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The development of efficient and green protocol for recycling of waste plastics is of great significance in terms of “sustainable society” and “green chemistry” concepts. Several ionic liquids (ILs) with different acidity–basicity and structures were one-step synthesized and characterized. They were applied to alcoholysis of polycarbonate (PC) without metal and solvent. The IL structures and reaction conditions were optimized. Moreover, the alcohol scopes and catalyst reusability were evaluated. The results showed that 100% PC conversion and 99% bisphenol A (BPA) yield were obtained by using [HDBU]­[LAc] catalyst, and the [HDBU]­[LAc] could keep high-activity after using for six times under the optimized conditions. Finally, the possible reaction mechanism was proposed via the FT-IR and NMR analysis technique.

Sluggish redox kinetics, shuttle effect, poor conductivity, and large volume change of sulfur limit the practical applications of lithium‐sulfur batteries. Hollow, porous, and necklace‐like Fe3C/N‐codoped carbon nanoboxes (Fe3C/NC) connected by N‐doped carbon (NC) nanofibers are designed by pulverizing Fe2O3 embedded in polyacrylonitrile (PAN) fibers to produce multifunctional sulfur hosts, which exhibit multiple polysulfide anchoring and catalytic conversion activities. Experimental and first‐principles density functional theory studies reveal that the uniformly distributed Fe3C and N units in the nanoboxes can significantly suppress the polysulfide shuttle effect. The conversion of polysulfides (LiPSs) to Li2S is catalyzed during discharge. The process relies on the fast electron transfer through the NC nanofibers and facilitated Li+ diffusion through the porous nanobox shells. The structural characteristics (“boxes in fibers”) of the nanoboxes influence the high sulfur loading and tolerance of volume variation of LiPSs, resulting in the synergistic catalysis of the redox reactions. A high capacity of 645 mAh g−1 after 240 cycles at 1 C, a high capacity of 712 mAh g−1 at a high sulfur loading of 5 mg cm−2 after 100 cycles at 0.2 C, and an enhanced areal capacity of 3.6 mAh cm−2 are demonstrated.

Polyester wastes have caused a series of environmental issues, and it has became imperative to promote recycling of polyester wastes. Herein, a novel protocol for polyester depolymerization to recover the corresponding monomers or chemicals catalyzed by imidazole-anion-derived ionic liquids (ILs) was developed. The catalytic behavior, catalyst recyclability, and versatility for alcoholysis of polyester were studied in detail under mild and green conditions. A comparison of the activity with the reported catalysts was provided, which indicated the unparalleled activity of [HDBU][Im] for the polyester alcoholysis. An in-depth study of the feasible alcoholysis mechanism was given assisting with in situ analysis technique. The developed protocol realized the highly efficient chemical recycling of polyesters via alcoholysis method with unparalleled activity, avoided the pollution caused by toxic transition metal ions and organic solvents, indicating a green and promising alternative for practical recycling of polyester wastes.

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Twelve new metal–organic frameworks (MOFs), namely, [Cd(L)(H2O)] (1), [Cd(L)2Na2]·H2O (2), [Cd(L)(phen)] (3), [Cd(L)(phen)]·2H2O (4), [Cd2(L)2(biim-2)]·H2O (5), [Cd(L)(biim-4)]·2H2O (6), [Co(L)(biim-4)]·H2O (7), [Cd(L)(btp)] (8), [Cd(L)(btb)] (9), [Cd(HL)(bth)0.5(H2O)]·H2O (10), [Co(HL)(btb)0.5]·H2O (11), and [Cd(L)(btbp)1.5]·4H2O (12), where phen = 1,10-phenathroline, biim-2 = 1,2-bis(imidazol-1′-yl)ethane, biim-4 = 1,1′-(1,4-butanediyl)bis(imidazole), btp = 1,3-bis(1,2,4-triazol-1-yl)propane, btb = 1,4-bis(1,2,4-triazol-1-yl)butane, bth = 1,6-bis(1,2,4-triazol-1-yl)hexane, btbp = 4,4′-bis(1,2,4-triazol-1-ylmethyl)biphenyl, and H2L = (3-carboxyl-phenyl)-(4-(2′-carboxyl-phenyl)-benzyl) ether, have been synthesized under hydrothermal conditions. Their structures have been determined by single-crystal X-ray diffraction analyses and further characterized by infrared spectra (IR), elemental analyses, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analyses. Compound 1 features a two-dimensional (2D) layer, which is further stabilized by hydrogen bonds between the coordinated water molecules and adjacent carboxylate oxygen atoms. Compound 2 shows a 2D double layer with 36·46·53 topology. Compounds 3 and 4 exhibit similar one-dimensional (1D) double chains, which are further extended into 2D supramolecular sheets and three-dimensional (3D) supramolecular frameworks through π–π interactions between pyridyl rings and phenyl rings, respectively. Compound 5 furnishes a 1D double chain, which is further extended into a 2D supramolecular layer via two kinds of π–π interactions. Compounds 6 and 7 are isostructural and display the same 2D undulated sheets with 44·62 topology. Compound 8 possesses a 2D sheet structure. Compound 9 displays 3D (3,4)-connected frameworks with (4·102)(4·103·122) topology. Compounds 10 and 11 possess similar 1D infinite chains, which are further linked via π–π interactions to generate 2D supramolecular layers. Compound 12 possesses a 2D double layer, which is further extended into a 3D supramolecular architecture through hydrogen-bonding interactions. The structural and topological differences of the 12 compounds indicate that the L anion and N-donor ligands play important roles in the formation of the final framework structures. The thermal behaviors of compounds 1, 3–4, 8–10, and 12 and luminescent properties of 1–6, 8–10, and 12 have also been investigated in detail.

Four unusual isomorphous metal−organic frameworks, [M 2 (L1)(L2) 2 ] (M = Co for 1, Mn for 2, Zn for 3, and Cd for 4), where H 4 L1 = tetrakis[4-(carboxyphenyl)-oxamethyl]methane acid and L2 = 4-tolyl-2,2′:6′,2″-terpyridine, have been synthesized under hydrothermal conditions. Their structures have been determined by single-crystal X-ray diffraction analyses and further characterized by infrared spectra, elemental analyses, powder X-ray diffraction, UV−vis absorption spectra, and optical energy gaps. In compounds 1−4, the metal atoms are linked by the L1 anions to yield a chain with a loop. Every loop of each chain is penetrated by two L2 ligand rods belonging to the two nearest chains, resulting in an unusual 1D → 2D interdigitated network. In the 2D interdigitated network, there exist weak π−π interactions between pyridyl groups of L2 ligands. If the π−π interactions are regarded as linkers, the 2D interdigitated network belongs to an uneven (3,4)-connected layer. Furthermore, each individual (3,4)-connected layer is polycatenated with an infinite number of other perpendicular layers, yielding an unusual 2D → 3D polycatenane framework. The luminescent properties of compounds 3 and 4 have been studied. In addition, compounds 1−4 exhibit photocatalytic activities for MB degradation under UV irradiation. Submicrometer fiber 1′ shows high photocatalytic efficiency for MB degradation with respect to its corresponding macroscaled crystalline 1.

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