Using solar energy to convert CO₂ into value-added fuel is crucial for the goal of global carbon neutrality. Effective separation of photogenerated charges is important for improving photocatalytic CO₂ reduction efficiency. Herein, we report a facile in situ exfoliation and conversion strategy to synthesize a novel CeO₂/C₃N₄ heterostructure by uniformly distributing CeO₂ nanoparticles onto ultrathin porous C₃N₄ nanosheets. The ultrathin porous structure of C₃N₄ not only increases the specific surface area to provide more active sites but also effectively shortens the migration distance of photogenerated electron holes to avoid their recombination. In addition, the well-dispersed CeO₂ on C₃N₄ shows an intimate interface contact, which allows more charges to be transferred through the increased interface surface area. The as-synthesized CeO₂/C₃N₄ heterojunction with well-matched band gaps and a Z-scheme structure prolongs the lifetime of photo-induced charge carriers and maximizes the redox ability of the photocatalyst. Without a noble metal cocatalyst or a sacrificial agent, the CO₂ photoreduction performance of the CeO₂/C₃N₄ heterojunction is approximately 5-fold enhanced compared with that of bulk C₃N₄. This study provides a facile strategy for the design and practical application of direct Z-scheme pho-tocatalysts for sustainable energy conversion.

使用太阳能将CO ₂转化为增值燃料对于实现全球碳中和的目标至关重要。有效分离光生电荷对于提高光催化CO ₂还原效率具有重要意义。在此，我们报告了一种简便的原位剥离和转化策略，通过将 CeO ₂纳米粒子均匀分布到超薄多孔 C ₃ N ₄纳米片上来合成新型 CeO ₂ /C ₃ N ₄异质结构。_{C 3} N ₄的超薄多孔结构不仅增加了比表面积以提供更多的活性位点，而且还有效地缩短了光生电子空穴的迁移距离，避免了它们的复合。此外，C ₃ N _{4上分散良好的 CeO 2}显示出紧密的界面接触，这允许更多的电荷通过增加的界面表面积转移。合成后的 CeO ₂ /C ₃ N ₄异质结具有良好匹配的带隙和 Z 型结构，可延长光生载流子的寿命并最大限度地提高光催化剂的氧化还原能力。在没有贵金属助催化剂或牺牲剂的情况下，CO ₂与体相C 3 N 4 相比，CeO 2 /C 3 N 4 异质结_的光_还原性能_提高了_大约5_倍。本研究为可持续能源转换的直接 Z 型光催化剂的设计和实际应用提供了一种简便的策略。