Shanghai University

About: Shanghai University is a education organization based out in Shanghai, Shanghai, China. It is known for research contribution in the topics: Microstructure & Catalysis. The organization has 59583 authors who have published 56840 publications receiving 753549 citations. The organization is also known as: Shànghǎi Dàxué.

Sandwich-like SnS2/Graphene/SnS2 with Expanded Interlayer Distance as High-Rate Lithium/Sodium-Ion Battery Anode Materials.

Abstract: SnS2 materials have attracted broad attention in the field of electrochemical energy storage due to their layered structure with high specific capacity. However, the easy restacking property during charge/discharge cycling leads to electrode structure instability and a severe capacity decrease. In this paper, we report a simple one-step hydrothermal synthesis of SnS2/graphene/SnS2 (SnS2/rGO/SnS2) composite with ultrathin SnS2 nanosheets covalently decorated on both sides of reduced graphene oxide sheets via C-S bonds. Owing to the graphene sandwiched between two SnS2 sheets, the composite presents an enlarged interlayer spacing of ∼8.03 A for SnS2, which could facilitate the insertion/extraction of Li+/Na+ ions with rapid transport kinetics as well as inhibit the restacking of SnS2 nanosheets during the charge/discharge cycling. The density functional theory calculation reveals the most stable state of the moderate interlayer spacing for the sandwich-like composite. The diffusion coefficients of Li/Na ions from both molecular simulation and experimental observation also demonstrate that this state is the most suitable for fast ion transport. In addition, numerous ultratiny SnS2 nanoparticles anchored on the graphene sheets can generate dominant pseudocapacitive contribution to the composite especially at large current density, guaranteeing its excellent high-rate performance with 844 and 765 mAh g-1 for Li/Na-ion batteries even at 10 A g-1. No distinct morphology changes occur after 200 cycles, and the SnS2 nanoparticles still recover to a pristine phase without distinct agglomeration, demonstrating that this composite with high-rate capabilities and excellent cycle stability are promising candidates for lithium/sodium storage.

Synthesis, characterization and photocatalytic performance of novel visible-light-induced Ag/BiOI

Abstract: For the first time, a series of Ag/BiOI photocatalysts with different Ag contents have been synthesized by a hydrothermal combinated with photodeposition method. The as-prepared products were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), high-resolution transmission electron micrographs (HRTEM), X-ray photoelectron spectroscopy (XPS), UV–vis diffuse reflectance spectra (DRS), and photoluminescence (PL) emission spectroscopy. The photocatalytic activities of these Ag/BiOI composites under visible-light irradiation (λ > 420 nm) were evaluated by the degradation of acid orange II, methyl orange (MO) and rhodamine B (RB). The results revealed that the Ag/BiOI composites exhibited much higher photocatalytic activities than pure BiOI. The Ag amount in the Ag/BiOI composites played an important role in the corresponding photocatalytic properties and the optimized ratio was obtained at 0.6%. The significant enhancement in the Ag/BiOI photoactivity could be ascribed to both the effect of Ag deposits by acting as electron traps and the surface plasma resonance effect of Ag.

Complex interactions of pillar[5]arene with paraquats and bis(pyridinium) derivatives

Abstract: The complexation behavior of a series of paraquats (G1·2PF6–G5·2PF6) and bis(pyridinium) derivatives (G6·2PF6–G14·2PF6) with pillar[5]arene (P5A) host has been comprehensively investigated by 1H NMR, ESI mass and UV-vis absorption spectroscopy. It is found that P5A forms 2 : 1 external complexes with N,N′-dialkyl-4,4′-bipyridiniums (G1–G4·2PF6); while it forms 1 : 1 pseudorotaxane-type inclusion complexes with methylene [–(CH2)n–] linked bis(pyridinium) derivatives possessing appropriate chain lengths (n = 3–6, G7–G10·2PF6). Host–guest association constants in dimethyl sulfoxide (DMSO) were determined, indicating G7–G10·2PF6 axles form stable [2]pseudorotaxanes with P5A wheel in this very high polarity solvent and 1,4-bis(pyridinium)butane (G8·2PF6) was the most suitable axle unit. Meanwhile, the nature of the substituents attached to 1,4-bis(pyridinium)butane dramatically affects the molecular recognition behavior. The introduction of pyridyls (G13·2PF6) increases not only the Ka value (4.5 × 102→7.4 × 102 M−1), but also the charge transfer (CT) absorption (colorless→yellow). Furthermore, the solvent effects have also been investigated, showing they significantly influence the association strength during the course of host–guest complexation. Particularly, the Ka value of P5A–G13·2PF6 in 1 : 1 (v:v) acetone-d6/DMSO-d6 is enhanced by a factor of 7.3 compared with pure DMSO-d6 (7.4 × 102→5.4 × 103 M−1).

Synthesis of CeO2 nanorods via ultrasonication assisted by polyethylene glycol.

Abstract: Polycrystalline CeO2 nanorods 5−10 nm in diameter and 50−150 nm in length were synthesized via ultrasonication using polyethylene glycol (PEG) as a structure-directing agent at room temperature The properties of the CeO2 nanorods were characterized by TEM, EDS, XRD, XPS, FT-IR, TG, BET, and UV−vis spectroscopy Various reaction parameters, such as the content of PEG, the molecular weight of PEG, the concentration of KOH, the pH value, and the sonication time, were investigated by a series of control experiments The content of PEG, the molecular weight of PEG, and the sonication time were confirmed to be the crucial factors determining the formation of one-dimensional CeO2 nanorods A possible ultrasonic formation mechanism has been suggested to explain the formation of CeO2 nanorods