首页> 美国卫生研究院文献>Proceedings of the National Academy of Sciences of the United States of America >Energy transfer-enhanced photocatalytic reduction of protons within quantum dot light-harvesting–catalyst assemblies
【2h】

Energy transfer-enhanced photocatalytic reduction of protons within quantum dot light-harvesting–catalyst assemblies

机译:量子点集光催化剂组件中质子的能量转移增强光催化还原

代理获取
本网站仅为用户提供外文OA文献查询和代理获取服务,本网站没有原文。下单后我们将采用程序或人工为您竭诚获取高质量的原文,但由于OA文献来源多样且变更频繁,仍可能出现获取不到、文献不完整或与标题不符等情况,如果获取不到我们将提供退款服务。请知悉。

摘要

Excitonic energy transfer (EnT) is the mechanism by which natural photosynthetic systems funnel energy from hundreds of antenna pigments to a single reaction center, which allows multielectron redox reactions to proceed with high efficiencies in low-flux natural light. This paper describes the use of electrostatically assembled CdSe quantum dot (QD) aggregates as artificial light harvesting–reaction center units for the photocatalytic reduction of H+ to H2, where excitons are funneled through EnT from sensitizer QDs (sQDs) to catalyst QDs (cQDs). Upon increasing the sensitizer-to-catalyst ratio in the aggregates from 1:2 to 20:1, the number of excitons delivered to each cQD (via EnT) per excitation of the system increases by a factor of nine. At the optimized sensitizer-to-catalyst ratio of 4:1, the internal quantum efficiency (IQE) of the reaction system is 4.0 ± 0.3%, a factor of 13 greater than the IQE of a sample that is identical except that EnT is suppressed due to the relative core sizes of the sQDs and cQDs. A kinetic model supports the proposed exciton funneling mechanism for enhancement of the catalytic activity.
机译:激子能量转移(EnT)是一种机制,自然光合作用系统将能量从数百种天线色素转移到单个反应中心,从而使多电子氧化还原反应能够在低通量自然光下高效地进行。本文介绍了使用静电组装的CdSe量子点(QD)聚集体作为人工光收集-反应中心单元,将H + 光催化还原为H2的过程,其中激子通过EnT从敏化剂QD漏斗( sQDs)转换为催化剂QDs(cQDs)。在将聚集体中的敏化剂/催化剂比例从1:2增加到20:1时,系统每次激发传递到每个cQD(通过EnT)的激子数量增加了九倍。在优化的增感剂与催化剂的比例为4:1的情况下,反应系统的内部量子效率(IQE)为4.0±0.3%,比相同样品的IQE大13倍,除了EnT被抑制由于sQD和cQD的相对核心大小。动力学模型支持所提出的激子漏斗机制以增强催化活性。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
代理获取

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