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Hierarchically porous carbons are of increasing importance due to their special physicochemical properties. The state-of-the-art approaches for synthesizing hierarchical porous carbon with network structure normally suffer from specific chemistries, rigid reaction conditions, high cost, and multiple tedious steps that limit their large scale production. Herein, we present an interesting insight into the important role of Teflon additive in fabrication of hierarchical porous carbon derived from biomass and, thus, use natural Indicalamus leaves for the first time to successfully synthesize hierarchical porous carbon with a three-dimensional morphology of interconnected nanoparticle units by using a facile and post-treatment-free carbonization technique. It is surprisingly found that the addition of Teflon not only reduces the synthesis procedure by combining post-removal of silica and carbonization in a single step but also plays a decisive role in generating the hierarchical carbonaceous network structure with a specific surface area as high as 1609 m 2 /g without any extra activation procedures. Benefiting from the combination of well-developed porosity and valuable hierarchical porous morphology, this type of hierarchical porous carbon has demonstrated attractive liquid-phase adsorption properties toward organic molecules.

Tm doped TiO 2 nanoparticles have been synthesised by hydrolysis-precipitation method. The effect of heat treatment on the crystal phase and photocatalytic activity of Tm doped TiO 2 nanoparticles has been studied. The prepared samples were characterised by transmission electron microscopy, X-ray diffraction, Fourier transformed infrared and diffuse reflection spectrum analysis. The results show that Tm 3z doping can effectively inhibit the phase transformation from antase to rutile and decrease the crystallite size of nano-TiO 2 particles. There is an optimal Tm doping (1?4 mol.-%) after calcination at 550uC for the photocatalytic activity of methylene blue degradation.

Gd 3z doped TiO 2 nanopowders were successfully synthesised by sol-gel method using gadolinium nitrate and tetra-n-butyl titanate as the precursors. The as prepared nanopowders were characterised by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results indicated that Gd 3z doping effectively inhibits the phase transformation from anatase to rutile until 700uC, which was propitious to promote the catalytic activity of the catalysts. The fine and uniform Gd 3z doped TiO 2 nanopowders with the size of 10-15 nm were obtained using the 0 . 75 g L 21 hydroxypropyl cellulose (HPC) as dispersant for the excellent steric stabilisation. Compared with the nanocrystalline TiO 2 , the Gd 3z doped TiO 2 nanopowders exhibited higher photocatalytic activity to methylene blue degradation.

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