In this article, we successfully prepared the WO₃/g-C₃N₄ (WO/CN) heterojunction photocatalyst with high photocatalytic CO₂ reduction performance by the simple impregnation–calcination process. Transmission electron microscopy (TEM) analysis shows that the WO₃ nanoparticles (WO₃ NPs) are successfully attached to the g-C₃N₄ nanosheets (CN). UV–vis reflectance spectrum (UV–vis DRS), photoluminescence spectrum (PL), and photoelectrochemical (PEC) results confirm that the building of a WO/CN heterojunction is beneficial to the transfer and separation processes of the photogenerated carriers in the photocatalysts. The photoreduction performances of the obtained samples are indicated by the photocatalytic CO₂ reduction process under UV and visible light irradiation. These experiments prove that the 10-WO/CN photocatalyst has the best photoreduction performance compared to other obtained photocatalysts. The yields of CO and CH₄ in the presence of the 10-WO/CN photocatalyst are 8.9 and 47.7 times larger than those of pure CN under UV irradiation. For the irradiation of visible light, the yield rates of CO and CH₄ over 10-WO/CN are 8.6 and 7.5 times greater than those of the CN. On the basis of these photocatalytic results and electron spin resonance (ESR) results, the possible direct Z-scheme electron transfer mechanism for 10-WO/CN with the improved photoreduction CO₂ activity has been discussed.

中文翻译：

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直接Z方案WO ₃ /碳氮化碳纳米复合材料用于CO ₂的光还原

在本文中，我们通过简单的浸渍-煅烧过程成功制备了具有高光催化CO ₂还原性能的WO ₃ / gC ₃ N ₄（WO / CN）异质结光催化剂。透射电子显微镜（TEM）分析显示，WO ₃纳米颗粒（WO ₃ NPs）成功附着在gC ₃ N _4上纳米片（CN）。UV-vis反射光谱（UV-vis DRS），光致发光光谱（PL）和光电化学（PEC）结果证实，WO / CN异质结的构建有利于光催化剂中光生载流子的转移和分离过程。所得样品的光还原性能通过UV和可见光照射下的光催化CO ₂还原过程表示。这些实验证明，与其他获得的光催化剂相比，10-WO / CN光催化剂具有最佳的光还原性能。CO和CH ₄的产率在10-WO / CN光催化剂的存在下，在紫外线照射下，其纯度是纯CN的8.9和47.7倍。对于可见光的照射，在10-WO / CN上的CO和CH ₄的产率分别是CN的8.6和7.5倍。根据这些光催化结果和电子自旋共振（ESR）结果，讨论了具有改善的光还原CO ₂活性的10-WO / CN可能的直接Z方案电子转移机理。