Inspired by the carbon cycle in nature, it is promising to convert CO₂ into energy-dense hydrocarbon fuels via photocatalytic CO₂ reduction. In the present paper, hierarchical ZnMn₂O₄/ZnO nanofibers were prepared as photocatalysts by electrospinning and calcination. They outperformed pristine ZnO nanofibers with about 4-fold increment in CO and CH₄ yields. Except for the advantages coming from the design, such as more exposed active sites and multiple light reflections, other benefits derived from interface charge transfer are also important. To uncover this, density functional theory calculation (DFT), along with X-ray photoelectron spectroscopy (XPS) was performed. Photoluminescence (PL) and time-resolved PL spectroscopy revealed that the charge separation efficiency in the composite was significantly elevated. Step-scheme (S-scheme) charge transfer was testified in the composite. This result, for the first time, exemplifies that S-scheme charge-transfer can also be realized in heterojunction based-on p-type ZnMn₂O₄ and n-type ZnO. It provides a new insight into the design of other S-scheme photocatalysts, which are composed of p-type and n-type semiconductors.

受自然界中碳循环的启发，有望通过光催化还原CO ₂将CO ₂转化为能量密集的烃类燃料。本文通过静电纺丝和煅烧制备了层状ZnMn ₂ O ₄ / ZnO纳米纤维作为光催化剂。它们的原始性能优于原始ZnO纳米纤维，CO和CH _4的增量约为4倍产量。除了设计带来的好处（例如，更多的暴露的活性位点和多次光反射）外，从界面电荷转移中获得的其他好处也很重要。为了揭示这一点，进行了密度泛函理论计算（DFT）以及X射线光电子能谱（XPS）。光致发光（PL）和时间分辨的PL光谱显示，复合材料中的电荷分离效率显着提高。在复合材料中证明了分步方案（S方案）的电荷转移。该结果首次例示了在基于p型ZnMn ₂ O _4的异质结中也可以实现S方案电荷转移和n型ZnO。它为其他由p型和n型半导体组成的S型光催化剂的设计提供了新的见识。