SnO2 with a nano-rod morphology shows a superior catalytic performance over SnO2 with other morphologies for CO oxidation. The SnO2-rods’ catalytic behavior is very similar to that of a noble metal catalyst.

A new method was reported for preparing a magnetically responsive superhydrophobic surface by electrostatic air spray deposition (EASD) and magnetic induction. The mixture was fully atomized under the combined action of the electrostatic field and the high-speed airflow field, and a dense array of micropillars was formed. The atomization mechanism of EASD was explored. The distribution and physical parameters of the micropillars were evaluated and counted. Switchable adhesion characteristics of the surface and the reversibility in 10 cycles were examined. The influences of different electrostatic voltages, component concentration, spray distance, air pressure, and magnetic field intensity on the surface morphology and hydrophobicity were analyzed. The prepared surface can be reversibly transformed between the high-adhesion state (with a contact angle of 108°) and the low-adhesion state (with a contact angle of 154°) by on/off switching of an external magnetic field. After a 2.2 kPa pressure load was applied, the surface contact angle was 144° with an applied magnetic field of 0.4 T. After heated at 90 °C for more than 90 min, the surface can almost obtain superhydrophobicity (with a contact angle of 148°) in the absence of a magnetic field. By utilizing the switchable surface adhesion characteristics, various kinds of droplet transmissions were realized. When the cured surface was spray-coated with carbon nanoparticles (CNPs), active droplet manipulation can be achieved by simply moving the magnet. The advantages of this method include a simple preparation process without chemical surface modification.

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A zeolite/polyimide composite separator with a spongy-like structure was prepared by phase inversion methods based on heat-resistant polyimide (PI) polymer matrix and ZSM-5 zeolite filler, with the aim to improve the thermal stability and electrochemical properties of corresponding batteries. The separator exhibits enhanced thermal stability and no shrinkage up to 180 °C. The introduction of a certain number of ZSM-5 zeolites endows the composite separator with enhanced wettability and electrolyte uptake, better facilitating the free transport of lithium-ion. Furthermore, the composite separator shows a high ionic conductivity of 1.04 mS cm−1 at 25 °C, and a high decomposition potential of 4.7 V. Compared with the PP separator and pristine PI separator, the ZSM-5/PI composite separator based LiFePO4/Li cells have better rate capability (133 mAh g−1 at 2 C) and cycle performance (145 mAh g-1 at 0.5 C after 50 cycles). These results demonstrate that the ZSM-5/PI composite separator is promising for high-performance and high-safety lithium-ion batteries.

The poor cycle stability and reversibility seriously hinder the widespread application of SnO2 materials as anodes for lithium-ion batteries (LIBs). A novel sandwich-architecture composite of Si-doped SnO2 nanorods and reduced graphene oxide with carbon sealing (Si-SnO2@G@C) is engineered and fabricated by a facile two-step hydrothermal process and subsequent annealing treatment, which exhibit not only extraordinary rate performance and ultrahigh reversible capacity but also excellent cycle stability and high electrical conductivity as the anode of LIBs. The Si-doped SnO2 nanoparticles on the surface of graphene were firmly wrapped in the C-coating and formed a porous sandwich structure, which can efficiently prevent the Sn nanoparticles from aggregation and provide more extra space for accommodating the volume variations and more active sites for reactions. The carbon layer also blocks the direct contact of the SnO2 nanorods with electrolyte and prevents the graphene nanosheets from the restacking. More importantly, the reversibility of lithiation/delithiation reactions can be remarkably improved by the doping silicon. The doped Si not only accelerates the diffusion of Li+ but also brings a significant increase in the specific capacity. As a consequence, the Si-SnO2@G@C nanocomposite can maintain a high capacity of 654 mAh/g at 2 A/g even after 1200 cycles with negligible capacity loss and excellent reversibility with a Coulombic efficiency retention over 99%, which can be capable of the alternative to commercial graphite anodes. This work provides a new strategy for the reasonable design of advanced anode materials with superior and reversible lithium storage capacity.