...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>The journal of physical chemistry, B. Condensed matter, materials, surfaces, interfaces & biophysical >Suppression of Nitrogen Oxide Dissociation by Gold on Pt(335)
【24h】

Suppression of Nitrogen Oxide Dissociation by Gold on Pt(335)

机译：金在Pt（335）上抑制一氧化氮的离解

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Prototype NOx s.ensors for use in automotive exhaust can contain Au/Pt electrodes that dissociate 0_2 for removal by electrochemical pumping, but these electrodes sho1,1ld not dissociate NO. In these sensors, the NO diffuses to a second chamber where it is then detected. To understand the process that occurs at the Au/Pt electrode we have used temperature-programmed desorption to study the dissociation of NO and 0_2 on Pt(335) and on partially Au covered Pt(335). With a gold coverage ofo.15 ML, the dissociation probability of NO is decreased by a factor of 5 relative to bare Pt. Increasing Au coverage to 0.3 ML decreases NO dissociation to an undetectable level. At 0.3 ML Au, the saturation coverage of atomic 0 is reduced by only 20%. The variation of NO dissociation with Au coverage occurs in the range where all of the Au atoms are at steps, but Au is more effective at decreasing NO dissociation than can be explained by a simple site- blocking model. The effect of adsorbed 0 on NO dissociation was also investigated. Both Au and 0 decrease NO dissociation, but Au is much more effective. Blocking 40% of the step sites with 0 reduces NO dissociation by 70%-more than site-blocking, but much less than a comparable coverage of Au. Our observations show how the Au/Pt electrode in a NOx sensor is able to dissociate oxygen approx 10~3 times more efficiently than NO.
机译：用于汽车尾气的NOx传感器原型可以包含Au / Pt电极，该电极可解离0_2以通过电化学泵去除，但这些电极均不能解离NO。在这些传感器中，NO扩散到第二腔，然后在第二腔中对其进行检测。为了了解在Au / Pt电极上发生的过程，我们使用了程序升温脱附技术来研究NO和0_2在Pt（335）和部分被Au覆盖的Pt（335）上的解离。金覆盖率为15 ML时，NO的解离概率相对于裸Pt降低了5倍。将Au覆盖率提高到0.3 ML可以将NO离解降低到无法检测的水平。在0.3 ML Au时，原子0的饱和覆盖率仅降低20％。 NO解离度随Au覆盖率的变化发生在所有Au原子都处于台阶的范围内，但是Au在降低NO解离度方面比通过简单的位阻模型可以解释的更为有效。还研究了吸附的0对NO离解的影响。 Au和0都降低NO离解，但Au更有效。用0阻断40％的阶梯位点将使NO离解比阻止位点减少70％，但远小于可比的Au覆盖率。我们的观察结果表明，NOx传感器中的Au / Pt电极如何能比NO分解氧效率高约10〜3倍。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号