxylic acid, DMA = N,N′-dimethylacetamide). This compound crystallizes in orthorhombic Pbca space group with a = 19.053(2) A, b = 18.8010(6) A, c = 22.9434(8) A, α = β = γ = 90°, and Z = 8. Single crystal X-ray diffraction analysis reveals that compound 1 features a three-dimensional (3D) framework based on two different dinuclear [Zn2(COO)3] subunits. In addition, the solid-state luminescent property of 1 and the gas sorption properties of the desolvated 1a were also investigated.

A new Zn(II) metal–organic framework, namely [Zn3(3-atrz)2(4-atrz)2(SO4)2]n (1 3-atrz = 3-amino-1,2,4-triazole, 4-atrz = 4-amino-1,2,4-triazole), has been solvothermally synthesized via the reactions of ZnSO4·7H2O and two different kinds of isomorphic aminotriazole ligands (3-atrz and 4-atrz). Single crystal X-ray diffraction analysis revealed that compound 1 features a trinuclear [Zn3(3-atrz)2(4-atrz)2(SO4)2] subunits based 3D framework with 6-connected pcu topology. In the 3D framework of 1, 3-atrz ligand displays a μ3-κN1, κN2, κN3 coordination mode and 4-atrz ligand displays a μ2-κN1, κN2 coordination mode. The luminescent properties investigation indicated that compound 1 shows strong luminescence at room temperature and high selectivity and sensitivity for Fe3+ ion in aqueous solution.

A new heterometallic-organic framework, namely [CuCa(tdc)2(DMF)]n (1 H2tdc = 2,5-thiophenedicarboxylic acid, DMF = N,N’-dimethylformamide), has been successfully obtained through the solvothermal reactions of CuCl2, Ca(NO3)2, and H2tdc. Single-crystal structural analysis reveals that compound 1 features a 3D framework with the irl topology. Compound 1 has potential unsaturated metal sites after the removal of the coordinated DMF molecules, so it exhibits excellent catalytic activity for the diethylzinc addition to benzaldehyde.

Via the solvothermal reactions of Cd(NO3)2 and H2L, a new Cd(II) compound, namely [Cd(L)]n (1 H2L = 5-CH2OH-isophthalic acid), was obtained. This compound was further characterized by single-crystal X-ray diffraction analysis, elemental analyses, and powder X-ray diffraction analyses. Single-crystal X-ray diffraction analysis reveals that compound 1 features a 3D framework based on dinuclear [Cd2(COO)2] subunits. Topological analysis reveals that compound 1 represents a new (4, 8)-connected topology. In addition, the luminescent property of 1 was also investigated at room temperature.

A new Cd(II) compound, namely [Cd3(BTC)2(e-urea)4]n (1 H3BTC = 1,3,5-benzenetricarboxylic acid, e-urea = ethylene urea), has been synthesized by the urothermal reactions of 1,3,5-benzenetricarboxylic acid and Cd(NO3)2 and further characterized by elemental analysis, powder X-ray diffraction, and single-crystal X-ray diffraction. Compound 1 features a three-dimensional (3D) framework based on trinuclear [Cd3(COO)6(e-urea)2] subunits. By viewing BTC3−, trinuclear [Cd3(COO)6(e-urea)2] subunits as 3- and 6-connected nodes, respectively, the whole framework of 1 can be simplified into a rtl-type topological network. Moreover, the thermal stability and luminescent property of compound 1 were also investigated.

A new Cd(II) coordination polymer, namely {Cd3(pbdc)3(e-murea)(DMF)}n·n(e-murea) (1, H2pbdc = terephthalic acid, e-murea = 1,3-dimethyl-2-imidazolidinone, DMF = N,N'-dimethylformamide), has been successfully synthesized via the urothermal reactions of Cd(II) ions and terephthalic acid ligand. Single-crystal X-ray structural analysis reveals that 1 features a two-dimensional layer framework with rod-shaped hexanuclear {Cd6(COO)12} clusters as building subunits. In addition, the luminescent property of 1 was also studied at room temperature.

A new Cd(II) coordination polymer, namely [Cd(L)(H2O)]n (1, H2L = 5-(pyridin-3-ylmethoxy)-isophthalic acid), has been synthesized through hydrothermal reactions of Cd(NO3)2 and H2L. The title compound crystallizes in triclinic, space group P-1 with a = 8.450(3), b = 8.941(3), c = 10.057(3) A, α = 70.291(8)°, β = 67.339(10)°, γ = 82.575(11)° V = 660.1(4) A3. Single-crystal X-ray diffraction analysis reveals that compound 1 features a 3D supramolecular framework based on (3,6)-connected 2D sheets.

A new heterometallic poly(dihydrate-one and a half terephthalate–cadmium calcium) coordination polymer, namely [CdCa(pdc)1.5(H2O)2]n (1, H2pdc = terephthalic acid), has been successfully obtained by the solvothermal reactions of H2pdc, Cd(NO3)2·4H2O and Ca(NO3)2·4H2O. Single crystal X-ray diffraction analysis reveals that compound 1 features a 3D porous framework based on 1D chain subunits. Moreover, compound 1 is luminescent and exhibits high adsorption capacities for H2, CH4 and CO2 at room temperature.

