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The impact of the anodic second phase, Mg41Nd5in as-extruded Mg–4Li-3Nd-0.2Zn alloy was first reported as a candidate anode material for primary Mg-air batteries. Solid solution treatment of Mg–4Li-3Nd-0.2Zn was conducted at 400, 450, and 500 °C for 8 h. The electrochemical behaviour and discharge performance were investigated using microstructural characterization, electrochemical measurements, and discharge tests. The results indicated that solid solution treatment led to increased grain size and reduced volume fraction of the anodic second phase (Mg41Nd5) with a uniform distribution. In turn, the anode electrochemical activity was promoted, and the bulk effect was reduced. The anode efficiency and comparison capacity were significantly improved. At 5 mA cm−2, the average discharge voltage reached as high as 1.45 V with a utilization efficiency of 61.29%, and a discharge capacity of 1358.98 mAh·g−1for the solid solution-treated sample at 450 °C, making it the excellent candidate anode material for Mg-air batteries.

Surgical failures, caused by postoperative infections of bone implants, are commonly met, which cannot be treated precisely with intravenous antibiotics. Photothermal therapy (PTT) and photodynamic therapy (PDT) have attracted widespread attention due to their non-invasive antibacterial effects on tissues and no bacterial resistance, which may be an excellent approach to solve infections related to bone implants for biodegradable magnesium alloys. Herein, a sodium copper chlorophyllin (SCC) with a porphyrin ring induced Ca–P coating was prepared on AZ31 magnesium alloy via layer-by-layer (LbL) assembly. The morphology and composition of the samples were characterized through field emission scanning electron microscope (FE-SEM) with affiliated energy dispersive spectrometer (EDS), X-ray diffractometer (XRD), and Fourier infrared spectrometer (FTIR) and X-ray photoelectron spectrometer (XPS) as well. Potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and hydrogen evolution experiments were employed to evaluate the corrosion behavior of the samples. Atomic absorption spectrophotometer was used to measure Cu elemental content of different immersion periods. Cytocompatibility and antibacterial performance of the coatings were probed using in vitrocytotoxicity tests (MTT assay), live/dead cell staining and plate counting method. The results showed that the obtained (Ca–P/SCC)10coating exhibited good corrosion resistance, antimicrobial activity (especially under 808 nm irradiation) and biocompatibility. The antibacterial rates for E. coliand S. aureuswere 99.9% and 99.8%, respectively; and the photothermal conversion efficiency was as high as 42.1%. Triple antibacterial mechanisms including photodynamic, photothermal reactions and copper-ions release were proposed. This coating exhibited a promising application for biodegradable magnesium alloys.

Mn-based cathode material Li1.20Mn0.52Ni0.20Co0.08O2was proposed and ameliorated by surface-coating poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) and doping Ga3+. X-ray diffraction and high-resolution transmission electron microscopy studies revealed that part of Ga3+replacing the Ni site could reduce the Li+/Ni2+mixing by forming a well-ordered layered structure and a homogeneous coating layer of PEDOT:PSS is covered on the surface of Li1.20Mn0.52Ni0.19Co0.08Ga0.01O2. The results of the electrochemical studies demonstrated the higher initial charging–discharging Coulombic efficiency, and outstanding rate capabilities and cyclic performance were obtained for the PEDOT:PSS-covered and Ga3+-doped samples. Especially, 2 wt % PEDOT:PSS-coated Li1.20Mn0.52Ni0.19Co0.08Ga0.01O2delivered 38.3 mAh g–1, which is larger than the pristine cathode at a 5C high rate. Meanwhile, it could retain 189.6 mAh g–1(90.3% of its initial discharge capacity at 45 °C) after 300 cycles with a 1C rate, while the pristine cathode only delivered 149.7 mAh g–1with 80.7% cycling retention left. The results strongly suggested that such PEDOT:PSS-coated and Ga3+-doped Mn-based layered structure materials demonstrated high potential as a cathode candidate especially for high-energy applications.

Biomophic titanium oxide with nanocrystalline was successfully synthesized using napkin template, which everybody uses. Unique biomorphic microstructures were characterized by field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM) and nitrogen absorption-desorption techniques. TiO2 material was characterized by repetitious networks consisting of the fibers with diameter of 1-6μm. The results showed that the products were composed by polycrystalline TiO2 nanoparticles with diameter of ca. 5-8 nm and the high specific surface area (81.0 m2·g-1) of sample,which were believed to result from the X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM) and the Brunauer-Emmett-Teller (BET) method. While the concentration of acid black solution was 20 mg/L, catalyst amount 0.1 g/L, the reaction had a higher photocatalytic performance following irradiation with a visible light by xenon lamp, the decoloring rate can reach over 100% after 250 min.

Negative-charged PS microspheres were prepared through emulsifier-free emulsion polymerization method. High-quality PS colloidal crystals were obtained via the horizontal deposition method. Hierarchically ordered macroporous CeO2 sheets were fabricated on fluorine-doped tin oxide (FTO) substrates using PS colloidal crystals as template by a continuous infiltration process. The structure and morphology of the products were characterized by X-ray diffractometer (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM) and nitrogen adsorption-desorption. The characterized results showed that macroporous CeO2 sheets replicated well three-dimensionally (3D) ordered structure derived from PS colloidal crystals template and possessed a relatively large specific surface area. Moreover, the synthesized hierarchical CeO2 sheets showed the highest photocatalytic activity under solar irradiation and also exhibited remarkable ability to remove methylene blue, suggesting they are promising catalyst for wastewater treatment.

Hierarchical porous TiO2 fibre was successfully synthesized using cotton as template. Microstructures of product were characterized by Field Emission Scanning Electron Microscope (FESEM), nitrogen absorption-desorption technique and transmission electron microscopy (TEM). Titanium oxide material was characterized by repetitious networks consisting of the fibres with diameter of ca. 3-8 μm. The results showed that the products were composed 2-5 nm piled pores stacked by polycrystalline TiO2 nanoparticles. The small crystallite diameter (6-10 nm) and the high specific surface area (83.7 m2·g-1) of sample was believed to be resulted from wide-angle X-ray Diffraction (XRD), high resolution TEM (HRTEM) and the BET method. While the concentration of methylthionine chloride solution was 20 mg/L, catalyst amount 0.1 g/L, the reaction had a higher decoloring rate following irradiation with a UV light source, the decoloring rate can reach over 100% after 250 min.

The bionic structure nanoporous TiO2 materials were prepared using aquatic plants as biological templates. The X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), nitrogen adsorption method and ultraviolet-visible light spectrometer were employed to characterize the structure of samples and the degradation performance of methylene blue solution under the visible light. The results showed that TiO2 sample inherited the porous structure of original template. Such bionic material was composed of ultra-thin piece layers which were full of TiO2 nanoparticles with size of about 10 nm. The product was studded with piled pores which had a few to dozens of nanoaperture. The material was doped with a small number of bionic legacy elements which can enhance the absorption of 400-800 nm range of the visible light, thus the bionic nanoporous TiO2 materials had better photocatalytic degradation effects of methylene blue solution in the sun.