Designing and fabrication of smart hybrid multifunctional materials for energy/fuel production and environmental detoxification is indeed of great significance for sustainable development. Herein, we synthesized a new well-structured S-scheme heterostructure Fe@TiO₂/Boron Carbon nitride (FT/BCN) with high performance tetracycline degradation and selective CO₂ photo-reduction to CH₄. Under visible light irradiation, 96.3% tetracycline was degraded in 60 min using best performing FT30/BCN sample with a high 83.2% total organic carbon removal in 2 h. The tetracycline degradation rate for FT30/BCN composite catalyst was ∼7 times than bare boron carbon nitride (BCN). The impact of reaction parameters as pH, presence of interfering electrolytes, light source and water matrix was also investigated. The FT30/BCN photocatalyst shows dramatic improvement in CO₂ photoreduction as exhibited in 24.7 μmol g⁻¹ h⁻¹ CH₄ and 2.4 μmol g⁻¹ h⁻¹ CO evolutions with optimal 91.1% CH₄ selectivity. Pure BCN shows a poor 39.1% selectivity. Further, effect of alkali activation, CO₂/H₂O feed ratio, reducing agent and light source onto CH₄ production and selectivity was also investigated. The CH₄ evolution and selectivity was improved because of enhanced visible light absorption, high adsorption potential, charge carrier separation and high reducing power of photogenerated electrons induced by an effective S-scheme heterojunction between Fe@TiO₂ and boron carbon nitride. An S-scheme (step-scheme) charge transfer mechanism is here operative both during tetracycline removal and CO₂ reduction. The drug degradation route and photocatalytic mechanism for antibiotic removal and CO₂ reduction was also predicted.

设计和制造用于能源/燃料生产和环境解毒的智能混合多功能材料对于可持续发展确实具有重要意义。在此，我们合成了一种新型结构良好的 S 型异质结构 Fe@TiO ₂ /硼碳氮化物 (FT/BCN)，具有高性能四环素降解和选择性 CO ₂光还原为 CH ₄。在可见光照射下, 使用性能最佳的 FT30/BCN 样品在 60 分钟内降解了 96.3% 的四环素，在 2 小时内去除了 83.2% 的总有机碳。FT30/BCN 复合催化剂的四环素降解率是裸硼碳氮化物（BCN）的 7 倍。还研究了反应参数如 pH 值、干扰电解质的存在、光源和水基质的影响。FT30/BCN 光催化剂在 CO _{2 光}还原方面表现出显着改善，如在 24.7 μmol g ^-1 h ^-1 CH ₄和 2.4 μmol g ^-1 h ^-1 CO析出中所展示的，具有最佳的 91.1% CH ₄选择性。纯 BCN 显示出较差的 39.1% 选择性。此外，碱活化的影响，CO_{还研究了 2} /H ₂ O 进料比、还原剂和光源对 CH _{4 的}产生和选择性。由于 Fe@TiO ₂和碳氮化硼之间的有效 S 型异质结引起的可见光吸收增强、高吸附电位、电荷载流子分离和光生电子的高还原能力，CH _{4 的}演化和选择性得到改善。S-方案（分步方案）电荷转移机制在四环素去除和CO ₂还原期间均起作用。还预测了抗生素去除和CO ₂还原的药物降解途径和光催化机制。