| ²é¿´: 732 | »Ø¸´: 1 | ||
| ±¾Ìû²úÉú 1 ¸ö ·ÒëEPI £¬µã»÷ÕâÀï½øÐв鿴 | ||
±¦MMC½ð³æ (СÓÐÃûÆø)
|
[ÇóÖú]
°ïæ·Ò뻯ѧÎÄÏ×ÖеÄÓ¢ÎÄ Ó¢Ò뺺10-11
|
|
|
10. The COad stripping voltammograms for Pt/C and Pt/CrN, seen in Figure 5a and b, respectively, show that the onset andpeak potentials toward CO ad oxidation on Pt/CrN are more negative than those observed for CO ad oxidation on Pt/C. The onset potential for CO ad oxidation was 0.40 V (vs SCE) for Pt/CrN and 0.48 V (vs SCE) for Pt/C, while the peak potential for COad oxidation was 0.51 V (vs SCE) for Pt/CrN and 0.53 V (vs SCE) for Pt/C. This indicates that Pt/CrN has a greater ECSA than Pt/C for CO oxidation, and thus Pt/CrN has greater intrinsic catalytic surface area than Pt/C. The actual ECSAs that were calculated from the CO ad oxidation charge after subtracting the background current were 82 and 75 m 2 /g for Pt/CrN and Pt/C, respectively. These values are also consistent with the average Pt particle sizes observed for the Pt/CrN and Pt/C catalysts. 11. The cyclic voltammograms of Pt/CrN and Pt/C seen in Figure 6a show that the onset potential of Pt/CrN toward methanol oxidation (0.20 V vs SCE) is more negative than that of Pt/C (0.22 V vs SCE), indicating that Pt/CrN has slightly greater catalytic activity for methanol electrooxidation. Furthermore, the peak current density for methanol oxidation on Pt/CrN is 195 mA mg−1 Pt, which is higher than the peak current density on Pt/C (145 mA mg−1 Pt). The specific activities of the two catalysts were also calculated as specific current normalized to the ECSA of each catalyst. The specific activity for Pt/CrN was 2.4 A/m2 of catalyst surface area, and the specific activity for Pt/C was 1.9 A/m2 of catalyst surface area. Finally, the plot of polarization current versus time measured at 0.6 V for each catalyst can be seen in Figure 6b. The Pt/CrN catalyst showed both a significantly slower deterioration rate and a higher steady-state current than the carbon-supported catalyst tested. Thus, we can conclude that the Pt/CrN catalyst has higher tolerance to poison in the electrolyte solution than the Pt/C catalyst. A summary of the electrochemical measurements obtained for the two catalysts can be seen in Table 1. |
