对合体 ZnO 纳米晶体的减少的阴离子效应
Carolyn N Valdez1, Murielle F Delley1, James M Mayer1
1Department of Chemistry , Yale University , New Haven , Connecticut 06520-8107 , United States.
Journal of the American Chemical Society
|June 20, 2018
概括
电离子通过电荷平衡电子稳定减少的氧化 (ZnO) 纳米晶体,影响它们的电子性质. 这一发现对于理解ZnO中的电荷储存及其与电池技术的关系至关重要.
科学领域:
- 材料科学
- 纳米技术
- 电化学
背景情况:
- 合氧化物 (ZnO) 纳米晶体 (NC) 是各种应用的有希望的材料.
- 了解ZnONC中的电荷存储机制对于开发新的电子设备至关重要.
- 对半导体纳米晶体电子特性的影响尚未完全理解.
研究的目的:
- 研究各种单原子和较大的离子对合 ZnO 纳米晶体的减少的影响.
- 量化NC减少的程度,并了解电荷稳定中的离子的作用.
- 将 ZnO NC 的体化学与散装氧化物半导体和电池技术联系起来.
主要方法:
- 在烯/THF悬浮液中制备"TOPO"覆盖的 ZnO NC.
- 用单电子还原剂 (CoCp*2或离子基) 和各种离子对NC悬浮进行处理.
- 通过测量导电带电子的近红外吸收率来量化NC减小.
主要成果:
- 发现 (H +,Li +,Na +,K +,Mg2 +,Ca2 +,十甲基,四甲基) 影响了 ZnO NC 减少的程度.
- 电子通过静电学转移到ZnONCs,电荷平衡通过阳离子 (1个单价阳离子电子,2个双价阳离子).
- 每个ZnONC的最大电子吸收取决于NC体积和离子类型,表明离子依赖的电荷储存.
结论:
- 在ZnO纳米晶体中充电平衡添加的电子中发挥着关键作用.
- 体ZnO的明显带能受到阳离子/电解质组成和度的显著影响.
- ZnO NC中的电荷存储机制类似于离子电池,突出显示了储能应用的潜力.
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