We synthesize ZnS–ZnO heterostructure nanorings at ∼680 °C under carrier gases with various [CO₂]/[N₂] ratios simulating an anoxic and weakly reduced atmosphere on early Earth. The synthesized nanorings consist of a ZnS–ZnO bilayered stem, ZnO teeth, and ZnS wing-like structures between the teeth and the ZnS layer. O atoms are supplied through the decomposition of CO₂ presumably catalyzed by the ZnS surface. The respective growth directions of ZnS and ZnO layers in the stem are [0001] and [011̅1], and ZnO teeth are directed outward from the ring. The nanorings are structurally different from ZnS–ZnO nanorings having inward-directed teeth, which were grown under an oxygen-containing ambient environment. Contrary to the assumption of sulfide dominance including ZnS and MnS while disregarding oxygen-containing minerals such as ZnO on early Earth, we show that ZnS–ZnO nanorings, which are more advantageous in CO₂ reduction efficiency, could be formed.

中文翻译：

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在可能的早期地球大气下生长的ZnS–ZnO异质结构纳米环

我们在〜680°C的载气下以各种[CO ₂ ] / [N ₂ ]比率合成了ZnS–ZnO异质结构纳米环，以模拟地球早期的缺氧和弱还原性大气。合成的纳米环由ZnS-ZnO双层茎，ZnO齿以及在齿和ZnS层之间的ZnS翼状结构组成。通过分解CO ₂来提供O原子大概是由ZnS表面催化的。茎中ZnS和ZnO层的生长方向分别为[0001]和[011̅1]，并且ZnO齿从环中向外指向。纳米环在结构上与具有向内齿的ZnS–ZnO纳米环不同，后者在含氧的环境下生长。与不考虑地球早期的含氧矿物（如ZnO）而假设的硫化物占主导地位的ZnS和MnS相反，我们证明可以形成ZnS-ZnO纳米环，该环在降低CO ₂效率方面更具优势。