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In this study, Ag and Cu2O nanoparticles modified flower-like ZnO nanostructures have been successfully synthesized by stepwise method, and the photocatalytic properties were investigated in detail. High-resolution transmission electron microscopy, X-ray diffractions analysis, X-ray photoelectron spectroscopy and scanning electron microscopy were used to analyze the samples. Meanwhile, the derived nanoparticles’ structured and morphologic characters were analyzed by Brunauer–Emmett–Teller. The results have shown that the 3D flower-like ZnO microspheres were composed of 2D ZnO nanosheets decorated Ag and Cu2O and exhibiting flower-like Ag@Cu2O/ZnO architectures. We studied the optical absorption (UV–vis) as well as emission (PL) characters of the specimen and the outcomes suggested more superior photocatalytic characteristics for cuprous oxide and silver co-doped zinc oxide sample compared to other samples. Electron Paramagnetic Resonance test results show that there are mainly ⋅ O 2 − , h + and O H • free radicals in the process of CR degradation. A Radical-trapping test indicated that of ⋅ O 2 − and h + was more effective than O H • in the degradation of CR.

A new method to enhance the flexural strength of porous β-tricalcium phosphate (β-TCP) scaffolds was developed. This new method provides better control over the microstructures of the scaffolds and enhances the scaffolds’ mechanical properties. Using this technique, we were able to produce scaffolds with mechanical and structural properties that cannot be attained by either the polymer sponge or slip-casting methods alone or by simply combining the polymer sponge and slip-casting methods. The prepared scaffolds had an open, uniform, interconnected porous structure with a bimodal pore size of 100.0–300.0 μm. The flexural strength of the bimodal porous β-TCP scaffold sintered at 1200 °C was 56.2 MPa and had porosity of 61.4 vol%. The scaffolds obtained provide good mechanical support while maintaining bioactivity, and hence, these bioscaffolds hold promise for applications in hard-tissue engineering.

A bimodal porous hydroxyapatite (HAp) body with high flexural strength was prepared through slip casting. The effect of different particle sizes on the flexural strength and microstructure of three different types of hydroxyapatite (HAp) powders was studied. The powder characteristic of laboratory-synthesized HAp powder (L-HAp) was obtained through a wet-milling method, drying and heating of a mixture of calcium hydrogen phosphate di-hydrate and calcium carbonate. The median particle size of L-HAp was 0.34 μm, and the specific surface area was 38.01 m 2 /g. The commercial HAp had median particle sizes for the K-HAp (Kishida chemical Co. Ltd., K-HAp) and T-HAp (Taihei chemical Co. Ltd., T-HAp) of 1.13 and 3.65 μm, and specific surface areas of 11.62 and 6.23 m 2 /g, respectively. The different powder characteristics affected the slip characteristics, and the flexural strength and microstructure of the sintered porous HAp bodies were also different. The flexural strengths of the porous HAp ceramics prepared by heating at 1200 °C for 3 h in air were 17.59 MPa for L-HAp with a porosity of 60.48%, 3.92 MPa for commercial K-HAp with a porosity of 79.37%, and 4.55 MPa for commercial T-HAp with a porosity of 76.46%.