Nanoporous Carbon Derived from Core–Shells@Sheets through the Template-Activation Method for Effective Adsorption of Dyes

A novel template-activation method was used to create nanoporous carbon materials derived from core–shells@rGO sheets. The carbon materials were prepared through an acid etching and thermal activation procedure with three-dimensional Fe₃O₄@C@rGO composites as precursors and Fe₃O₄ nanoparticles as the structural template. The activation at different temperatures could provide materials with different specific surface areas. The unique nanoporous structures with large surface areas are ideal adsorbents. The nanoporous carbon materials were used as adsorbents for the removal of rhodamine B (Rh-B). C@rGO-650 illustrated better adsorption performance than the other synthesized adsorbents. It displayed good recyclability, and its highest adsorption capacity reached up to 14.8 L·g^–1. The remarkable adsorption properties make nanoporous carbon a useful candidate for wastewater treatment. This template-activation method can also broaden the potential applications of core–shells@sheet structures for the construction of nanoporous carbon, which helps to resolve the related energy and environmental issues

Temperature, Cooling Rate, and Additive-Controlled Supramolecular Isomerism in Four Pb(II) Coordination Polymers with an in Situ Ligand Transformation Reaction

Solvothermal reactions of Pb­(Ac)₂ with a new flexible 1,3-bis­(4-pyridyl-3-cyano)­propane (<b>1</b>, BPCP) ligand under different synthesis conditions via an in situ ligand transformation reaction produced three true coordination polymorphs, namely, [PbL^2–]_<i>n</i> (for <b>2</b> and <b>3</b>) and [Pb₃L^2–₃]_<i>n</i> (<b>4</b>), as well as their polymorphic framework [(Pb₂L^2–)·2H₂O]_<i>n</i> (<b>5</b>) (H₂L = 1,3-bis­(4-pyridyl-3-carboxyl)­propane). These compounds were characterized by elemental analysis, IR, TG, PXRD, and single-crystal X-ray diffraction. In these compounds, the L^2–ligand exhibits different coordination conformations and modes tuned by different synthesis conditions, including reaction temperature, cooling rate, and additive, and constructs various architectures by bridging a variety of building units. Polymorphs <b>2</b> and <b>3</b> display a 3D framework with 1D channels built up from dinuclear ringlike [Pb₂L^2–₂] units and dinuclear semi-ring-like [Pb₂L^2–] units, respectively. Polymorph <b>4</b> also features a 3D architecture constructed from dinuclear ringlike [Pb₂L^2–₂] units interlinked by the L^2– ligand. Interestingly, the framework of <b>4</b> is big enough to allow the other net to penetrate to form a 2-fold interpenetrating framework with a trinodal (3,6,10)-connected topology with a point symbol of (4³)­(4⁴·6¹⁰·8)­(4⁸·6²⁴·8⁹·10⁴). For <b>5</b>, there exists two kinds of dinuclear ringlike [Pb₂L^2–₂] units. These [Pb₂L^2–₂] units are interconnected by Pb atoms to afford a 2D undulant network that is further connected by the hydrogen-bonding interactions and weak interactions to afford a 3D supramolecular network. In addition, the photoluminescence properties of <b>1</b>–<b>5</b> and the H₂L ligand in the solid state at room temperature were also investigated

Temperature, Cooling Rate, and Additive-Controlled Supramolecular Isomerism in Four Pb(II) Coordination Polymers with an in Situ Ligand Transformation Reaction

Solvothermal reactions of Pb­(Ac)₂ with a new flexible 1,3-bis­(4-pyridyl-3-cyano)­propane (<b>1</b>, BPCP) ligand under different synthesis conditions via an in situ ligand transformation reaction produced three true coordination polymorphs, namely, [PbL^2–]_<i>n</i> (for <b>2</b> and <b>3</b>) and [Pb₃L^2–₃]_<i>n</i> (<b>4</b>), as well as their polymorphic framework [(Pb₂L^2–)·2H₂O]_<i>n</i> (<b>5</b>) (H₂L = 1,3-bis­(4-pyridyl-3-carboxyl)­propane). These compounds were characterized by elemental analysis, IR, TG, PXRD, and single-crystal X-ray diffraction. In these compounds, the L^2–ligand exhibits different coordination conformations and modes tuned by different synthesis conditions, including reaction temperature, cooling rate, and additive, and constructs various architectures by bridging a variety of building units. Polymorphs <b>2</b> and <b>3</b> display a 3D framework with 1D channels built up from dinuclear ringlike [Pb₂L^2–₂] units and dinuclear semi-ring-like [Pb₂L^2–] units, respectively. Polymorph <b>4</b> also features a 3D architecture constructed from dinuclear ringlike [Pb₂L^2–₂] units interlinked by the L^2– ligand. Interestingly, the framework of <b>4</b> is big enough to allow the other net to penetrate to form a 2-fold interpenetrating framework with a trinodal (3,6,10)-connected topology with a point symbol of (4³)­(4⁴·6¹⁰·8)­(4⁸·6²⁴·8⁹·10⁴). For <b>5</b>, there exists two kinds of dinuclear ringlike [Pb₂L^2–₂] units. These [Pb₂L^2–₂] units are interconnected by Pb atoms to afford a 2D undulant network that is further connected by the hydrogen-bonding interactions and weak interactions to afford a 3D supramolecular network. In addition, the photoluminescence properties of <b>1</b>–<b>5</b> and the H₂L ligand in the solid state at room temperature were also investigated

Systematic Study of the Luminescent Europium-Based Nonanuclear Clusters with Modified 2‑Hydroxybenzophenone Ligands

The reaction of 2-hydroxybenzophenone derivatives with europium ions has afforded a new family of luminescent nonanuclear Eu­(III) clusters. Crystal structure analysis of the clusters reveals that the metal core comprises two vertex-sharing square pyramidal units. Most of these complexes show emissions typical of Eu³⁺ ion under visible light excitation (400–420 nm) at room temperature. Photophysical characterization and DFT study reveal a correlation between luminescent efficiencies of Eu­(III) complexes and the electronic features of the ligands, which can be tuned by the nature of substituents in the 4-position of the ligands. The ligands with a fluorine substituent possess more suitable triplet energy levels, resulting in more intensive luminescence

Systematic Study of the Luminescent Europium-Based Nonanuclear Clusters with Modified 2‑Hydroxybenzophenone Ligands

The reaction of 2-hydroxybenzophenone derivatives with europium ions has afforded a new family of luminescent nonanuclear Eu­(III) clusters. Crystal structure analysis of the clusters reveals that the metal core comprises two vertex-sharing square pyramidal units. Most of these complexes show emissions typical of Eu³⁺ ion under visible light excitation (400–420 nm) at room temperature. Photophysical characterization and DFT study reveal a correlation between luminescent efficiencies of Eu­(III) complexes and the electronic features of the ligands, which can be tuned by the nature of substituents in the 4-position of the ligands. The ligands with a fluorine substituent possess more suitable triplet energy levels, resulting in more intensive luminescence