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Abstract: Stable, neutral TiO2 hydrosols were prepared using TiCl4 as titanium source, HNO3 as peptizing agent, and SiO2 as stabilizer. Based on XRD, TEM, and FTIR measurements, the TiO2 was rodlike anatase crystallite with a major axis of 15–25 nm and a minor axis of 5 nm. Tih name="sbnd" />Si bonds were formed, which suppressed the TiO2 grain growth and stabilized the TiO2 hydrosols. The isoelectric points (IEP) of the series hydrosols were 3.1–4.7 pH values and the absolute zeta potentials of the SiO2-modified TiO2 hydrosols were much higher than 50.0 mV under neutral conditions. Methylene blue and reactive brilliant red X-3B were taken as the simulated pollutants to study the adsorption and photocatalytic properties of the obtained hydrosols. The results suggested that the prepared hydrosols had strong adsorption capacity for cationic pollutants rather than anionic ones, and high photodegradation rate of both cationic and anionic pollutants. [Copyright &y& Elsevier]

[Display omitted] • Dielectric BT nanoparticles anchoring on the surface of SNCM by simple wet coating method. • Enhanced Li+ ion transport and stabilized cathode/electrolyte interface structure, thus improving the rate performance. • Inhibited diffusion-induced SOC gradient resulting in high structure stability of single crystal NCM. The single-crystal Ni-rich Li(Ni x Co y Mn 1−x−y)O 2 cathode (NCM) demonstrates better cycle performance, enhanced tap density and improved mechanical structure stability, compared with polycrystalline NCM. However, limited Li+ transports, (0 0 3) plane slips and microcracks in large single particles hinder rate capability and cycle performance. To overcome these shortcomings, single-crystal NCM cathodes have been modified by nanosized tetragonal BaTiO 3. Due to the dielectric properties, BaTiO 3 particles induce electric field concentration at the BaTiO 3 -NCM-electrolyte interface. Thus, a large amount of lithium vacancies can be formed, providing sufficient sites for the hopping diffusion of lithium ions, thereby significantly enhancing the diffusion coefficient of Li+. Moreover, the redistribution of charges can inhibit the formation and accumulation of cathode-electrolyte-interface. Owing to the synergetic effect of BaTiO 3 , the BT-modified single-crystal NCM with the optimized loading shows a remarkable initial discharge capacity of 138.5 mAh g−1 and maintains 53.8% of its initial discharge capacity after 100 cycles under 5C at 4.5 V cut-off voltage. Overall, the proposed dielectric cathode-electrolyte-interface strategy can enhance Li+ ion transport and stabilize the interface structure, leading to improved rate performance. Meanwhile, the diffusion-induced state of charge gradient can also be inhibited, resulting in high structure stability of single-crystal NCMs under high rate and cut-off voltage cycling. [ABSTRACT FROM AUTHOR]

Abstract: Size-controlled ZrO2 nanorods were prepared via a facile hydrothermal treatment approach in the presence of NH4F as mineralizer. The effects of the type and concentration of mineralizers on the particle size and dispersibility of ZrO2 nanorods were investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM), N2 adsorption–desorption measurements (BET), and X-ray photoelectron spectroscopy (XPS), confirming the essential role of F− in tuning the particle size. Humidity sensors based on ZrO2 nanorods with different sizes exhibit different sensitivity depending on their proportion of surface adsorbed oxygen. High sensitivity, linear response, small hysteresis, and rapid response-recovery behavior (5s for adsorption and 38s for desorption) make ZrO2 prepared by our method a good candidate for application in humidity sensor. The complex impedance spectra were used to elucidate its humidity sensing mechanism in detail. [Copyright &y& Elsevier]