As a rapid uniform and efficient heating method, microwave irradiation has been widely used in chemical reaction and preparing nanomaterials. Here Pt/carbon nanotube(CNT) catalysts with w(Pt)=18.1% and 9.4 % were rapi...As a rapid uniform and efficient heating method, microwave irradiation has been widely used in chemical reaction and preparing nanomaterials. Here Pt/carbon nanotube(CNT) catalysts with w(Pt)=18.1% and 9.4 % were rapidly synthesized by microwave irradiation heating polyol process and employing the ethylene glycol solution of H 2PtCl 6 as the precursors in the presence of CNT support. TEM imaging showed that microwave-prepared Pt nanoparticles were very uniform in size, with an average size of 3.1 nm, and uniformly dispersed on the CNT surface. Electrochemical experiments demonstrated that microwave-synthesized Pt/CNT catalysts exhibited a higher catalytic activity for electrooxidation of liquid methanol than E-TEK Pt/C. The significant improvement in catalyst performance derives from that microwave-synthesized Pt nanoparticles have a uniform small particle size and uniforml dispersion on the CNT surface.展开更多
Several Ti supported oxide anodic materials are prepared by thermal decomposition method and the anodic kinetic parameters ( a,b,i 0) are determined in 1 mol/L H 2SO 4 solution. The SEM photographs of the electrodes a...Several Ti supported oxide anodic materials are prepared by thermal decomposition method and the anodic kinetic parameters ( a,b,i 0) are determined in 1 mol/L H 2SO 4 solution. The SEM photographs of the electrodes are scanned and saved as a BMP image file, from which a three dimensional space with graph and grey scale is obtained. Then the fractal dimension of the electrodes is calculated by using the formula D B( F ) =log N δ(F )/-log δ and a calculation program. The electrocatalytic performance of the electrodes is discussed combining with the fractal dimension and kinetic parameters. The influences of the electrode composition on the kinetic parameters are also discussed according to the dual barrier model and mechanism of the oxygen evolution at oxide anodes. The results show that the larger fractal dimension of the electrodes is, the better electrocatalytic activity is.展开更多
文摘As a rapid uniform and efficient heating method, microwave irradiation has been widely used in chemical reaction and preparing nanomaterials. Here Pt/carbon nanotube(CNT) catalysts with w(Pt)=18.1% and 9.4 % were rapidly synthesized by microwave irradiation heating polyol process and employing the ethylene glycol solution of H 2PtCl 6 as the precursors in the presence of CNT support. TEM imaging showed that microwave-prepared Pt nanoparticles were very uniform in size, with an average size of 3.1 nm, and uniformly dispersed on the CNT surface. Electrochemical experiments demonstrated that microwave-synthesized Pt/CNT catalysts exhibited a higher catalytic activity for electrooxidation of liquid methanol than E-TEK Pt/C. The significant improvement in catalyst performance derives from that microwave-synthesized Pt nanoparticles have a uniform small particle size and uniforml dispersion on the CNT surface.
文摘Several Ti supported oxide anodic materials are prepared by thermal decomposition method and the anodic kinetic parameters ( a,b,i 0) are determined in 1 mol/L H 2SO 4 solution. The SEM photographs of the electrodes are scanned and saved as a BMP image file, from which a three dimensional space with graph and grey scale is obtained. Then the fractal dimension of the electrodes is calculated by using the formula D B( F ) =log N δ(F )/-log δ and a calculation program. The electrocatalytic performance of the electrodes is discussed combining with the fractal dimension and kinetic parameters. The influences of the electrode composition on the kinetic parameters are also discussed according to the dual barrier model and mechanism of the oxygen evolution at oxide anodes. The results show that the larger fractal dimension of the electrodes is, the better electrocatalytic activity is.
