空位排序双矿 [N(CH3) 4]2SnX6 (X=Cl, Br, I):热相过渡和广泛的光学吸收
Nagale S Vishwajith1, Ajay J Prasad1, Digvijay Narayan Singh2,3
1New Chemistry Unit, International Centre for Materials Science, School of Advanced Materials, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore, 560064, India.
四甲基化双矿, (TMA) 2SnX6,表现出可调节的带隙和热相过渡. 这些特性使得它们在太阳能和热能储能应用中非常有前途.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 晶体学 晶体学是指结晶学.
背景情况:
- 研究的是空位排序的化物双矿 (VODP) 的一般式 (TMA) 2SnX6,其中TMA是四甲基,X是化物 (Cl, Br, I).
- 这些化合物具有A位点的TMA+,M位点的Sn4+和化位点的化离子.
研究的目的:
- 为了合成和描述新的 (TMA) 2SnX6化合物,特别是 (TMA) 2SnCl0.7Br5.3和 (TMA) 2SnI6.6化合物.
- 为了研究 (TMA) 2SnCl6, (TMA) 2SnBr6, (TMA) 2SnCl0.7Br5.3和 (TMA) 2SnI6.6的结构相变.
- 探索化物组成对电子和光学特性的影响,特别是带隙和颜色.
主要方法:
- 合成四甲基化二重矿.双重矿.
- 在室温下进行结构确定的X射线晶体学.
- 差分扫描热量计 (DSC) 用于检测热相转换.
- 紫外线-Vis光谱法用于确定光学带间隙.
主要成果:
- 所有四种研究的化物, (TMA) 2SnCl6, (TMA) 2SnCl0.7Br5.3, (TMA) 2SnBr6和 (TMA) 2SnI6,在室温下结晶成立方Fdc对称.
- (TMA) 2SnCl6和 (TMA) 2SnBr6在364 K和369 K分别经历相位过渡到立方Fm对称.
- 报告了 (TMA) 2SnCl0.7Br5.3和 (TMA) 2SnI6的新合成和结构数据,分别在363 K和325 K观察到可逆过渡.
- 对 (TMA) 2SnCl6, (TMA) 2SnBr6的2.64 eV和 (TMA) 2SnI6的1.12 eV的光学带隙被确定为3.60 eV,在UV-Vis-NIR频谱中显示出广泛的可调性.
结论:
- 该研究成功合成和表征了新型 (TMA) 2SnX6化合物,扩大了VODPs的库.
- 观察到的热相转换和可调节的带隙凸显了这些材料在热和太阳能储能应用中的潜力.
- 化物联体在确定电子和光学性质方面发挥着至关重要的作用,使其能够为特定应用进行微调.
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