ABSTRACT

SnO₂@SnS₂ multi-core–shell heterostructures were synthesised via chemical conversion of mesoporous raspberry-like SnO₂ nanocrystals. In the syntheses, different concentrations of a sulphide precursor (thioacetamide) were applied. The samples were analysed using scanning and high-resolution transmission electron microscopy, X-ray diffraction, Raman spectroscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. The results revealed the presence of surface defects (Sn²⁺, oxygen vacancies) on the raspberry-like surface, which play a crucial role in the chemical conversion reaction. With an increasing amount of thioacetamide, additional redox reactions occurred in the system (Sn⁴⁺/Sn²⁺, S²⁻/S⁰). The highest precursor concentration led to the microstructural disintegration and phase composition change.

摘要

SnO ₂ @SnS ₂多核壳异质结构是通过介孔覆盆子状SnO ₂纳米晶体的化学转化合成的。在合成中，应用了不同浓度的硫化物前体（硫代乙酰胺）。使用扫描和高分辨率透射电子显微镜、X 射线衍射、拉曼光谱、能量色散 X 射线光谱和 X 射线光电子能谱分析样品。结果表明，覆盆子状表面存在表面缺陷（Sn ²⁺，氧空位），这在化学转化反应中起着至关重要的作用。随着硫代乙酰胺量的增加，系统中发生了额外的氧化还原反应（Sn ⁴⁺ /Sn²⁺ , S ^{2 -} /S ⁰ )。最高的前体浓度导致微观结构崩解和相组成变化。