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Utilizing natural and renewable natural polysaccharides as substrates to fabricate films or spinning with high metal ion adsorption and retain their mechanical properties is essential but challenging for the treatment of polluted water systems. In this study, the adsorption film was prepared with excellent mechanical properties and adsorption properties by blending chitosan (CS), poly (vinyl pyrrolidone) (PVP), β-cyclodextrin (β-CD), and nanocellulose (NCC). Fourier transform infrared spectroscopy, X-ray diffraction analysis, and scanning electron microscopy were used to investigate the microstructure of the film. The effects of the NCC content, contact time, temperature, initial concentration, and pH on the adsorption of Cu(II) ion were investigated. X-ray photoelectron spectroscopy (XPS) was used to explore the adsorption mechanism. The results showed that a suitable content of NCC enhanced the tensile strength of the CS/PVP/β-CD/NCC composite film and improved its adsorption capacity under acidic conditions. The adsorption kinetics followed the pseudo-second-order kinetic model and the equilibrium data could be better described by the Langmuir isotherm. The thermodynamic parameters indicated that the adsorption of the Cu(II) ion onto the CS/PVP/β-CD/NCC film exhibited physical adsorption and spontaneous process. XPS analysis showed that the nitrogen-containing functional groups play an important role during the adsorption process. Therefore, applying this adsorbent to remove metal ions during wastewater treatment is promising. [ABSTRACT FROM AUTHOR]

Biomimetic surfaces with the hierarchical structure consisting of multilayered pore microstructures and TiO 2 hollow nanostructures were fabricated by combining a modified breath figure method and a dip-coating technique. For creating the hierarchical structure, acetylacetone-chelated and non-chelated tetrabutyltitanates in the coating solution were used as the titanium sources to produce the titanium-based gel film and hollowly nanostructured TiO 2 , respectively. Meanwhile, the smaller and larger water droplets condensed in sequence during the breath figure process were used as the templates to generate the hollow structures and pore structures, respectively. The parameters of the hierarchical structures, including the pore diameter, pore density and the output of TiO 2 hollow nanostructures, were conveniently tailored by varying the volume ratio of tetrabutyltitanate to acetylacetone in the coating solution. The as-prepared titanium-based gel films on glass substrates can be transformed into the corresponding anatase TiO 2 films by a subsequent annealing process. The synthesized films were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction pattern, thermogravimetry and Fourier transform infrared spectroscopy. The designed hierarchical structure effectively endows the films with the rose-like superhydrophobic behavior, and the introduction of TiO 2 hollow nanostructures within multilayered pores plays an important role in the superhydrophobic property and the strong adhesion to a water droplet. • Introduction of chemical reaction in breath figure method. • Two-step condensation of water droplets. • Combination of pore microstructure and hollow nanostructure. • Tailorable parameters of the hierarchical structures. [ABSTRACT FROM AUTHOR]

The solution combustion method was used to prepare single phase hydroxyapatite (HA), β-tricalcium phosphate (β-TCP) and biphasic calcium phosphates (BCP). The powder samples were synthesized with a Ca/P molar ratio from 1.45 to 1.67, and annealed at different temperatures. These samples have been characterized by XRD and FTIR. The amount and lattice parameters of each phase in these samples were refined by the MAUD program. The results of Rietveld refinement show that a single phase HA is obtained with Ca/P ratio of 1.67 and annealing at 1150°C for 3h, β-TCP is isolated with a Ca/P ratio of 1.5 after annealing at 950°C and remains stable up to 1050°C. Apart from above two extremes a whole range of BCP can be prepared with a favorable control of Ca/P ratios and annealing temperatures. [ABSTRACT FROM AUTHOR]