Passivation of PEA(+) to MAPbI(3) (110) surface states by first-principles calculations
Passivation of PEA(+) to MAPbI(3) (110) surface states by first-principles calculations
复制标题
通过第一性原理计算将 PEA( ) 钝化为 MAPbI(3) (110) 表面态
DOI：
10.1088/1674-1056/abccb7
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发表时间：
2021
影响因子：
1.7
通讯作者：
Tang Fu-Ling
中科院分区：
文献类型：
--
作者：
Hu Wei;Tian Ying;Xue Hong-Tao;Li Wen-Sheng;Tang Fu-Ling
MAPBi3(110)面具有较低的晶面折射率，是一种稳定的、高度相容的光敏表面。由于表面的电子态可能不利于器件的光伏效率，因此它们应该被钝化。苯乙胺(PEA+)作为一种分子配体，在连续降解和界面电荷复合实验中得到了广泛的应用，在改善表面缺陷方面具有良好的性能。因此，我们建立了小分子MAPBi3的吸附模型，计算了PEA+吸附MAPBi3(110)表面的晶格结构和电子性质。结果表明，PEA+作为钝化剂可以有效地削弱MAPbI3(110)表面的电子态和调节其带隙。加入钝化剂前后，MAPBi3(110)表面的电子态密度峰值降低了约50%，禁带宽度明显减小。此外，通过比较PEA+S吸附在MAPBi3表面前后的Bader原子电荷和空间电荷分布，我们观察到PEA+电荷的实质性变化，这表明PEA+已经钝化了表面态。
The MAPbI 3 (110) surface with low indices of crystal face is a stable and highly compatible photosensitive surface. Since the electronic states on the surface can be detrimental to the photovoltaic efficiency of the device, they should be passivated. Phenylethylamine (PEA+), as a molecular ligand, has been widely used in continuous degradation and interfacial charge recombination experiments, and has satisfactory performance in improving surface defects. Therefore, we construct an adsorption model of MAPbI 3 with small molecules, calculating the lattice structure and electronic properties of PEA+-adsorbed MAPbI 3 (110) surface. It is found that PEA+ as a passivator can effectively weaken the electronic states and regulate the band gap of the MAPbI 3 (110) surface. Before and after adding the passivator, the peak value of electronic state densities at MAPbI 3 (110) surface is reduced by about 50%, and the band gap is apparently reduced. Moreover, by comparing the Bader atomic charge and spatial charge distributions before and after PEA+'s adsorption on the surface of MAPbI 3, we observe a substantial change of PEA+ charges, which suggests the surface states have been passivated by PEA+.