利用太陽能將二氧化碳轉化為碳氫燃料，是一種有望同時解決全球暖化和能源供應問題的方式。本研究以Sn2P2S6作為光催化劑，進行二氧化碳還原反應。Sn2P2S6做為二維材料中過渡金屬硫化物的一員，具有合適的能帶結構，可以吸收可見光以進行二氧化碳的還原。其較大的表面積也為吸附二氧化碳帶來許多活性位點。此外，層狀結構也使得光生電子-電洞對可以快速遷移至表面進行反應。綜合以上優點，我們認為Sn2P2S6擁有光催化二氧化碳還原的潛力。而光催化結果顯示，Sn2P2S6對於甲烷有高的選擇性，產率為33.90 μmol g-1 (6h)。缺陷工程是目前改善光催化劑效果的重大策略之一。通過引入缺陷，我們可以有效調節材料內部的電子結構，改善材料吸收可見光的範圍，並降低電子與電洞的再結合。除此之外，還能為材料表面帶來更多的活性位點。本研究以高溫加熱的方式在Sn2P2S6表面引入硫缺陷，以增強光催化劑的效果。實驗結果顯示，在引入缺陷後，光催化劑的效率提高到47.60 μmol g-1 (6h)，相較於原始的Sn2P2S6催化劑效果更好。另外，先前文獻提出，引入缺陷可導致材料產生自旋極化的現象。因此，我們透過加入磁場的方式進一步增加自旋極化的電子，進而提高光催化的效果，最終產率達到57.52 μmol g-1 (6h)。

Converting carbon dioxide into hydrocarbon fuels using solar energy is a promising approach to simultaneously address global warming and energy supply issues. In this study, Sn2P2S6 was used as a photocatalyst for the reduction of carbon dioxide. As a member of two-dimensional transition metal sulfides, Sn2P2S6 has a suitable band structure to absorb visible light for carbon dioxide reduction and its large surface area provides numerous active sites for carbon dioxide adsorption. Additionally, its layered structure facilitates the rapid migration of photogenerated electron-hole pairs to the surface for reactions. Based on the above advantages, we believe that Sn2P2S6 has great potential as a photocatalyst. The photocatalytic results showed that Sn2P2S6 exhibited high selectivity for methane with a yield of 33.90 μmol g-1 (6h). Defect engineering is a significant strategy to improve the performance of photocatalysts. By introducing defects, we can effectively modulate the electronic structure, enhance visible light absorption, and reduce electron-hole recombination. Moreover, it can introduce more active sites on the material's surface. In this study, we introduced sulfur defects on the surface of Sn2P2S6 through high-temperature heating to enhance the photocatalyst's efficiency. Experimental results demonstrated that the efficiency of the photocatalyst increased to 47.60 μmol g-1 (6h) after defect introduction, which is better than that of the pristine Sn2P2S6. Furthermore, previous literature has proposed that defect introduction can induce spin polarization. Therefore, we further increased spin-polarized electrons by introducing a magnetic field, thereby improving the photocatalytic effect, and the final yield reached 57.52 μmol g-1 (6h).

NASA Climate Change Vital Signs Carbon Dioxide. https://climate.nasa.gov/vital-signs/carbon-dioxide/
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