Preparation of Boron-Doped Porous Titania Networks Containing Gold Nanoparticles with Enhanced Visible-Light Photocatalytic Activity

The ability to decrease the electron/hole recombination rate, and decrease the band gap of titania to allow photoactivity on irradiation with visible light is attracting more and more attention. Here, boron doping of the titania, the deposition of gold nanoparticles, along with a meso-macroporous structure were obtained using a facile agarose gel templating process combined with sol–gel chemistry. The Au/B/TiO₂ nanocomposites were characterized using SEM, TEM, XRD, N₂ gas sorption, diffuse UV–vis, photoluminescence, and SIMS. The photocatalytic activity was assessed by degradation of an organic probe molecule (methylene blue) under visible light (λ > 420 nm). The resulting materials achieved photocatalytic activities up to 50% greater than the commercial Degussa P25 under visible light. The enhancement in photocatalytic activity was primarily attributed to the decrease in band gap as a result of the boron doping and its influence on the anatase to rutile phase formation: The doped materials were highly crystalline and an optimum anatase to rutile ratio (3:1) was obtained with 0.25 wt % boron in the sample calcined at 650 °C. In addition, the presence of the gold nanoparticles decreased recombination between the photoexcited electrons and holes, which further improved the photocatalytic activity

Blue Thermally Activated Delayed Fluorescence Polymers with Nonconjugated Backbone and Through-Space Charge Transfer Effect

We demonstrate novel molecular design for thermally activated delayed fluorescence (TADF) polymers based on a nonconjugated polyethylene backbone with through-space charge transfer effect between pendant electron donor (D) and acceptor (A) units. Different from conventional conjugated D–A polymers with through-bond charge transfer effect, the nonconjugated architecture avoids direct conjugation between D and A units, enabling blue emission. Meanwhile, spatial π–π interaction between the physically separated D and A units results in both small singlet–triplet energy splitting (0.019 eV) and high photoluminescence quantum yield (up to 60% in film state). The resulting polymer with 5 mol % acceptor unit gives efficient blue electroluminescence with Commission Internationale de l’Eclairage coordinates of (0.176, 0.269), together with a high external quantum efficiency of 12.1% and low efficiency roll-off of 4.9% (at 1000 cd m^–2), which represents the first example of blue TADF nonconjugated polymer

Probing the Effects of Templating on the UV and Visible Light Photocatalytic Activity of Porous Nitrogen-Modified Titania Monoliths for Dye Removal

Porous nitrogen-modified titania (N-titania) monoliths with tailored morphologies were prepared using phase separation and agarose gel templating techniques. The doping and templating process were simultaneously carried out in a one-pot step using alcohol amine-assisted sol–gel chemistry. The amount of polymer used in the monoliths that were prepared using phase separation was shown to affect both the physical and optical properties: higher poly­(ethylene glycol) content increased the specific surface area, porosity, and visible light absorption of the final materials. For the agarose-templated monoliths, the infiltration conditions affected the monolith morphology. A porous monolith with high surface area and the least shrinkage was obtained when the N containing alkoxide precursor was infiltrated into the agarose scaffolds at 60 °C. The effect of the diverse porous morphologies on the photocatalytic activity of N-titania was studied for the decomposition of methylene blue (MB) under visible and UV light irradiation. The highest visible light activity was achieved by the agarose-templated N-titania monolith, in part due to higher N incorporation. This sample also showed better UV activity, partly because of the higher specific surface area (up to 112 m² g^–1) compared to the phase separation-induced monoliths (up to 103 m² g^–1). Overall, agarose-templated, porous N-titania monoliths provided better features for effectively removing the MB contaminant

The funnel plot of OS on patients with newly diagnosed GB.

<p>The funnel plot of OS on patients with newly diagnosed GB.</p

The PRISMA flow chart of the meta-analysis.

<p>The PRISMA flow chart of the meta-analysis.</p

The pooled HR of median OS comparing BV with ST in patients with GB.

<p>The pooled HR of median OS comparing BV with ST in patients with GB.</p

The pooled HR of median PFS comparing BV with ST in patients with GB.

<p>The pooled HR of median PFS comparing BV with ST in patients with GB.</p

Characteristics of included studies.

<p>Characteristics of included studies.</p

The incidence of all severe AEs in patients with newly diagnosed GB.

<p>The incidence of all severe AEs in patients with newly diagnosed GB.</p

The pooled analysis of OS rate comparing BV with ST in patients with GB at different follow-ups.

<p>The pooled analysis of OS rate comparing BV with ST in patients with GB at different follow-ups.</p