Lamei Wu

Modification of carbon nanotubes could improve and enhance their properties. Four conjugated polymer (CPs)/organic molecules functionalized carbon nanotubes were prepared based on amino-functionalized multi-walled carbon nanotubes (NH2-MWCNT) in this work. Two of them were prepared by Schiff base formation reaction, and another two were prepared by Suzuki coupling reaction. With this procedure, fabrication of CPs/MWCNT composite electronic materials could be achieved. The modified carbon nanotubes were characterized by X-ray photoelectron spectroscopy, thermogravimetric analysis, FTIR, and SEM. The electrochemical properties of these novel carbon nanotubes were studied by Cyclic Voltammetry and galvanostatic charge and discharge measurement. The specific capacitance (0.042F/g) of the MWCNT increases with the increasing amount of CPs grafted onto the MWCNTs (0.283F/g). It is found that the amount of conjugated polymers on the surfaces of MWCNTs could be tuned by adjusting the precursors for the CPs. Accordingly; the specific capacitance of the as-prepared composite materials could be tuned.

Doping multiple halide anions into bismuth terephthalate can effectively improve photocatalytic activities. The F^–, Cl^–, Br^– codoped hybrids exhibit excellent photocatalytic activities on RhB and salicylic acid.

A serials of biomimetic photocatalyst zinc(II) meso-tetra(4-carboxyphenyl)porphyrinato (ZnTCP)-sensitized 3D hierarchical TiO2 hollow nanoboxes (TiO2-HNBs) assembled by six ordered nanosheets with dominant {001} facets exposure (ZnTCP@TiO2-HNBs) have been successfully synthesized by a facile one-pot solvothermal method via a topological transformation process with TiOF2 as template. Infrared spectra (IR), UV-vis spectroscopy, and X-ray photoelectron spectroscopy (XPS) confirmed that ZnTCP played a decisive role in constructing 3D hollow nanoboxes through the formation of ester bond combined to TiO2-HNBs, which also provided a transferring photo excited electrons bridge to sensitize TiO2-HNBs for enhancing visible-light response. Due to the superior sensitization and biomimetic activity of ZnTCP, the photodegradation rate of rhodamine B (RhB) of as-prepared ZnTCP@TiO2-HNBs with ZnTCP/TiOF2 mass ratio of 2% (T-2p) improves 3.6 times compared to that of TiO2-HNBs with a degradation yield of 99% for 2 h under simulated sunlight irradiation (> 420 nm). The enhanced photodegradation ability was attributed to synergistic visible photocatalytic mechanism of biomimetic catalyst, which can not only produce hydroxyl radical (•OH) and superoxide radical (•O2−) coming from the excitation process of ZnTCP sensitized TiO2-HNBs, but also generate singlet oxygen (1O2) that was only provided by biomimetic enzyme porphyrins. Furthermore, the photocatalyst showed good recycling stability and dispersibility after five rounds, ascribed to ZnTCP strong chemical bonding to the support TiO2-HNBs. By means of electrochemical cyclic voltammetry analysis, the effect of central zinc ions and parent porphyrin rings on the redox property of biomimetic catalyst was studied.

N-Methyl-N′-2-hydroxybenzaldehyde acylhydrazones have been chemospecifically synthesized in good yield by N-methylation of the Fe(III) complexes of N-2-hydroxybenzaldehyde acylhydrazones with methyl iodide in tetrahydrofuran. The reaction proceeds with the exclusive formation of the N-methyl derivative without any concurrent O-methylation side reactions. In addition, the N-methylation reaction occurred simultaneously with a complete deprotection step (elimination of the metal ion). As a result, the N-methyl product was obtained in excellent purity without time-consuming chromatographic workup. A free N-2-hydroxybenzaldehyde acylhydrazone ligand could not be methylated under the same conditions.