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In this report, Ni and TiO 2 are successfully embedded into porous carbon aerogel (CA) (donated as Ni TiO 2 @CA). Meanwhile, the synergistic effect of Ni, TiO 2 and CA on the dehydrogenation properties of LiBH 4 is systematically studied. Ni@CA, TiO 2 @CA and CA are also investigated for comparisons. Compared to other three materials, Ni TiO 2 @CA exhibits better performance when used as a carrier to support LiBH 4 . More than 6.75 wt% H 2 is released from LiBH 4 Ni TiO 2 @CA system in nearly 120 min at 350 °C, exhibiting a higher dehydrogenation capacity than that of LiBH 4 Ni@CA (3.15 wt %), LiBH 4 TiO 2 @CA (5.15 wt%) and LiBH 4 -CA (2.05 wt %), respectively. Furthermore, the apparent energy (Ea) calculated with Kissinger method is 118.8 kJ/mol, much lower than that of pure LiBH 4 . Dehydrogenation performance of LiBH 4 Ni TiO 2 @CA may be due to the synergetic effect of destabilization of TiO 2 , catalysis of Ni, as well as the nanoconfinement of CA. [ABSTRACT FROM AUTHOR]

SiNPs@AgNPs were well designed and utilized as the probes for hydrogen peroxide detection based on the "off–on" fluorescence sensing and "on–off" color sensing platforms. [Display omitted] • SiNPs were synthesized by a one-step, simple, and green method. • SiNPs@AgNPs was constructed as the probe for H 2 O 2 detection with fluorescent and colorimetric spectra. • The fabricated sensor exhibited wide linear ranges and low limit of detections for H 2 O 2. • The sensor showed the ability for accurate determination of H 2 O 2 in complex samples. Fluorescent silicon nanoparticles (SiNPs) were synthesized by a one-step, simple, and green method with 3-Aminopropyltriethoxysilane (APTES) and ascorbic acid (AA) as reaction agents. Subsequently, the SiNPs and AgNPs nanocomplex (SiNPs@AgNPs) was constructed as the probe for hydrogen peroxide (H 2 O 2) detection. The fluorescence of SiNPs was quenched due to the surface plasmonic-enhanced energy transfer between SiNPs and AgNPs. Meanwhile, the color tends to be yellow due to the existence of AgNPs. As the AgNPs were etched by H 2 O 2 , the fluorescence recovers and color fadings. Based on the well-designed structure, the "off–on" fluorescence sensing and "on–off" color sensing platforms for H 2 O 2 were fabricated. The as-synthesized materials were characterized by Fourier transform infrared (FT-IR) spectroscopy, dynamic light scattering (DLS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Fluorescence and UV–vis absorption spectra were used to evaluate the optical performance. The fabricated sensor exhibited a linear range of 1.0–100.0 μM, with a limit of detection of 0.36 μM for the fluorescence sensing of H 2 O 2. Additionally, a linear range of 1.0–50.0 μM and a limit of detection of 0.45 μM were displayed for the detection of H 2 O 2 by colorimetric assay. The feasibility in complex medium of the fabricated fluorescent and colorimetric dual-signal sensor was evaluated by the detection of H 2 O 2 in phosphate buffer saline (PBS) and lake water samples. [ABSTRACT FROM AUTHOR]

A synergistic effect of nanoconfinement and catalyzing is a new strategy to enhance the dehydrogenation properties of complex hydrides. Herein, LiBH4 has been infiltrated into a CoNiB-loaded carbon aerogels system (donated as LiBH4@CA@CoNiB). It is found that the desorption performances of LiBH4 are significantly strengthened. The onset desorption temperature of LiBH4@CA@CoNiB is decreased to 192 °C, and majority of the liberation occurs at about 320 °C, much lower than that of pure LiBH4. Also, about 15.9 wt% H2 could be released below 600 °C. Furthermore, LiBH4 doped with CA@CoNiB exhibits an excellent desorption kinetics, with a capacity of 9.33 wt% H2 released in 30 min at 350 °C, while only 2.13 wt% H2 is gained for bulk LiBH4. In addition, the apparent activation energy (Ea) is reduced sharply from 59.00 kJ/mol (pure LiBH4) to 46.39 kJ/mol. [ABSTRACT FROM AUTHOR]

Abstract: Porous Sn-doped TiO2 monoliths were fabricated with polystyrene spheres as a template using a sol–gel method, and followed by calcination at high temperature. Sn doping can suppress the electron/hole recombination through facilitating charge rectification. And its porous structure can provide large surface areas, leading to more adsorption and fast transfer of pollutants. The Sn-doped TiO2 monoliths were characterized by XRD, SEM and BET measurements. In order to evaluate the photocatalytic activity of porous Sn-doped TiO2 monoliths, the photodegradation for methyl orange was performed under UV–vis irradiation. At the same conditions, porous Sn-doped TiO2 monoliths showed the better behavior of photodecomposition for organic compounds than Degussa P25. [Copyright &y& Elsevier]