A series of CuO clusters/MIL-100(Fe) heterojunctions with different CuO mass ratios were constructed as the photocatalysts for N fixation. An optimal nitrogen fixation performance of 51.22 μmol·g·h is achieved when the mass fraction of CuO is 20 %. Isotope analysis experiments confirmed that the nitrogen source is N. Possible intermediate signals during photocatalytic reactions were detected by in situ DRIFTS. XPS results further confirm the formation of CuO/MIL-100(Fe) heterojunctions, and that the existence of Cu–O surface interactions is the key to efficient electron transfer. It is revealed that the improvement of the catalytic performance is derived from the formation of heterojunction which regulates the energy band structure as well as promotes the separation of photogenerated electron-hole pairs. This study proposes a possible mechanism of photocatalytic nitrogen fixation and emphasizes the role of surface interaction and electron transfer in type-II heterojunction in improving nitrogen fixation performance.

中文翻译：

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Cu2O簇/MIL-100(Fe)异质结增强光催化固氮


构建了一系列不同CuO质量比的CuO簇/MIL-100(Fe)异质结作为固氮光催化剂。当CuO质量分数为20%时，最佳固氮性能为51.22 μmol·g·h。同位素分析实验证实氮源为N。通过原位DRIFTS检测到光催化反应过程中可能的中间信号。 XPS结果进一步证实了CuO/MIL-100(Fe)异质结的形成，并且Cu-O表面相互作用的存在是有效电子转移的关键。研究表明，催化性能的提高源于异质结的形成，异质结调节能带结构并促进光生电子-空穴对的分离。本研究提出了光催化固氮的可能机制，并强调了II型异质结中的表面相互作用和电子转移在改善固氮性能中的作用。