Reported here is a new Zn(II) compound, namely [Zn 2 (tdc) 2 (MA)] n (H 2 tdc = 2,5-thiophenedicarboxylic acid, MA = melamine), which has been constructed by the self-assembly reaction of Zn(NO 3 ) 2 , H 2 tdc and MA under solvothermal conditions. Single crystal X-ray diffraction analysis reveals that this compound features a 3D porous framework with 6-connected pcu topology. Notably, this compound exhibits high CO 2 sorption capacity and high sorption selectivity for CO 2 over N 2 at 298 K.

A bio-based Mg(OH)2@tin phytate@zinc tannate (MH@PASn@TAZn) composite was synthesised via layer-by-layer assembly method. Chemical bonds formed by chelating metal ions with phytic acid and tannic acid were involved in this synthesis. MH@PASn@TAZn was then incorporated into PVC and its effects on flame retardancy, smoke suppression and mechanical properties were investigated. The core-shell structure and binding states between each layer (Mg–O–P, P–O–C) of the composite were examined. The limiting oxygen index (LOI) and cone calorimeter test results showed that the addition of 10 ph MH@PASn@TAZn effectively enhanced the flame retardancy and smoke suppression of PVC. The LOI value of the 10 ph MH@PASn@TAZn-incorporated PVC sample increased to 30.3% because of the combination of the gas dilution effect of vapor generated by the degradation of MH and synergistic catalytic carbonisation of PASn and TAZn. The second peak heat release rate, second peak smoke production rate and total smoke production of PVC/MH@PASn@TAZn composite decreased by 40.8%, 72.2% and 35.2%, respectively. The increase in the interfacial contact area of PASn and the enhancement of interfacial interaction of TAZn significantly improved the tensile strength, elongation at break, and impact strength of PVC. This study presents a promising approach to synthesise flame-retardant PVC with excellent smoke suppression and mechanical properties.

Two new Zn(II) compounds, namely [(CH3)2NH2]2n[Zn3(bpt)2(datrz)2]n (1) and [(CH3)2NH2)]n[Zn2(bptc)(datrz)]n·n(H2O) (2) (H3bpt = biphenyl-3,4′,5-tricarboxylic acid, H4bptc = biphenyl-3,3′,5,5′-tetracarboxylic acid, Hdatrz = 3,5-diamino-1,2,4-triazole), have been obtained by the self-assemble reactions of Zn(NO3)2, 3,5-diamino-1,2,4-triazole, aromatic polycarboxylate ligands under solvothermal conditions. Single crystal X-ray structural analyses reveal that both compounds display three-dimensional (3D) frameworks. Compound 1 features a trinodal (3, 4, 6)-connected topological network with the point symbol of {4.62}2{4.64.8}{46.64.85}. Compound 2 displays a binodal (4, 6)-connected topological network with the point symbol of {32.62.72}{34.42.64.75}. In addition, the thermal stabilities and luminescent properties of compounds 1 and 2 were also investigated in the solid state at room temperature.

A new heterometallic compound, namely [CdBa(tdc)2(DMF)2(H2O)]n (1 H2tdc = 2,5-thiophenedicarboxylic acid, DMF = N,N′-dimethylformamide), has been solvothermally synthesized and characterized by elemental analysis and single crystal X-ray diffraction. Compound 1 features a complicated three-dimensional (3D) framework based on heterometallic -{Cd-COO-Ba}n- inorganic chains. In addition, the luminescent properties of this compound were also investigated at room temperature.

Two bromo-substituted Schiff bases 5-bromo-2-methoxy-4-(p-tolyliminomethyl)phenol (1) and 2-bromo-6-[(6-methylpyridin-2-ylimino)methyl]phenol (2) are prepared and characterized by elemental analysis, 1H and 13C NMR, and single crystal X-ray diffraction. Compound 1 crystallizes in the triclinic space group P\(\bar 1\) with unit cell dimensions a = 6.228(1) A, b = 10.929(2) A, c = 21.312(2) A, α = 104.230(2)°, β = 91.780(2)°, γ = 90.890(2)°, V = 1405.0(4) A3, Z = 4, R1 = 0.0359, and wR2 = 0.0830. Compound 2 crystallizes in the monoclinic space group P21/c with unit cell dimensions a = 8.180(2) A, b = 12.011(3) A, c = 12.843(3) A, β = 106.263(2)°, V = 1211.4(4) A3, Z = 4, R1 = 0.0364, and wR2 = 0.0889. X-ray diffraction indicates that the Schiff base molecules of the compounds display trans configuration with respect to the C=N double bonds. The crystal structures of the compounds are stabilized by hydrogen bonds and weak π•••π interactions.

The aroylhydrazone Schiff base ligand [N'-(5-chloro-2-hydroxybenzylidene)-4-hydroxybenzohydrazide (H2L) and salicylhydroxamic acid (Hsha) reacting with VO(acac)2 in methanol gave the complex [VOL(sha)]·3H2O. The complex was characterized by elemental analyses and IR spectroscopic method in the solid state. Single crystal X-ray analysis was performed, which indicated that the complex is a mononuclear compound. The V atom in the complex is in an octahedral geometry. VIV in VO(acac)2 was oxidized to VV in the complex by aerial oxygen during the synthesis and crystallization. Thermal behavior of the complex was studied. Antibacterial activity of the aroylhydrazone ligand and the complex has been studied on the bacteria strains B. subtilis, E. coli, and S. aureus.