Shasha Gao

Sandwich-Like CNT@Fe3O4@C Coaxial Nanocables with Enhanced Lithium-Storage Capability

Through the combined method of a low-temperature reflux and calcination, porous sandwich-like CNT@Fe3O4@C coaxial nanocables were cleverly constructed, which exhibited a favorable specific capacity of 724.8 mA h g-1 at 1000 mA g-1, a satisfying rate performance and admirable Coulombic efficiency (ca. 100%) for anodes of lithium-ion batteries. Due to the enlarged contact surface area, shortened Li+ diffusion distance, hierarchical porosity, reasonable structural design and good structural stability, the electrochemical performance of the CNT@Fe3O4@C nanocomposites was greatly enhanced in comparison with the traditional iron oxide anodes. So, it is a good candidate for anode materials with high performance.

Rational design of hybrid porous nanotubes with robust structure of ultrafine Li4Ti5O12 nanoparticles embedded in bamboo-like CNTs for superior lithium ion storage

Robust hybrid porous bamboo-like carbon nanotubes (CNTs), with ultrafine Li4Ti5O12 nanoparticles homogeneously embedded, are synthesized by a facile sol–gel process, combined with subsequent heat treatment. The nanohybrids exhibit a reversible capacity as high as 582.4 mA h g−1 at 0.2 A g−1 after 500 cycles, together with excellent rate capability and long-term cycling stability at high current densities. A high discharge capacity of 114.2 mA h g−1 at 5 A g−1 is attained for up to 3000 cycles. The superior electrochemical performance of the nanohybrids is attributed to their structure rather than their composition. Their exceptional electrochemical performance benefits from the high electrical conductivity of the porous carbon matrix, which not only provides continuous three-dimensional electron transportation routes but also simultaneously solves the major problems of pulverization, loss of electrical contact, and particle aggregation of Li4Ti5O12 anode. In addition, the highly dispersive, ultrafine Li4Ti5O12 nanoparticles greatly shorten the diffusion paths for both electrons and ions. Such a structure not only preserves all the advantages of one-dimensional nanostructures, but also offers potential for a high packing density of electrode materials. Surely, this strategy can be widely extended to other anode materials.

One-dimensional controllable crosslinked polymers grafted with N-methyl-D-glucamine for effective boron adsorption

In this research, a series of one-dimensional controllable crosslinked polymers with the different mass ratios of 4-vinylbenzychloride (VBC) and divinyl benzene (DVB) was prepared via cationic polymerization, and the polymers were grafted with the functional group N-methyl-D-glucamine (NMDG) for boron removal. The optimum polymeric mass ratio and a series of boron adsorption performances were studied. The maximum adsorption capacity was 18.15 mg g−1, of which 94% was retained after 4 cycles. Meanwhile, different pH values had negligible effect on the boron adsorption capacity, which was favorable for the removal of boron from its aqueous solution in a wide pH window. In addition, a magnetic adsorbent was prepared by the combination of Fe3O4 nanoparticles and the polymer, which provided an effective way to collect and recover adsorbents from their aqueous solutions.

Pseudocapacitive Behaviors of Li2FeTiO4/C Hybrid Porous Nanotubes for Novel Lithium-Ion Battery Anodes with Superior Performances

Hybrid nanotubes of cation disordered rock salt structured Li2FeTiO4 nanoparticles embedded in porous CNTs were developed. Such unique hybrids with continuous 3D electron transportation paths and isolated small particles have been shown to be an ideal architecture that brought out enhanced electrochemical performances. Meanwhile, they exhibited improved extrinsic capacitive characteristics. In addition, we demonstrate a successful example to use cathode active material as anode for lithium-ion batteries (LIBs). More importantly, our hybrids had much superior electrochemical performances than most of the reported Li4Ti5O12-based nanocomposites. Therefore, it is concluded that Li2FeTiO4 can be a prospective anode material for LIBs.

Solid-state photochromic behavior of pyrazolone 4-phenylthiosemicarbazones

Solid-state photochromic materials have attracted much more attention due to their actual potential applications in photoactive devices. Here, three new compounds (1-phenyl-3-methyl-4-(3-fluoro/chloro/bromobenzal)-5-hydroxypyrazole 4-phenylthiosemicarbazones) were synthesized, which exhibited reversible solid state photochromic properties upon UV/Vis light irradiation. Their photochromic properties, first-order kinetics and fatigue resistance were investigated by time-dependent UV-Vis absorption spectroscopy. The results showed that their fatigue resistance and addressability were enhanced with the increase in the electron-withdrawing ability of the substituents on the phenyl group at the 4-position of the pyrazolone ring. Thus, 1-phenyl-3-methyl-4-(3-fluorobenzal)-5-hydroxypyrazole 4-phenylthiosemicarbazone exhibited good photochromic properties and high fatigue resistance. Based on single crystal X-ray diffraction and FT-IR analyses, the photochromic mechanism involved intra/intermolecular proton transfer.