Solar-energy-driven CO₂ conversion into high-valued fuels has been considered as a promising strategy to alleviate the greenhouse effect and energy crisis problems. However, the rapid charge recombination, poor light utilization and low selectivity, etc. still limit the efficiency of photocatalytic CO₂ reduction. In this work, a novel 2D/2D Bi₂Se₃/g-C₃N₄ heterojunction composite has been developed to investigate the improved photocatalytic activity towards CO₂ reduction selectively. Fortunately, an intimate interaction was formed between 2D Bi₂Se₃ and 2D g-C₃N₄, which is very beneficial for the charge separation and transfer. In this composite, Bi₂Se₃ not only acted as a cocatalyst liked role, but also played as an extra heater for photocatalytic reaction by effective photo-to-heat conversion. As expected, the 2D/2D Bi₂Se₃/g-C₃N₄ composite presented much improved photocatalytic ability for CO₂ reduction to CO, which is about 6.3 times higher than that of pristine g-C₃N₄ under the irradiation of full spectrum. Notably, the product from CO₂ reduction was nearly 100% CO without other carbon products, and the selectivity for CO was greater than 90% over H₂ evolution. The experimental tests and DFT calculations confirmed that the superiority of photocatalytic CO₂ reduction ability of Bi₂Se₃/g-C₃N₄ composite over other counterparts should be attributed to the synergetic effect of highly improved charge separation and strong photo-to-heat conversion efficiency. Meanwhile, the CO₂ reduction process was studied by in-situ FTIR in detail. The as-proposed composite in this work might provide a potential strategy for developing high efficiency of photocatalytic CO₂ reduction to valuable fuels.

太阳能驱动的CO ₂转化为高价值燃料已被认为是缓解温室效应和能源危机问题的有前途的战略。但是，快速的电荷复合，光利用率差和选择性低等仍然限制了光催化CO ₂还原的效率。在这项工作中，已开发出一种新颖的2D / 2D Bi ₂ Se ₃ / gC ₃ N ₄异质结复合材料，以研究对CO ₂还原选择性提高的光催化活性。幸运的是，在2D Bi ₂ Se ₃和2D gC ₃ N ₄之间形成了紧密的相互作用。，这对电荷的分离和转移非常有利。在这种复合物中，Bi ₂ Se ₃不仅起到助催化剂的作用，而且还通过有效的光热转换充当光催化反应的额外加热器。如所预期的，2D / 2D Bi ₂ Se ₃ / gC ₃ N ₄复合材料表现出大大提高的将CO ₂还原为CO的光催化能力，在全光谱辐射下比原始gC ₃ N ₄高约6.3倍。值得注意的是，CO ₂的产物在没有其他碳产物的情况下，CO的还原率几乎为100％，并且在H ₂放出过程中，CO的选择性大于90％。实验测试和DFT计算证实，Bi ₂ Se ₃ / gC ₃ N ₄复合材料的光催化CO ₂还原能力优于其他复合物的原因应归功于高度改进的电荷分离和强大的光热转换的协同效应。效率。同时，通过原位FTIR对CO _2的还原过程进行了详细的研究。这项工作中提议的复合材料可能为开发高效率的光催化CO ₂提供潜在的策略。 减少到有价值的燃料。