» ²ÂÄãϲ»¶
080500Çóµ÷¼Á
ÒѾÓÐ5È˻ظ´
269µç×ÓÐÅÏ¢Çóµ÷¼Á£¬¿Éתרҵ
ÒѾÓÐ5È˻ظ´
285Çóµ÷¼Á
ÒѾÓÐ15È˻ظ´
265Çóµ÷¼Á
ÒѾÓÐ8È˻ظ´
274Çóµ÷¼ÁÇóµ÷¼Á
ÒѾÓÐ5È˻ظ´
284Çóµ÷¼Á
ÒѾÓÐ4È˻ظ´
ÍÁľˮÀûר˶276·ÖÇóµ÷¼Á
ÒѾÓÐ4È˻ظ´
²ÄÁÏ¿¼ÑÐÇóµ÷¼Á×Ü·Ö280
ÒѾÓÐ9È˻ظ´
285Çóµ÷¼Á
ÒѾÓÐ6È˻ظ´
²ÄÁϵ÷¼Á
ÒѾÓÐ9È˻ظ´
RXMCDM
°æÖ÷ (ÎÄ̳¾«Ó¢)
- ·ÒëEPI: 530
- Ó¦Öú: 401 (˶ʿ)
- ¹ó±ö: 1.908
- ½ð±Ò: 38947.6
- É¢½ð: 4908
- ºì»¨: 88
- ɳ·¢: 4
- Ìû×Ó: 11453
- ÔÚÏß: 1355.6Сʱ
- ³æºÅ: 2739168
- ×¢²á: 2013-10-20
- ÐÔ±ð: GG
- רҵ: Ò»°ã¹ÜÀíÀíÂÛÓëÑо¿·½·¨ÂÛ
- ¹ÜϽ: ÂÛÎÄ·Òë
¡¾´ð°¸¡¿Ó¦Öú»ØÌû
¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï ¡ï
±¦MMC: ½ð±Ò+45, ·ÒëEPI+1, ¡ï¡ï¡ïºÜÓаïÖú, ·Ç³£¸Ðл! ÕâÆªÎÄÏ×·ÒëÍê³ÉÁË£¬Ï£ÍûÏ´ÎÄܹ»¼ÌÐøºÏ×÷£¡ 2013-12-02 20:47:58
±¦MMC: ½ð±Ò+45, ·ÒëEPI+1, ¡ï¡ï¡ïºÜÓаïÖú, ·Ç³£¸Ðл! ÕâÆªÎÄÏ×·ÒëÍê³ÉÁË£¬Ï£ÍûÏ´ÎÄܹ»¼ÌÐøºÏ×÷£¡ 2013-12-02 20:47:58
|
10¡£COÎü¸½µÄPt / CºÍPt /µª»¯¸õÈܳö·ü°²Í¼£¬·Ö±ð¼ûͼ5aºÍb£¬ÏÔʾÁËCOÔÚPt /µª»¯¸õµÄÎü¸½Ñõ»¯·¢×÷ºÍ·åµçλ±È¹Û²ìµ½µÄCOÔÚPt/ CµÄÎü¸½Ñõ»¯¸üµÍ¡£COÔÚPt /µª»¯¸õµÄÎü¸½Ñõ»¯·¢×÷µçλΪ0.40 V (Ïà¶ÔÓÚSCE)£¬ÔÚPt/CΪ 0.48 V (Ïà¶ÔÓÚSCE) ¡£¶øCOÔÚPt /µª»¯¸õµÄÎü¸½Ñõ»¯·æÖµµçλΪ0.51 V (Ïà¶ÔÓÚSCE)£¬ÔÚPt/CΪ 0.53V (Ïà¶ÔÓÚSCE).±íÃ÷£¬²¬/µª»¯¸õCOÑõ»¯·´Ó¦¾ßÓбȵÄPt / C COÑõ»¯·´Ó¦¸ü´óµÄECSA£¬´Ó¶ø²¬/µª»¯¸õ¾ßÓбÈPt/ C¸ü´óµÄÄÚÔÚ´ß»¯±í̾̾»ý¡£Êµ¼ÊECSAͨ¹ýCOÎü¸½Ñõ»¯µçºÉ¼õÈ¥±³¾°µçÁ÷ºó¼ÆËã³ö£¬Pt /µª»¯¸õºÍPt/ C·Ö±ðΪ82ºÍ75ƽ·½Ã×/¿Ë¡£ÕâЩֵҲÓë¹Û²ìµ½µÄPt /µª»¯¸õºÍPt / C´ß»¯¼ÁµÄƽ¾ùPtÁ£¾¶Ò»Ö¡£ 11¡£Í¼6aµÄPt /µª»¯¸õºÍPt/ CÑ»··ü°²ÇúÏ߿ɿ´³ö£¬Pt/µª»¯¸õ¶Ô¼×´¼Ñõ»¯£¨0.20 VÓëSCE£©µÄ·¢×÷µçλ±ÈµÄPt / C£¨0.22 VÓëSCE£©¸üµÍ£¬±íÃ÷µÄPt/µª»¯¸õ¶Ô¼×´¼¾ßÓнϴóµÄµç´ß»¯»îÐÔ¡£´ËÍ⣬Pt /µª»¯¸õ¶Ô¼×´¼Ñõ»¯µÄ·åÖµµçÁ÷ÃܶÈΪÊÇ195ºÁ°²Ã¿ºÁ¿ËPt£¬±ÈPt / C¸ß£¨145ºÁ°²Ã¿ºÁ¿ËPt£©¡£Á½ÖÖ´ß»¯¼ÁµÄ¾ßÌå´ß»¯»îÐÔͨ¹ý¾ßÌåµçÁ÷±ê»¯ÎªÃ¿ÖÖ´ß»¯¼ÁµÄECSA£¬²¬/µª»¯¸õµÄ¾ßÌå»îÐÔΪ2.4°²Æ½·½Ã×´ß»¯¼Á±íÃæ»ý£¬Pt / CµÄ¾ßÌå»îÐÔΪ1.9°²Æ½·½Ã×´ß»¯¼Á±íÃæ»ý¡£×îºó£¬Í¼6b¿É¿´³ö£¬Ã¿ÖÖ´ß»¯¼Á¼«»¯µçÁ÷µÄÓëʱ¼äµÄ»ýΪ0.6 V ¡£Pt/µª»¯¸õ´ß»¯¼Á±È̼¸ºÔصĴ߻¯¼Áͬʱ¾ßÓнÏÂýµÄÍË»¯ÂʺͽϸߵÄÎÈ̬µçÁ÷¡£±í1ÊÇÕâÁ½ÖÖ´ß»¯¼ÁµÄµç»¯Ñ§²âÁ¿µÄ×ܽᡣ |

2Â¥2013-12-02 19:47:16














»Ø¸´´ËÂ¥