Jilin University

About: Jilin University is a education organization based out in Changchun, China. It is known for research contribution in the topics: Catalysis & Apoptosis. The organization has 101453 authors who have published 88966 publications receiving 1444456 citations. The organization is also known as: Jílín Dàxué.

Vitrimer Elastomer-Based Jigsaw Puzzle-Like Healable Triboelectric Nanogenerator for Self-Powered Wearable Electronics.

Abstract: Functional polymers possess outstanding uniqueness in fabricating intelligent devices such as sensors and actuators, but they are rarely used for converting mechanical energy into electric power. Here, a vitrimer based triboelectric nanogenerator (VTENG) is developed by embedding a layer of silver nanowire percolation network in a dynamic disulfide bond-based vitrimer elastomer. In virtue of covalent dynamic disulfide bonds in the elastomer matrix, a thermal stimulus enables in situ healing if broken, on demand reconfiguration of shape, and assembly of more sophisticated structures of VTENG devices. On rupture or external damage, the structural integrity and conductivity of VTENG are restored under rapid thermal stimulus. The flexible and stretchable VTENG can be scaled up akin to jigsaw puzzles and transformed from 2D to 3D structures. It is demonstrated that this self-healable and shape-adaptive VTENG can be utilized for mechanical energy harvesters and self-powered tactile/pressure sensors with extended lifetime and excellent design flexibility. These results show that the incorporation of organic materials into electronic devices can not only bestow functional properties but also provide new routes for flexible device fabrication.

A Study of Quantum Confinement Properties of Photogenerated Charges in ZnO Nanoparticles by Surface Photovoltage Spectroscopy

Abstract: The ZnO quantum dots (about 3 nm in average size) and the ZnO nanorods (about 80 nm in length and 14 nm in width) were synthesized by the sol−gel method. They were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), UV−vis spectroscopy, and photoluminescence (PL) spectroscopy. The surface photovoltage (SPV) of ZnO nanoparticles was investigated by means of surface photovoltage spectroscopy (SPS) and field-induced surface photovoltage spectroscopy (FISPS), and the bands were identified. The results show that the SPV of ZnO nanoparticles are greatly different for their different sizes as a result of the quantum confinement effect. The ZnO quantum dots exhibit marked quantum confinement properties; that is, FISPS takes a high symmetry in the changes of the response intensity with the strengthening of the two opposed electric fields, and the FISPS response band always appears at about 369 nm, no matter what external electric field is applied. Whereas for the ZnO nanorods a...

Postsynthetic Functionalization of Three-Dimensional Covalent Organic Frameworks for Selective Extraction of Lanthanide Ions.

Abstract: Chemical functionalization of covalent organic frameworks (COFs) is critical for tuning their properties and broadening their potential applications. However, the introduction of functional groups, especially to three-dimensional (3D) COFs, still remains largely unexplored. Reported here is a general strategy for generating a 3D carboxy-functionalized COF through postsynthetic modification of a hydroxy-functionalized COF, and for the first time exploration of the 3D carboxy-functionalized COF in the selective extraction of lanthanide ions. The obtained COF shows high crystallinity, good chemical stability, and large specific surface area. Furthermore, the carboxy-functionalized COF displays high metal loading capacities together with excellent adsorption selectivity for Nd3+ over Sr2+ and Fe3+ as confirmed by the Langmuir adsorption isotherms and ideal adsorbed solution theory (IAST) calculations. This study not only provides a strategy for versatile functionalization of 3D COFs, but also opens a way to their use in environmentally related applications.

Highly mesoporous single-crystalline zeolite beta synthesized using a nonsurfactant cationic polymer as a dual-function template.

Abstract: Mesoporous zeolites are useful solid catalysts for conversion of bulky molecules because they offer fast mass transfer along with size and shape selectivity. We report here the successful synthesis of mesoporous aluminosilicate zeolite Beta from a commercial cationic polymer that acts as a dual-function template to generate zeolitic micropores and mesopores simultaneously. This is the first demonstration of a single nonsurfactant polymer acting as such a template. Using high-resolution electron microscopy and tomography, we discovered that the resulting material (Beta-MS) has abundant and highly interconnected mesopores. More importantly, we demonstrated using a three-dimensional electron diffraction technique that each Beta-MS particle is a single crystal, whereas most previously reported mesoporous zeolites are comprised of nanosized zeolitic grains with random orientations. The use of nonsurfactant templates is essential to gaining single-crystalline mesoporous zeolites. The single-crystalline nature endows Beta-MS with better hydrothermal stability compared with surfactant-derived mesoporous zeolite Beta. Beta-MS also exhibited remarkably higher catalytic activity than did conventional zeolite Beta in acid-catalyzed reactions involving large molecules.

Synthesis, structure and luminescent properties of rare earth coordination polymers constructed from paddle-wheel building blocks.

Abstract: A series of three-dimensional (3D) novel coordination polymers M(bpdc)1.5(H2O) x 0.5DMF (M = Tb (1), Ho (2), Er (3), or Y (4)) have been synthesized by reaction of the rare earth ions (M3+) with 4,4'-biphenyldicarboxylic acid (H2bpdc) in a mixed solution of DMF and C2H5OH. They possess the same 3D architectures and crystallize in monoclinic space group C2/c. Two seven-coordinated metal centers and four dimonodentate bpdc groups construct a paddle-wheel building block. These building blocks connect with two carboxyl groups to lead to a one-dimensional inorganic chain, ---M-O-C-O-M---, along the [001] direction. The inorganic chains are linked with two biphenyl groups to form 25.15 A x 17.09 A rhombic channels along the c axis without interpenetration. These complexes exhibit strong fluorescence in the visible region, and complex 3 shows Er3+ characteristic emission in the range of 1450-1650 nm at room temperature. These complexes could be anticipated as potential fluorescent probes and an IR-emitter, respectively.