MODIFICATION OF MULTI-WALLED CARBON NANOTUBES WITH POLY(NITRILOETHYLENENITRILOVINYLENE)“GRAFTING TO”THE SURFACE

A mild and facile way was used to prepare poly(nitriloethylenenitrilovinylene)-grafted multi-walled carbon nanotubes(MWCNTs-g-PNENV)nanocomposites via the"grafting to"method.The MWCNTs-g-PNENV nanocomposites are well dispersible in polar solvents such as water,tetrahydrofuran and ethanol.Chemical structure of the resulting product was characterized by Fourier transform infrared(FTIR)spectroscopy,transmission electron microscopy(TEM)and thermal gravimetric analysis(TGA).FTIR showed that the"grafting to"process belonged to covalent attachment mechanisms.TEM observations indicated that the MWCNTs were coated with a uniform PNENV layer,and the MWCNTs existed as a hard backbone.TGA data also showed that the PNENV shell was successfully grafted to the side wall of MWCNTs.

Prediction of Henry Constants and Adsorption Mechanism of Volatile Organic Compounds on Multi-Walled Carbon Nanotubes by Using Support Vector Regression

Support vector regression （SVR） combined with particle swarm optimization for its parameter optimization is employed to establish a model for predicting the Henry constants of multi-walled carbon nanotubes （MWNTs） for adsorption of volatile organic compounds （VOCs）. The prediction performance of SVR is compared with those of the model of theoretical linear salvation energy relationship （TLSER）. By using leave-one-out cross validation of SVR test Henry constants for adsorption of 35 VOCs on MWNTs, the root mean square error is 0.080, the mean absolute percentage error is only 1.19~, and the correlation coefficient （R2） is as high as 0.997. Compared with the results of the TLSER model, it is shown that the estimated errors by SVR are ali smaller than those achieved by TLSER. It reveals that the generalization ability of SVR is superior to that of the TLSER model Meanwhile, multifactor analysis is adopted for investigation of the influences of each molecular structure descriptor on the Henry constants. According to the TLSER model, the adsorption mechanism of adsorption of carbon nanotubes of VOCs is mainly a result of van der Waals and interactions of hydrogen bonds. These can provide the theoretical support for the application of carbon nanotube adsorption of VOCs and can make up for the lack of experimental data.

Covalent and Non-covalent Chemical Modification of Multi-walled Carbon Nanotubes with Tetra-（4-hydroxylphenyl）porphyrin and Its Complexes

Multi-walled carbon nanotubes （MWNTs） were covalently and non-covalently functionalized with tetra- （4-hydroxylphenyl） porphyrin （THPPH2） and its complexes （ZnTHPP） forming dispersible nanohybrids in organic solution. The morphology of the nanohybrids was observed with transmission electron microscopy. The structure of the product was characterized by FT-IR, UV-Vis spectrophotometer, fluorescence spectroscopy and thermogravim- etric analysis. The photo-induced electron-transfer process of the nanohybrids in organic solution was also revealed.

Radiation induced graft polymerization of multi-walled carbon nanotubes for superhydrophobic composite membrane preparation

Highly soluble multi-walled carbon nanotubes （MWNTs） were prepared by radiation-induced free radical graft polymerization of vinyl acetate （VAc） onto pristine MWNT surfaces. High resolution transmission electron microscopy （HR-TEM）, Fourier transform infrared （FT1R） spectroscopy, and micro-Raman spectroscopy were used to confirm that poly（vinyl acetate） （PVAc） had been successfully grafted onto the surface of the MWNTs. The effects of experimental parameters on the degree of graft- ing （DG） of PVAc were also investigated, including adsorbed dose, dose rate, initial monomer concentration, and solvents. The grafted MWNTs （MWNTs-g-PVAc） exhibited good solubility in common organic solvents at high mass fraction. In addition, a superhydrophobic composite membrane could be readily fabricated by vacuum filtration of MWNTs-g-PVAc onto a support- ing membrane, as was confirmed by water contact angle testing and visualization by scanning electron microscopy.

Multi-walled carbon nanotubes as novel promoter of catalysts for certain hydrogenation and dehydrogenation reactions

From the chemical catalysis viewpoint,the excellent performance of CNTs in adsorption-activation of H2 and in promoting spillover of adsorbed H-species is very attractive,in addition to their nanosize channels,sp2-C constructed surfaces,and high thermal/electrical conductivity.This review examines some recent progresses of CNTs as a novel support or promoter of catalysts for certain hydrogenation or dehydrogenation reactions,e.g.,hydrogenation-conversion of syngas to yield alcohols and decomposition or steam-reforming of methanol to generate H2,mainly based on recent work carried out in our laboratory.

Carbon nanotubes as conducting support for potential Mn-oxide electrocatalysts： Influences of pre-treatment procedures

Different oxygen and nitrogen containing functional groups were created on the surface of the multiwalled carbon nanotubes. The multi-walled carbon nanotubes were treated in ultrasonic bath with sulfuric or nitric acid. Furthermore the surface texture was modified by increase of the roughness. In particular after treatment with the oxidizing nitric acid, in comparison to the H2SO4 or ultra-sonic treated samples,craters and edges are dominating the surface structures. Manganese oxide was deposited on the multiwalled carbon nanotubes by precipitation mechanism. Various manganese oxides are formed during the deposition process. The samples were characterized by elemental analysis, microscopy, thermal analysis,Raman spectroscopy, and by the zeta potential as well as X-ray diffraction measurements. It was shown that the deposited manganese oxides are stabilized rather by surface texture of the multi-walled carbon nanotubes than by created functional groups.

多壁碳纳米管载体的改性及应用

多壁碳纳米管独特的结构和性质(纳米尺寸、介孔结构和大比表面积)使其成为催化剂的良好载体。侧重于催化领域的应用,结合改性的多壁碳纳米管为载体的催化剂在各催化反应中的应用,综述了催化领域中多壁碳纳米管载体的改性方法,指出针对不同的催化反应需采用不同的方法或多种方法相结合对碳纳米管进行表面改性修饰。

NH_3等离子体优化MnO_x/MWCNTs催化剂低温选择性催化还原性能

采用介质阻挡放电产生低温NH3等离子体对多壁碳纳米管(MWCNTs)进行表面改性,并在其表面上负载活性组分Mn Ox,用于低温选择性催化还原脱硝。运用SEM、BET、Raman、FT-IR、XPS和NO-TPD对材料进行表征,结果表明,NH3等离子体能够增加MWCNTs载体的表面缺陷程度,并且在其表面上引入吡啶类和吡咯类含氮基团;与载体未经过NH3等离子体改性的催化剂相比,改性的催化剂活性提高,这与载体MWCNTs表面缺陷增多以及含氮基团的引入,进而提高了催化剂对NO的吸附性能有关。