连续减少高化物计数的八面体团[Rh6(PR3) 6H12][BArF4]2:可回氧切换的储存
Simon K Brayshaw1, Andrew Harrison, J Scott McIndoe
1Department of Chemistry, University of Bath, BA2 7AY, UK.
Journal of the American Chemical Society
|February 8, 2007
概括
这项研究探讨了用于储存的团,证明了可逆的H2吸收和释放机制. 这些集群提供了一种新的电子触发方法,用于在温和条件下储存气.
科学领域:
- 无机化学 无机化学
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
背景情况:
- 八面体的团与桥接化物连接物,[Rh6(PR3) 6H12][BArF4]2,表现出复杂的氧化还原行为.
- 以前的研究已经探索了相关的化团,但高效的储存仍然是一个挑战.
研究的目的:
- 研究新型八面体团的氧化还原特性和储存能力.
- 描述在氧化还原过程中形成的基性和磁性物种.
- 评估这些集群在环境条件下可逆储存的潜力.
主要方法:
- 使用循环电压测量来确定团的可访问的氧化还原状态.
- 使用过渡金属复合物 (Cr(arene) 2 ,Co(Cp) 2) 的化学氧化和还原被用来分离特定物种.
- 使用X射线晶体学,电子喷射质谱学 (ESI-MS),电子磁共振 (EPR),核磁共振 (NMR) 和SQUID磁力学进行了结构性和磁性表征.
主要成果:
- 确定了四个氧化还原状态 ([Rh6(PR3) 6H12]0/1+/2+/3+) 的集群.
- 稳定的单离子基 ([Rh6(PR3) 6H12]+,S=1/2) 和中性偏磁性 (iPr-[H12],S=1) 物种被分离和特征化.
- 可逆吸收和释放的H2 (2等值). 通过一电子氧化还原开关实现,分别形成[Rh6(PR3) 6H14]+和[Rh6(PR3) 6H12]物种.
结论:
- 团展示了一种简单且可重复使用的储存方法,由单电子氧化还原过程驱动.
- 观察到的H2吸收和释放在温和条件下 (室温和压力) 发生,动力学快速.
- 虽然目前的储能能力较低,但其独特的特性表明未来储应用的潜力.
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