在聚合聚合物中将追踪电荷转移到剩余金属集群中,以实现光催化演变
Michael Sachs1, Hyojung Cha1, Jan Kosco2
1Department of Chemistry and Centre for Processable Electronics, Imperial College London, 80 Wood Lane, London W12 0BZ, U.K.
Journal of the American Chemical Society
|August 14, 2020
概括
带有 (Pd) 集群的半导体聚合物表现出不同的生产活性. 优化聚合物光催化剂需要平衡快速激发和高效的电荷转移到金属共催化剂,以提高太阳能转化率.
科学领域:
- 材料科学
- 光催化
- 可再生能源
背景情况:
- 半导体聚合物对太阳能转化和光催化生产具有前景.
- 有机聚合物中的残留 (Pd) 集群可以在光催化中发挥催化作用.
研究的目的:
- 调查集度和电子转移动态对半导体聚合物的演变活性的影响.
- 阐明F8BT和P10聚合物纳米粒子中激子火和电荷定位的机制.
主要方法:
- 在F8BT,P3HT和P10聚合物纳米粒子上使用过渡式和操作式光谱学.
- 分析的重点是与残留度相关的电子转移时间尺度和定位.
主要成果:
- 在F8BT中的Pd集群在5纳秒的时间尺度上灭激子,限制高度 (>1000ppm) 的进化.
- 由于高效的还原性火和较慢的电子转移到Pd集群,P10表现出更高的演变活性,即使在高Pd度 (27000 ppm) 中,电子也会定位在聚合物上.
- 随着F8BT中的Pd含量减少,电子定位从Pd集群转移到聚合物中.
结论:
- 有效的聚合物光催化剂需要快速的还原性火和快速的电荷转移到金属共催化剂.
- 材料设计应专注于优化激电动力学和电荷传输路径,以改善的生产.
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